81 FR 58163 - Energy Conservation Program: Test Procedures for Central Air Conditioners and Heat Pumps
DEPARTMENT OF ENERGY
Federal Register Volume 81, Issue 164 (August 24, 2016)
Page Range
58163-58268
FR Document
2016-18993
The U.S. Department of Energy (DOE) proposes to revise its test procedures for central air conditioners and heat pumps (CAC/HP) established under the Energy Policy and Conservation Act. DOE published several proposals in a November 2015 supplemental notice of proposed rulemaking (SNOPR). DOE finalized some of the proposed test procedure amendments in a June 2016 final rule. This SNOPR proposes additional revisions to some of the amendments proposed in the past notices and proposes some additional amendments. Specifically, this SNOPR proposes two sets of amendments to the test procedure: Amendments to appendix M that would be required as the basis for making efficiency representations starting 180 days after final rule publication; and amendments as part of a new appendix M1 that would be the basis for making efficiency representations as of the compliance date for any amended energy conservation standards. Broadly speaking, the proposed amendments address the off-mode test procedures, clarifications on test set-up and fan delays, limits to gross indoor fin surface area for valid combinations, external static pressure conditions for testing, clarifications on represented values for CAC/HP that are distributed in commerce with multiple refrigerants, and the methodology for testing and calculating heating performance. DOE does not expect the proposed changes to appendix M to change measured efficiency. However, DOE has determined that the proposed procedures in new appendix M1 would change measured efficiency. DOE welcomes comments from the public on any subject within the scope of this test procedure rulemaking.
Federal Register, Volume 81 Issue 164 (Wednesday, August 24, 2016)
[Federal Register Volume 81, Number 164 (Wednesday, August 24, 2016)]
[Proposed Rules]
[Pages 58163-58268]
From the Federal Register Online [www.thefederalregister.org]
[FR Doc No: 2016-18993]
[[Page 58163]]
Vol. 81
Wednesday,
No. 164
August 24, 2016
Part III
Department of Energy
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10 CFR Parts 429 and 430
Energy Conservation Program: Test Procedures for Central Air
Conditioners and Heat Pumps; Proposed Rule
Federal Register / Vol. 81 , No. 164 / Wednesday, August 24, 2016 /
Proposed Rules
[[Page 58164]]
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DEPARTMENT OF ENERGY
10 CFR Parts 429 and 430
[Docket No. EERE-2016-BT-TP-0029]
RIN 1904-AD71
Energy Conservation Program: Test Procedures for Central Air
Conditioners and Heat Pumps
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Supplemental notice of proposed rulemaking.
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SUMMARY: The U.S. Department of Energy (DOE) proposes to revise its
test procedures for central air conditioners and heat pumps (CAC/HP)
established under the Energy Policy and Conservation Act. DOE published
several proposals in a November 2015 supplemental notice of proposed
rulemaking (SNOPR). DOE finalized some of the proposed test procedure
amendments in a June 2016 final rule. This SNOPR proposes additional
revisions to some of the amendments proposed in the past notices and
proposes some additional amendments. Specifically, this SNOPR proposes
two sets of amendments to the test procedure: Amendments to appendix M
that would be required as the basis for making efficiency
representations starting 180 days after final rule publication; and
amendments as part of a new appendix M1 that would be the basis for
making efficiency representations as of the compliance date for any
amended energy conservation standards. Broadly speaking, the proposed
amendments address the off-mode test procedures, clarifications on test
set-up and fan delays, limits to gross indoor fin surface area for
valid combinations, external static pressure conditions for testing,
clarifications on represented values for CAC/HP that are distributed in
commerce with multiple refrigerants, and the methodology for testing
and calculating heating performance. DOE does not expect the proposed
changes to appendix M to change measured efficiency. However, DOE has
determined that the proposed procedures in new appendix M1 would change
measured efficiency. DOE welcomes comments from the public on any
subject within the scope of this test procedure rulemaking.
DATES: DOE will accept comments, data, and information regarding this
supplemental notice of proposed rulemaking (SNOPR) no later than
September 23, 2016. See section V, ``Public Participation,'' for
details.
DOE will hold a public meeting on Friday, August 26, 2016, from 10
a.m. to 2 p.m., in Washington, DC. The meeting will also be broadcast
as a webinar. See section V, Public Participation, for webinar
registration information, participant instructions, and information
about the capabilities available to webinar participants.
ADDRESSES: The public meeting will be held at the U.S. Department of
Energy, Forrestal Building, Room 1E-245, 1000 Independence Avenue SW.,
Washington, DC 20585.
Any comments submitted must identify the Test Procedure SNOPR for
central air conditioners and heat pumps, and provide docket number
EERE-2016-BT-TP-0029 and/or regulatory information number (RIN) number
1904-AD 71. Comments may be submitted using any of the following
methods:
(1) Federal eRulemaking Portal: www.regulations.gov. Follow the
instructions for submitting comments.
(2) Email: [email protected]">CACHeatPump2016[email protected] Include the docket
number and/or RIN in the subject line of the message.
(3) Mail: Appliance and Equipment Standards Program, U.S.
Department of Energy, Building Technologies Office, Mailstop EE-5B,
1000 Independence Avenue SW., Washington, DC 20585-0121. If possible,
please submit all items on a CD, in which case it is not necessary to
include printed copies.
(4) Hand Delivery/Courier: Appliance and Equipment Standards
Program, U.S. Department of Energy, Building Technologies Office, 950
L'Enfant Plaza, SW., 6th Floor, Washington, DC 20024. Telephone: (202)
586-6636. If possible, please submit all items on a CD, in which case
it is not necessary to include printed copies.
For detailed instructions on submitting comments and additional
information on the rulemaking process, see section V of this document
(Public Participation).
Docket: The docket, which includes Federal Register notices,
comments, and other supporting documents/materials, is available for
review at www.regulations.gov. All documents in the docket are listed
in the www.regulations.gov index. However, some documents listed in the
index, such as those containing information that is exempt from public
disclosure, may not be publicly available.
The docket Web page can be found at https://www.regulations.gov/docket?D=EERE-2016-BT-TP-0029. The docket Web page will contain simple
instructions on how to access all documents, including public comments,
in the docket. See section V for information on how to submit comments
through www.regulations.gov.
FOR FURTHER INFORMATION CONTACT:
Ashley Armstrong, U.S. Department of Energy, Office of Energy
Efficiency and Renewable Energy, Building Technologies Program, EE-5B,
1000 Independence Avenue SW., Washington, DC 20585-0121. Telephone:
(202) 586-6590. Email: [email protected].
Johanna Jochum, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW., Washington, DC 20585-
0121. Telephone: (202) 287-6307. Email: [email protected].
For further information on how to submit a comment, review other
public comments and the docket, or participate in the public meeting,
contact the Appliance and Equipment Standards Program staff at (202)
586-6636 or by email: [email protected]">CACHeatPump2016[email protected].
SUPPLEMENTARY INFORMATION: DOE is not proposing to incorporate any new
standards by reference in this supplemental notice of proposed
rulemaking.
Table of Contents
I. Authority and Background
A. Authority
B. Background
II. Synopsis of the Supplemental Notice of Proposed Rulemaking
III. Discussion
A. Testing, Rating, and Compliance of Basic Models of Central
Air Conditioners and Heat Pumps
1. Representation Accommodation
2. Highest Sales Volume Requirement
3. Determination of Certified Rating for Multi-Split, Multi-
Circuit, and Multi-Head Mini-Split Systems
4. Service Coil Definition
5. Efficiency Representations of Split-Systems for Multiple
Refrigerants
6. Representation Limitations for Independent Coil Manufacturers
7. Reporting of Low-Capacity Lockout for Air Conditioners and
Heat Pumps With Two-Capacity Compressors
8. Represented Values of Cooling Capacity
B. Proposed Amendments to Appendix M Testing To Determine
Compliance With the Current Energy Conservation Standards
1. Measurement of Off Mode Power Consumption: Time Delay for
Units With Self-Regulating Crankcase Heaters
2. Refrigerant Pressure Measurement Instructions for Cooling and
Heating Heat Pumps
[[Page 58165]]
3. Revised EER and COP Interpolation Method for Units Equipped
With Variable Speed Compressors
4. Outdoor Air Enthalpy Method Test Requirements
5. Certification of Fan Delay for Coil-Only Units
6. Normalized Gross Indoor Fin Surface Area Requirements for
Split Systems
7. Modification to the Test Procedure for Variable-Speed Heat
Pumps
8. Clarification of the Requirements of Break-in Periods Prior
to Testing
9. Modification to the Part Load Testing Requirement of VRF
Multi-Split Systems
10. Modification to the Test Unit Installation Requirement of
Cased Coil Insulation and Sealing
C. Appendix M1 Proposal
1. Minimum External Static Pressure Requirements
2. Default Fan Power for Rating Coil-Only Units
3. Revised Heating Load Line Equation
4. Revised Heating Mode Test Procedure for Units Equipped With
Variable Speed Compressors
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Order 12866
B. Review Under the Regulatory Flexibility Act
C. Review Under the Paperwork Reduction Act of 1995
D. Review Under the National Environmental Policy Act of 1969
E. Review Under Executive Order 13132
F. Review Under Executive Order 12988
G. Review Under the Unfunded Mandates Reform Act of 1995
H. Review Under the Treasury and General Government
Appropriations Act, 1999
I. Review Under Executive Order 12630
J. Review Under Treasury and General Government Appropriations
Act, 2001
K. Review Under Executive Order 13211
L. Review Under Section 32 of the Federal Energy Administration
Act of 1974
M. Description of Materials Incorporated by Reference
V. Public Participation
A. Attendance at the Public Meeting
B. Procedure for Submitting Prepared General Statements for
Distribution
C. Conduct of the Public Meeting
D. Submission of Comments
E. Issues on Which DOE Seeks Comment
VI. Approval of the Office of the Secretary
I. Authority and Background
A. Authority
Title III, Part B \1\ of the Energy Policy and Conservation Act of
1975 (``EPCA'' or ``the Act''), Public Law 94-163 (42 U.S.C. 6291-6309,
as codified) sets forth a variety of provisions designed to improve
energy efficiency and established the Energy Conservation Program for
Consumer Products Other Than Automobiles.\2\ These products include
central air conditioners and central air conditioning heat pumps,\3\
(single-phase \4\ with rated cooling capacities less than 65,000
British thermal units per hour (Btu/h))), which are the focus of this
SNOPR. (42 U.S.C. 6291(1)-(2), (21) and 6292(a)(3))
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\1\ For editorial reasons, Part B was codified as Part A in the
U.S. Code.
\2\ All references to EPCA in this document refer to the statute
as amended through the Energy Efficiency Improvement Act of 2015,
Public Law 114-11 (Apr. 30, 2015).
\3\ This notice uses the term ``CAC/HP'' to refer specifically
to central air conditioners (which include heat pumps) as defined by
EPCA. 42 U.S.C. 6291(21.)
\4\ Where this notice uses the term ``CAC/HP'', they are in
reference specifically to central air conditioners and heat pumps as
defined by EPCA.
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Under EPCA, DOE's energy conservation program generally consists of
four parts: (1) Testing; (2) labeling; (3) Federal energy conservation
standards; and (4) certification, compliance, and enforcement. The
testing requirements consist of test procedures that manufacturers of
covered products must use as the basis of: (1) Certifying to DOE that
their products comply with applicable energy conservation standards
adopted pursuant to EPCA, and (2) making other representations about
the efficiency of those products. (42 U.S.C. 6293(c); 42 U.S.C.
6295(s)) Similarly, DOE must use these test procedures to determine
whether covered products comply with any relevant standards promulgated
under EPCA. (42 U.S.C. 6295(s))
EPCA sets forth criteria and procedures DOE must follow when
prescribing or amending test procedures for covered products. (42
U.S.C. 6293(b)(3)) EPCA provides, in relevant part, that any test
procedures prescribed or amended under this section shall be reasonably
designed to produce test results which measure the energy efficiency,
energy use, or estimated annual operating cost of a covered product
during a representative average use cycle or period of use, and shall
not be unduly burdensome to conduct. Id.
In addition, if DOE determines that a test procedure amendment is
warranted, it must publish proposed test procedures and offer the
public an opportunity to present oral and written comments on them. (42
U.S.C. 6293(b)(2)) Finally, in any rulemaking to amend a test
procedure, DOE must determine to what extent, if any, the amended test
procedure would alter the measured energy efficiency of any covered
product as determined under the existing test procedure. (42 U.S.C.
6293(e)(1))
The Energy Independence and Security Act of 2007 (EISA 2007),
Public Law 110-140, amended EPCA to require that, at least once every 7
years, DOE must review test procedures for all covered products and
either amend the test procedures (if the Secretary determines that
amended test procedures would more accurately or fully comply with the
requirements of 42 U.S.C. 6293(b)(3)) or publish a notice in the
Federal Register of any determination not to amend a test procedure.
(42 U.S.C. 6293(b)(1)(A))
DOE's existing test procedures for CAC/HP adopted pursuant to these
provisions appear under Title 10 of the Code of Federal Regulations
(CFR) part 430, subpart B, appendix M (``Uniform Test Method for
Measuring the Energy Consumption of Central Air Conditioners and Heat
Pumps''). These procedures establish the currently permitted means for
determining energy efficiency and annual energy consumption for CAC/HP.
Some of the amendments proposed in this SNOPR will alter the measured
efficiency, as represented in the regulating metrics of seasonal energy
efficiency ratio (SEER), energy efficiency ratio (EER), and heating
seasonal performance factor (HSPF). These amendments are proposed as
part of a new appendix M1. Use of the test procedure changes proposed
in this notice as part of a new appendix M1, if adopted, would become
mandatory to demonstrate compliance if the existing energy conservation
standards are revised. (42 U.S.C. 6293(e)(2)) In revising the energy
conservation standards in a separate rulemaking, DOE would create a
cross-walk from the existing standards under the current test procedure
to what the standards would be if tested using the revised test
procedure.
On December 19, 2007, the President signed the Energy Independence
and Security Act of 2007 (EISA 2007), Public Law 110-140, which
contains numerous amendments to EPCA. Section 310 of EISA 2007
established that the Department's test procedures for all covered
products must account for standby mode and off mode energy consumption.
(42 U.S.C. 6295(gg)(2)(A)) For CAC/HP, standby mode is incorporated
into the SEER and HSPF metrics, while off mode power consumption is
separately regulated. This SNOPR includes proposals relevant to the
determination of both SEER and HSPF (including standby mode) and off
mode power consumption. DOE would then use the cross-walked equivalent
of the existing standard as the baseline for its standards analysis to
prevent backsliding as required under 42 U.S.C. 6295(o)(1).
B. Background
DOE initiated a round of test procedure revisions for CAC/HP by
[[Page 58166]]
publishing a notice of proposed rulemaking in the Federal Register on
June 2, 2010 (June 2010 NOPR; 75 FR 31224). Subsequently, DOE published
several supplemental notices of proposed rulemaking (SNOPRs) on April
1, 2011 (April 2011 SNOPR; 76 FR 18105), on October 24, 2011 (October
2011 SNOPR: 76 FR 65616), and on November 9, 2015 (November 2015 SNOPR;
80 FR 69278) in response to comments received and to address additional
needs for test procedure revisions. The June 2010 NOPR and the
subsequent SNOPRs addressed a broad range of test procedure issues. On
June 8, 2016, DOE published a test procedure final rule (June 2016
final rule) that finalized test procedure amendments associated with
many but not all of these issues. 81 FR 36992.
On November 5, 2014, DOE published a request for information for
energy conservation standards (ECS) for CAC/HP (November 2014 ECS RFI).
79 FR 65603. In response, several stakeholders provided comments
suggesting that DOE amend the current test procedure. The November 2015
SNOPR addressed those test procedure-related comments, but, as
mentioned in this preamble, not all of the related issues were resolved
in the June 2016 final rule.
On July 14, 2015, DOE published a notice of intent to form a
Working Group to negotiate a NOPR for energy conservation standards for
CAC/HP and requested nominations from parties interested in serving as
members of the Working Group. 80 FR 40938. The Working Group, which
ultimately consisted of 15 members in addition to one member from
Appliance Standards and Rulemaking Federal Advisory Committee (ASRAC),
and one DOE representative, identified a number of issues related to
testing and certification and made several recommendations that are
being addressed in the proposals of this SNOPR. DOE believes proposed
changes are consistent with the intent of the Working Group.
This SNOPR addresses proposals and comments from two rulemakings:
(1) Stakeholder comments and proposals regarding the CAC test procedure
(CAC TP: Docket No. EERE-2009-BT-TP-0004); and (2) stakeholder comments
and proposals regarding the CAC energy conservation standard from the
Working Group (CAC ECS: Docket No. EERE-2014-BT-STD-0048). Comments
received through documents located in the test procedure docket are
identified by ``CAC TP'' preceding the comment citation. Comments
received through documents located in the energy conservation standard
docket (EERE-2014-BT-STD-0048) are identified by ``CAC ECS'' preceding
the comment citation. Further, comments specifically received during
the CAC/HP ECS Working Group meetings are identified by ``CAC ECS:
ASRAC Public Meeting'' preceding the comment citation.
II. Synopsis of the Supplemental Notice of Proposed Rulemaking
In this SNOPR, DOE proposes revising the certification requirements
and test procedure for CAC/HP based on public comment on various
published materials and the ASRAC negotiation process discussed in
section I.B. In this SNOPR, DOE proposes two sets of changes: One set
of proposed changes to Appendix M effective 30 days after publication
of a final rule and required for testing and determining compliance
with current energy conservation standards; and another set of proposed
changes to create a new Appendix M1 that would be used for testing to
demonstrate compliance with any amended energy conservation standards
(agreed to be January 1, 2023 by the Working Group in the CAC
rulemaking negotiations (CAC ECS: ASRAC Term Sheet, No. 76)). DOE
requests comment on whether representations in accordance with Appendix
M1 should be permitted prior to the compliance date of any amended
energy conservation standards. DOE does not expect the proposed changes
to Appendix M to change measured efficiency. However, DOE has
determined that the proposed procedures in the new Appendix M1 would
change measured efficiency.
In this SNOPR, DOE proposes the following changes to certification
requirements:
(1) Certification of the indoor fan off delay used for coil-only
tests.
(2) Codifying the CAC/HP ECS Working Group's recommendation
regarding delayed implementation of testing to demonstrate compliance
with amended energy conservation standards;
(3) Relaxing the requirement that a split system's tested
combination be a high sales volume combination;
(4) Revising requirements for certification of multi-split systems
in light of the proposed adoption of multiple categories of duct
pressure drop that the indoor units can provide;
(5) Making explicit certain provisions of the service coil
definition;
(6) Certification of separate individual combinations within the
same basic model for each refrigerant that can be used in a model of
split system outdoor unit without voiding the warranty; and
(7) Certification of details regarding the indoor units with which
unmatched outdoor units are tested.
DOE proposes the following changes to Appendix M:
(1) Establishment of a 4-hour or 8-hour delay time before the power
measurement for units that require the outdoor temperature setting to
reach thermal equilibrium;
(2) A limit on the internal volume of lines and devices connected
to measure pressure at refrigerant circuit locations where the
refrigerant state can switch from liquid to vapor for different test
operating conditions;
(3) Requiring bin-by-bin EER and coefficient of performance (COP)
interpolations for all variable speed units, to calculate performance
at intermediate compressor speeds;
(4) Requiring a 30-minute test without the outside-air apparatus
connected (a ``non-ducted'' test) to be the official test as part of
all cooling and heating mode tests which use the outdoor air enthalpy
method as the secondary measurement; and
(5) Imposing indoor coil size limits for split system ratings.
DOE proposes the following provisions for new Appendix M1:
(1) New higher external static pressure requirements for all units,
including unique minimum external static pressure requirements for
mobile home systems, ceiling-mount and wall-mount systems, low and mid-
static multi-split systems, space-constrained systems, and small-duct,
high-velocity systems;
(2) A unique default fan power for rating mobile home coil-only
units and new default fan power for all other coil-only units;
(3) Revisions to the heating load line equation in the calculation
of HSPF; and
(4) Amendments to the test procedures for variable speed heat pumps
that change speed at lower ambient temperatures and a 5 [deg]F heating
mode test option for calculating full-speed performance below 17
[deg]F.
If adopted, the test procedures proposed in this SNOPR to appendix
M for subpart B to 10 CFR part 430 pertaining to the efficiency of CAC/
HP would be effective 30 days after publication in the Federal Register
(referred to as the ``effective date''). Pursuant to EPCA,
manufacturers of covered products would be required to use the
applicable test procedure as the basis for determining that their
products comply with the applicable energy conservation standards. 42
U.S.C. 6295(s)) On or after 180 days after publication of a final rule,
any representations made with respect to the
[[Page 58167]]
energy use or efficiency of CAC/HPs would be required to be made in
accordance with the results of testing pursuant to the amended test
procedures. (42 U.S.C. 6293(c)(2))(42 U.S.C. 6293(c)(2))
If adopted, the test procedures proposed in this SNOPR for appendix
M1 to subpart B of 10 CFR part 430 pertaining to the efficiency of CAC/
HP would be effective 30 days after publication in the Federal
Register. The appendix M1 procedures would be required to be used as
the basis for determining that CAC/HP comply with any amended energy
conservation standards (if adopted in the concurrent CAC/HP energy
conservation standards rulemaking) and for representing efficiency as
of the compliance date for those amended energy conservation standards.
As noted in section I.A, 42 U.S.C. 6293(e) requires DOE to
determine to what extent, if any, the proposed test procedure would
alter the measured energy efficiency and measured energy use. DOE has
determined that some of the proposed amendments in the new Appendix M1
would result in a change in measured energy efficiency and measured
energy use for CAC/HP. DOE is conducting a separate rulemaking to amend
the energy conservation standards for CAC/HP, which will take into
account the test procedure revisions in Appendix M1. (CAC ECS: Docket
No. EERE-2014-BT-STD-0048)
III. Discussion
This section discusses the revisions to the certification
requirements and test procedure that DOE proposes in this SNOPR.
A. Testing, Rating, and Compliance of Basic Models of Central Air
Conditioners and Heat Pumps
1. Representation Accommodation
The CAC/HP ECS Working Group made certain recommendations related
to the Appendix M1 test procedure, with a recommended compliance date
of January 1, 2023, for representations based on Appendix M1. (Docket
No. EERE-2014-BT-STD-0048, No. 76, Recommendation #7) While the June
2016 Test Procedure Final Rule adopted mandatory testing requirements
for representations of all basic models [81 FR at 37050-37051; 10 CFR
429.16(b)(2)(i)], the Working Group recommended several accommodations
for representations for split systems:
[cir] DOE will implement the following accommodation for
representative values of split system air conditioners and heat pumps
based on the M1 methodology:
[cir] By January 1, 2023, manufacturers of single-split systems
must validate an AEDM that is representative of the amended M1 test
procedure by:
[ssquf] Testing a single-unit sample for 20-percent of the basic
models certified.
[ssquf] The predicted performance as simulated by the AEDM must be
within 5 percent of the performance resulting from the test of each of
the models.
[ssquf] Although DOE will not require that a full complement of
testing be completed by January 1, 2023, manufacturers are responsible
for ensuring their representations are appropriate and that the models
being distributed in commerce meet the applicable standards (without a
5% tolerance).
[cir] By January 1, 2023, manufacturers must either determine
representative values for each combination of single-split-system CAC/
HP based on the M1 test procedures using a validated AEDM or through
testing and the applicable sampling plan.
[cir] By January 1, 2023, manufacturers of multi-split, multi-
circuit, or multi-head mini-split systems must determine representative
values for each basic model through testing and the applicable sampling
plan.
[cir] By July 1, 2024, each model of condensing unit of split
system CAC/HP must have at least 1 combination whose rating is based on
testing using the M1 test procedure and the applicable sampling plan.
(Docket No. EERE-2014-BT-STD-0048, No. 76, Recommendation #10)
DOE proposes to implement these recommendations, in their entirety,
in 10 CFR 429.16 and 429.70.
2. Highest Sales Volume Requirement
The CAC/HP ECS Working Group recommended that DOE implement the
following requirements for single-split-system air conditioners and
suggested implementing regulatory text:
Every combination distributed in commerce must be rated.
[cir] Every single-stage and two-stage condensing unit distributed
in commerce (other than a condensing unit for a 1-to-1 mini split) must
have at least 1 coil-only rating that is representative of the least
efficient coil distributed in commerce with a particular condensing
unit.
Every condensing unit distributed in commerce must have at
least 1 tested combination.
[cir] For single-stage and two-stage condensing units (other than
condensing units for a 1-to-1 mini split), this must be a coil-only
combination.
All other combinations distributed in commerce for a given
condensing unit may be rated based on the application of an AEDM or
testing in accordance with the applicable sampling plan.
(Docket No. EERE-2014-BT-STD-0048, No. 76, Recommendation #7)
DOE addressed the first and third bullets in a final rule published
on June 8, 2016, (June 2016 final rule), but at that time declined to
implement the second bullet, which recommends removing the requirement
that the tested combination be the highest sales volume combination
(HSVC). DOE also received comments from non-working group members
regarding this requirement. JCI commented that the current language
used in Appendix M denoting the HSVC match cannot be determined with
exact statistics and that it actually inhibits the adoption of new and
promising advancements in product design. (CAC TP: JCI, No. 66 at p. 4)
In contrast, Unico commented that, as an indoor coil manufacturer, it
believes it to be important that the outdoor unit manufacturer continue
to test and rate the HSVC, as this is an integral requirement for their
AEDM to maintain accuracy. (CAC TP: Unico, No. 63 at p. 2)
DOE believes the CAC/HP ECS Working Group recommendation adequately
addresses JCI's concern about using the HSVC as a tested combination.
In response to Unico, DOE notes that the requirements adopted in the
June 2016 final rule require independent coil manufacturers (ICMs) to
test their own equipment. It is the ICM's own responsibility to ensure
the accuracy of its AEDMs. ICMs may conduct additional testing or work
with outdoor unit manufacturers (OUMs) as needed to do so. For these
reasons, DOE is proposing to remove the requirement that the tested
combination be the HSVC. DOE proposes to apply the requirements as
recommended by the CAC/HP ECS Working Group to all single-split-system
air conditioners and heat pumps, including space-constrained and small-
duct, high-velocity, distributed in commerce by an OUM.
3. Determination of Certified Rating for Multi-Split, Multi-Circuit,
and Multi-Head Mini-Split Systems
In the June 2016 final rule, DOE modified the testing requirements
for multi-head mini-split systems and multi-split systems, and added
similar requirements for testing multi-circuit systems. DOE also
clarified that these requirements apply to variable refrigerant flow
(VRF) systems that are
[[Page 58168]]
single-phase and less than 65,000 Btu/h.\5\ For all multi-split, multi-
circuit, and multi-head mini-split systems, DOE required that, at a
minimum, each model of outdoor unit must be tested as part of a tested
combination (as defined at 10 CFR 430.2) that includes only non-ducted
indoor units. For any models of outdoor units also sold with ducted
indoor units, a second ``tested combination'' including only ducted
indoor units must be tested. DOE also allowed for manufacturers to rate
a mixed non-ducted/ducted combination as the mean of the represented
values for the tested non-ducted and ducted combinations, and allowed
manufacturers to test and rate specific individual combinations as
separate basic models, even if they share the same model of outdoor
unit. 81 FR 37003-37005 (June 8, 2016)
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\5\ A VRF system is a multi-split system with at least three
compressor capacity stages, but most VRF systems have variable-speed
compressors.
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DOE also added a requirement that for any models of outdoor units
also sold with models of small-duct, high velocity (SDHV) indoor units,
a ``tested combination'' composed entirely of SDHV indoor units must be
used for testing and rating. However, such a system must be certified
as a different basic model. Finally, DOE allowed mix-match ratings for
SDHV and other non-ducted or ducted indoor units based on an average of
the ratings of the two individual indoor unit types. 81 FR 37004 (June
8, 2016)
In the June 2010 NOPR, DOE had proposed lower minimum external
static pressure (ESP) requirements for ducted multi-split systems (75
FR at 31232), and in the November 2015 SNOPR, DOE proposed to implement
these requirements using the term ``short duct systems,'' which could
refer to multi-split, multi-head mini-split, or multi-circuit systems
with indoor units that produce a limited level of external static
pressure. 80 FR at 69314 (Nov. 9, 2015). In response to the SNOPR, DOE
received several comments regarding its terminology and testing
requirements related to short-duct systems as well as requests for
changing terminology and testing requirements to include low-static and
mid-static systems, as recommended in the CAC/HP ECS Working Group Term
Sheet. Therefore in the June 2016 final rule, DOE maintained the
existing ducted system terminology and is addressing the earlier
comments from stakeholders and recommendations from the Working Group
in this SNOPR.
Unico supported DOE's definition of short-ducted systems which
would create four indoor unit types for multi-split systems: Short-
ducted (previously described as ``ducted''), conventional ducted, SDHV-
ducted, and non-ducted. (CAC TP: Unico, No. 63 at p. 11) In the Term
Sheet, the CAC/HP ECS Working Group recommended that DOE define ``low-
static system'' and ``mid-static system'' as discussed in section
III.C.1. (CAC ECS: Docket No. EERE-2014-BT-STD-0048, No. 76 at p. 1-2)
These systems are essentially sub-categories of DOE's earlier proposal
for short-ducted systems.
In addition, several stakeholders commented that multi-split
systems may also be paired with models of conventional ducted indoor
units. UTC/Carrier commented that some manufacturers also offer ducted
units with external static pressure capabilities greater than 0.65 in
w.c., the maximum external static pressure proposed by the Working
Group for mid-static ducted units and recommended that DOE also include
a requirement for separate multi-split system ratings with these
``standard'' ducted indoor units. (CAC TP: UTC/Carrier, No. 62 at p. 3-
4)
Rheem commented that the definition of multi-split system is not
limited to a specific duct configuration and that testing of all
possible duct configurations should be considered. Rheem further
commented that the testing requirements should be the same as single-
split systems using conventional ducted indoor units because multi-
split systems duct losses are the same as the standard single-split
system. (CAC TP: Rheem, No. 69 at p. 5)
NEEA and NPCC commented that multi-split systems paired with more
conventional blower coil indoor units should be testable with the
external static pressure conditions specified for conventional blower
coil units. (CAC TP: NEEA and NPCC, No. 64 at p. 3-4)
The California IOUs commented that additional testing is needed to
ensure that the AEDM gives accurate ratings for all of the possible
combinations when an outdoor unit of a multi-split system is paired
with a conventional central forced air indoor unit. They said that, at
present, a variable speed, mini-split outdoor unit is connected to an
indoor unit(s) from the same manufacturer with complex software
controls that produce the variable modes of operation needed to respond
to indoor and outdoor conditions. They also asserted that the indoor
units can be short ducted or ductless cassettes. Finally, they
commented that, if the same outdoor section is installed with a central
forced air unit, it will have indoor fan operation modes and
significantly different power draw and may not be representative of the
nuanced behavior of the ductless and short duct components. (CAC TP:
California IOUs, No. 67 at p. 3)
Given the multiple types of indoor units with which these systems
can be paired, several stakeholders also made recommendations related
to the testing and rating requirements.
Unico commented that multi-split ratings should be listed with
homogeneous type of indoor units, which should be based on tests or a
valid AEDM. Unico commented that short-ducted, conventional-ducted,
SDHV-ducted and non-ducted are different types and should all be tested
and rated using the appropriate test procedure for the type, and that
ratings with mixed types should be an average. (CAC TP: Unico, No. 63
at p. 2)
Mitsubishi proposed that given the potential additional testing
requirements presented for systems with multiple families of ducted
indoor unit (low-static, mid-static and standard-static ducted), a
manufacturer be allowed to produce tested combinations of all low-
static, all mid-static or all standard-static indoor units, and that,
if they do not wish to have separate ratings, they must use the highest
rating of external static pressure to establish the tested combination.
(CAC TP: Mitsubishi, No. 68 at p. 3)
Goodman suggested that any combinations of non[hyphen]ducted, low-
static, mid-static and/or high-static indoor units be based on the
highest static units in the combination if a single rating is to be
used for all short[hyphen]ducted indoor units. In addition, Goodman
stated that it believes these combinations should have the capability
of being rated and certified using either test data or an AEDM. Goodman
suggested that, if multiple combinations of non-ducted, low-static,
mid-static and/or high-static indoor units are matched with a
particular outdoor unit, the testing should be performed using the
appropriate test static for each indoor unit. (CAC TP: Goodman, No. 73
at p. 13-14)
DOE supports the Working Group recommendations to replace its
proposal to use the terminology short-duct with low-static and mid-
static. The proposed definitions for these terms are discussed in
section III.C.1. In addition, DOE agrees that multi-split, multi-head
mini-split, or multi-circuit systems can include conventional ducted
indoor units. DOE notes that the proposed test procedure allows
selection of an appropriate external static pressure for this case.
[[Page 58169]]
After reviewing the comments, DOE proposes that multi-split, multi-
head mini-split, and multi-circuit systems can be tested and rated with
five kinds of indoor units: Non-ducted, low-static ducted, mid-static
ducted, conventional ducted, or SDHV. However, DOE agrees that if a
manufacturer offers an outdoor model with all five kinds of indoor
units, a requirement to determine a rating through testing of each
could be burdensome. Therefore, DOE proposes that, when determining
represented values including certifying compliance with amended energy
conservation standards, at a minimum, a manufacturer must test and rate
a ``tested combination'' composed entirely of non-ducted units. If a
manufacturer also offers the model of outdoor unit with models of low-
static, mid-static, and/or conventional ducted indoor units, the
manufacturer must at a minimum also test and rate a second ``tested
combination'' with the highest static variety of indoor unit offered.
The manufacturer may also choose to test and rate additional ``tested
combinations'' composed of the lower static varieties. In each case,
the manufacturer must test with the appropriate external static
pressure. DOE believes that this option reduces test burden
sufficiently and is not proposing use of AEDMs for these systems.
DOE proposes to maintain its requirement from the June 2016 final
rule that, if a manufacturer also sells a model of outdoor unit with
SDHV indoor units, the manufacturer must test and rate the SDHV system
(i.e. test a combination with indoor units that all have SDHV pressure
capability). DOE also proposes to continue to allow mix-match ratings
across any two of the five varieties by taking a straight average of
the ratings of the individual varieties, and to allow ratings of
individual combinations through testing. As noted in the June 2016
final rule, SDHV represented values must be a separate basic model. Any
represented values for a mixed system including SDHV and another style
of unit must be in the same basic model as the SDHV model. Tables III.1
and III.2 summarize example represented values.
[GRAPHIC] [TIFF OMITTED] TP24AU16.000
Table III.2--Example Represented Values for SDHV Multi-Split Systems
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Individual Individual
Basic model model No. model No.(s) Sample size SDHV rep. Mix rep. Mix rep. Mix rep. Mix rep.
(outdoor unit) (indoor unit) value value (ND) value (CD) value (MS) value (LS)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ABC-SDHV........................................................ ABC * * * 6 11.50 13.25 12.75 .............. ..............
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
4. Service Coil Definition
In the June 2016 final rule, to distinguish newly installed cased
and uncased coils from replacement cased and uncased coils, DOE added a
definition for service coils and explicitly excluded them from indoor
units in the indoor unit definition:
Indoor unit means part of a split-system air conditioner or heat
pump that includes (a) an arrangement of refrigerant-to-air heat
transfer coil(s) for transfer of heat between the refrigerant and
the indoor air and (b) a condensate drain pan, and may or may not
include (c) sheet metal or plastic parts not part of external
cabinetry to direct/route airflow over the coil(s), (d) a cooling
mode expansion device, (e) external cabinetry, and (f) an integrated
indoor blower (i.e. a device to move air including its associated
motor). A separate designated air mover that may be a furnace or a
modular blower (as defined in Appendix AA to the subpart) may be
considered to be part of the indoor unit. A service coil is not an
indoor unit.
Service coil means an arrangement of refrigerant-to-air heat
transfer coil(s) and condensate drain pan that may or may not
include sheet metal or plastic parts to direct/route airflow over
the coil(s), external cabinetry, and/or a cooling mode expansion
device, and is sold exclusively to replace an uncased coil or cased
coil that has already been placed into service and is labeled
accordingly.
In this SNOPR, DOE proposes to modify the adopted definition of
service coil to more explicitly define what ``labeled accordingly''
means. Under 42 U.S.C. 6295(r), the Secretary may include any
requirement which the Secretary determines is necessary to assure that
each covered product to which such standard applies meets the required
minimum level of energy efficiency or maximum quantity of energy use
specified in such standard.
[[Page 58170]]
In this specific case, DOE believes service coils must be distinguished
from indoor units to ensure compliance with the applicable energy
conservation standards for central air conditioners and heat pumps.
Specifically, DOE proposes that a manufacturer must designate a service
coil as ``for indoor coil replacement only'' on the nameplate and in
manufacturer product and technical literature. In addition, the model
number for any service coil must include some mechanism (e.g., an
additional letter or number) for differentiating a service coil from a
coil intended for an indoor unit.
5. Efficiency Representations of Split-Systems for Multiple
Refrigerants
Split-system CAC/HP are required to be tested as a system. Prior to
the June 2016 final rule, the condensing unit was required to be tested
with ``the evaporator coil that is likely to have the largest volume of
retail sales with the particular model of condensing unit'' (commonly
referred to as the highest sales volume combination or HSVC). 10 CFR
429.16(a)(2)(ii) as of January 1, 2016. The June 2016 final rule
amended the definition of ``central air conditioner or central air
conditioning heat pump'' to recognize instances in which there is no
HSVC, i.e., an outdoor unit is sold separately with no matching indoor
unit, referred to as an ``outdoor unit with no match''. 81 FR at 36999
(June 8, 2016).
As discussed in the June 2016 final rule, outdoor units with no
match are typically a result of the phase-out of HCFC-22 refrigerant.
Effective January 1, 2010, the U.S. Environmental Protection Agency
(EPA) banned the sale and distribution of those central air
conditioning systems and heat pump systems that are designed to use
HCFC-22 refrigerant. 74 FR 66450 (Dec. 15, 2009). EPA's rulemaking
included an exception for the manufacture and importation of
replacement components, as long as those components are not pre-charged
with HCFC-22. Id. at 66459-60. Because complete HCFC-22 systems can no
longer be distributed, DOE established test procedure requirements for
outdoor units that have ``no match,'' or are not sold with a matching
indoor unit, which includes those units designed to use HCFC-22.
The ``no match'' test procedure's goal is that the test should
produce measurements of energy efficiency during a representative
average use cycle (see 42 U.S.C. 6293(b)(3)) while also ensuring that
any field-matched combination (including the new ``no-match'' outdoor
unit and an existing indoor unit) meets the standard. Due to the nature
of these no-match systems, however, neither the manufacturer nor DOE
knows exactly what the paired system will be for an outdoor unit with
no match. To ensure compliance, DOE established indoor unit
specifications that are representative of a less efficient unit
(representative of units on the market at the time of the change in EPA
regulations) that could be paired with the given outdoor unit with no
match. Specifically, DOE established a requirement that outdoor units
without a matching indoor unit must be tested with an indoor unit with
a normalized gross indoor fin surface (NGIFS) \6\ no higher than 1.0
square inches per British thermal unit per hour (sq. in./Btu/hr). 81 FR
at 37010 (June 8, 2016).
---------------------------------------------------------------------------
\6\ NGIFS is equal to normalized gross indoor fin surface (for a
conventional fin-tube heat exchanger, two times fin length times fin
width times the number of fins) divided by the system cooling
capacity.
---------------------------------------------------------------------------
In response to the phase-out of HCFC-22, one course pursued by
manufacturers has been to use the refrigerant R-407C, which can be used
as a drop-in replacement for HCFC-22 if oil compatibility issues are
addressed. (No. 1 at pp. 2-6) Because R-407C is a replacement for HCFC-
22, it is possible for a central air conditioner to operate either with
R-407C or with HCFC-22. Such a unit could be shipped charged with R-
407C, or shipped without the refrigerant charge (i.e., dry-shipped). A
dry-shipped unit could then either be sold as part of an R-407C split-
system, or sold as a replacement component and charged with HCFC-22. In
any case, R-407C outdoor units are often marketed as replacements for
HCFC-22 outdoor units, as indicated in marketing material. (Docket No.
EERE-2016-BT-TP-0029-0007, -0008, -0009, -0010, -0011, -0012 and -0013)
Some R-407C outdoor units are more explicitly marketed as HCFC-22
replacements than other units (e.g., indicating that the outdoor unit
is ``compatible with R-22 coils and linesets!''). ((Docket No. EERE-
2016-BT-TP-0029-0010 at p. 1).
To address instances in which the manufacturer indicates that more
than one refrigerant is acceptable for use in a unit (i.e., the
manufacturer specifications include use of multiple refrigerants or the
warranty would not be voided by the use of more than one refrigerant),
DOE is proposing that a split-system air conditioner or heat pump,
including outdoor unit with no match, must be certified as a separate
individual combination (including outdoor unit without match as
applicable) for every acceptable refrigerant. Specifically, each
individual combination (including outdoor unit without match
corresponding to each acceptable refrigerant) would be certified under
the same basic model. DOE's existing requirements for basic models
would continue to apply; therefore, if an individual combination or an
outdoor unit with no match fails to meet DOE's energy conservation
standards using any refrigerant indicated by the manufacturer to be
acceptable, then the entire basic model would fail. DOE also proposes
that manufacturers must certify the refrigerant for every individual
combination that is distributed in commerce (including every outdoor
unit with no match). For models where the manufacturer only indicates
one acceptable refrigerant (DOE expects this to be the majority of
units), this proposal would simply entail certifying to DOE the
refrigerant for which the model is designed. Finally, DOE proposes that
if a model of outdoor unit (used in a single-split, multi-split, multi-
circuit, multi-head mini-split, and/or outdoor unit with no match
system) is distributed in commerce without a specific refrigerant
specified or not charged with a specified refrigerant from the point of
manufacture, a manufacturer must determine the represented value as an
outdoor unit with no match.
Under this proposal, if an outdoor unit manufacturer (OUM)
indicates as an acceptable refrigerant for a model of outdoor unit a
refrigerant that is banned for inclusion in CAC/HP distributed as
systems, such as HCFC-22, the OUM would have to determine represented
values (e.g., SEER) for the model of outdoor unit tested as an outdoor
unit with no match. Within the same basic model, the manufacturer must
determine a represented value for all individual split-system
combinations using the same model of outdoor unit for any acceptable
refrigerants with which the model of outdoor unit can legally be sold
as a system. DOE has tentatively determined that specification by an
OUM as to the acceptable refrigerant indicates the ultimate use or uses
for which the unit was designed and manufactured.
Inclusion of HCFC-22 as an acceptable refrigerant by the
manufacturer indicates that the model of outdoor unit was designed and
manufactured to be sold separately as a replacement component (i.e., as
a model of outdoor unit with no match), because manufacturers are
prohibited from selling and distributing central air conditioning
systems and heat pump systems that use HCFC-22 refrigerant,
[[Page 58171]]
except as replacement components (i.e., outdoor units with no match).
As indicated previously in this discussion, it is DOE's
understanding that the listing of acceptable refrigerants also impacts
the unit's warranty. In order for a unit to remain under warranty, the
unit generally must be operated and maintained as recommended by the
manufacturer. If a manufacturer indicates that HCFC-22 is an acceptable
refrigerant, its use in an outdoor unit would not be expected to void
the warranty. Again, DOE understands conformance with the warranty to
be an indication of the intended use for which a model is designed and
manufactured. Additionally, DOE understands that manufacturer
literature for some models may not explicitly state which refrigerants
may be used without voiding the warranty and may instead generally
refer to specific refrigerant characteristics for the warranty to
remain valid. If for such a case, HCFC-22 meets the specified
characteristics, DOE's proposal would require that the manufacturer
certify, within the same basic model, an individual split-system
combination or outdoor unit with no match for each refrigerant that
meet these warranty criteria or characteristics.
Under the certification requirements proposed in this SNOPR, an
outdoor unit for which both R-407C and HCFC-22 are acceptable
refrigerants would need to be certified as a split-system combination
and as an outdoor unit with no match, with representations for each.
Per DOE's regulations established in the June 2016 final rule, outdoor
units with no match cannot be certified using an AEDM, and the model of
outdoor unit must be tested with an indoor unit meeting specified
criteria. 81 FR at 37051 (June 8, 2016). Therefore, for a model of
outdoor unit for which both R-407C and HCFC-22 are acceptable
refrigerants, the outdoor unit with no match (with HCFC-22) must be
tested and certified. In addition, DOE proposes to require that any
split-system combination (with R-407C) must also be tested. The
proposed certification requirements would represent the energy
efficiency of an outdoor unit during a representative average use cycle
for each intended sales scenario (i.e., either sold as a split system
and installed with a new matching indoor unit, or sold as a replacement
component and installed with a legacy indoor unit).
In addition, DOE recognizes that concerns regarding warrantee
coverage for a given refrigerant may not be a concern for all
installers and consumers. Consequently, DOE is concerned that the lack
of explicit indication that a unit is acceptable for use with HCFC-22
may not prevent installation of such units with the refrigerants, if
the installers and consumers have reasonable confidence that the unit
can operate with this refrigerant. Because of the similarity of HCFC-22
and R-407C and the history of CAC/HP being used interchangeably with
both of these refrigerants, this issue could very well arise for any
unit certified and warranted for use with R-407C. Hence, DOE proposes
that any outdoor unit intended for use in a split system with R-407C,
i.e. any unit shipped with a charge of any amount of R-407C, would also
have to be rated as an outdoor unit with no match.
Nearly all outdoor units of split systems are shipped with a
quantity of refrigerant charge that is close to the required charge for
installation. This has been confirmed by observation of units tested by
DOE. Line sets for connecting indoor units to outdoor units also are
sold with an appropriate pre-charge to compensate for the different
amount of charge that remains in the lines of different-length line
sets. During set-up, the refrigerant charge of the assembled system is
adjusted, and the pre-charging of the components limits the amount of
refrigerant that is needed to be added or removed in order to match the
charging conditions specified in the manufacturer's installation
instructions. Because of this general practice to ship outdoor units
with close to full charge, DOE considers use of a charge quantity that
is much less than the charge specified by the instructions to be
equivalent to shipping a unit without refrigerant. Hence, DOE proposes
to require a no-match rating for outdoor units that are shipped with a
charge amount such that adjustment of charge as specified in
manufacturer's instructions requires addition of more than one pound of
refrigerant.
As an example illustrating the certification requirement proposals
discussed in this section, assume a manufacturer advertises a model of
outdoor unit for use with either HCFC-22 or R-407C.
In 10 CFR 430.2 (as amended in the June 2016 final rule), DOE
defines ``basic model'' for OUMs as ``all individual combinations
having the same model of outdoor unit, which means comparably
performing compressor(s) [a variation of no more than five percent in
displacement rate (volume per time) as rated by the compressor
manufacturer, and no more than five percent in capacity and power input
for the same operating conditions as rated by the compressor
manufacturer], outdoor coil(s) [no more than five percent variation in
face area and total fin surface area; same fin material; same tube
material], and outdoor fan(s) [no more than ten percent variation in
air flow and no more than twenty percent variation in power input].''
According to this definition, the model of outdoor unit intended to be
sold with both HCFC-22 and R-407C would represent multiple individual
combinations within the same basic model. Therefore, a manufacturer has
to determine a represented value for each single-split-system
combination (sold for use with R-407C) as well as determine a
represented value for the outdoor unit with no match (sold for use with
HCFC-22). See 10 CFR 429.16(a)(1) (as amended in the June 2016 final
rule), 81 FR 36001, 37056 (June 8, 2016).
Paragraph 10 CFR 429.16(b)(2)(i) (as amended in the June 2016 final
rule) details the minimum testing requirements for each basic model,
specified by equipment category. In this SNOPR, DOE is proposing to
further specify in that same paragraph that when a basic model spans
listed categories, as in this example, multiple testing requirements
apply. Therefore, the manufacturer would have to test at least one
single-split-system combination as well as the model of outdoor unit
with a model of coil-only indoor unit meeting the requirements of
section 2.2e of Appendix M or M1 to subpart B of part 430 (i.e., test
as an outdoor unit with no match). Under 10 CFR 429.16(c)(1)(i) (as
amended in the June 2016 final rule), any other single-split
combinations within the basic model may be tested or rated using an
AEDM according to the applicable requirements. 81 FR 36001, 37049 (June
8, 2016).
In the event that DOE determines a basic model is noncompliant with
an applicable energy conservation standard, DOE may issue a notice of
noncompliance determination that, among other things, informs the
manufacturer of its obligation to cease distribution of the basic model
immediately. (10 CFR 429.114(a)) Therefore, if any individual
combination (including the outdoor unit with no match) fails to comply
with the applicable standard, whether the combination has been tested
or rated using an AEDM, the entire basic model must be removed from the
market and the model of outdoor unit may not be sold at all.
DOE also notes that although the discussion in this section of the
SNOPR is directly related to refrigerants, a basic model may span
listed categories in
[[Page 58172]]
other situations. For example, as mentioned in the June 2016 final
rule, a model of outdoor unit may be sold both as part of a single-
split system and as part of a multi-split system. 81 FR at 37005. In
this case, the manufacturer would have to determine represented values
within each of these categories as required by 429.16(a)(1) and would
have to meet the testing requirements for each category in
429.16(b)(2)(i). Furthermore, if an individual combination that is
either a single-split or multi-split system fails to comply with the
standard, the model of outdoor unit may not be sold for use in either
category.
DOE also proposes to add information to the items required to be
provided in certification reports to address outdoor units with no
match. The general certification requirements for air conditioners and
heat pumps as amended in the June 2016 final rule already apply to
outdoor units with no match. These requirements include reporting of
SEER, the average off mode power consumption, the cooling capacity, the
region(s) in which the basic model can be sold, HSPF (for heat pumps),
and EER (for air conditioners), and non-public information including
indoor air volume rate for the relevant operating modes (e.g., full-
load cooling, part-load cooling, full-load heating). 81 FR 36991, 37053
(June 8, 2016). In this SNOPR, DOE proposes to require reporting of
additional non-public information for the indoor unit that is tested
with an outdoor unit with no match. This would include the indoor coil
face area, depth in the direction of airflow, fin density (fins per
inch), fin material, fin style (e.g., wavy or louvered), tube diameter,
tube material, and numbers of tubes high and deep. These additional
requirements would apply to outdoor units with no match, whether or not
the outdoor unit was also certified as part of an individual
combination.
Issue 1: DOE requests comment on its proposed certification
requirements for outdoor units with no match. Also, DOE seeks comment
on what fin style options should be considered as options for CCMS
database data entry.
6. Representation Limitations for Independent Coil Manufacturers
In the June 2016 final rule, DOE discussed compliance with Federal
(base national or regional) standards for CAC/HP. Specifically DOE
cited a proposal in the November 2015 SNOPR to amend 10 CFR 430.32 to
clarify that the least-efficient combination within each basic model
must comply with the regional SEER and EER standards. 80 FR 69277,
69290 (Nov. 9, 2015). However, DOE declined to modify section 430.32 in
the June 2016 final rule, instead stating that it would do so in the
regional standards enforcement rulemaking. 81 FR 36991, 37012 (June 8,
2016). Instead, DOE adopted language in 10 CFR 429.16 specifying that a
basic model may only be certified as compliant with a regional standard
if all individual combinations within that basic model meet the
regional standard for which that basic model would be certified and
that an ICM cannot certify a basic model containing a representative
value that is more efficient than any combination certified by an OUM
containing the same outdoor unit. 81 FR at 37050.
In response to the June 2016 final rule, Advanced Distributor
Products (ADP) and Lennox International submitted separate but
essentially identical letters and AHRI submitted a similar letter
(Docket No. EERE-2016-BT-TP-0029-0006, -0005, and -0003) stating that
this language, while intended to define that ICM ratings cannot provide
a means for an outdoor unit to span regions, is inconsistent with the
Regional Standards ASRAC Working Group agreement (Docket No. EERE-2011-
BT-CE-0077-0070). ADP, Lennox, and AHRI suggested that language
proposed in the regional standards enforcement NOPR (80 FR 72389-
72390), but not finalized, captured the enforcement working group
intent and avoids inadvertent limitations on independent coil
manufacturers. Mortex also submitted a letter (Docket No. EERE-2016-BT-
TP-0029-0004) commenting on the same language, also stating that it
seems inconsistent with agreements made during the Regional Standards
ASRAC Working Group. Mortex suggested that the requirement be removed
from the test procedure.
DOE did not adopt the language proposed in the regional standards
enforcement NOPR in response to comments submitted in that rulemaking.
DOE agrees, however, that the language adopted at 429.16 inadvertently
constrains ICMs beyond the bounds agreed to in the Regional Standards
ASRAC Working Group. Accordingly, DOE proposes to remove the sentence:
``An ICM cannot certify a basic model containing a representative value
that is more efficient than any combination certified by an OUM
containing the same outdoor unit.'' and replace it with the following
language in 429.16(a)(4)(i): An ICM cannot certify an individual
combination with a rating that is compliant with a regional standard if
the individual combination includes a model of outdoor unit that the
OUM has certified with a rating that is not compliant with a regional
standard. Conversely, an ICM cannot certify an individual combination
with a rating that is not compliant with a regional standard if the
individual combination includes a model of outdoor unit that an OUM has
certified with a rating that is compliant with a regional standard.
Issue 2: DOE requests comment on its proposed language in 429.16
related to allowable ICM ratings and compliance with regional
standards.
7. Reporting of Low-Capacity Lockout for Air Conditioners and Heat
Pumps With Two-Capacity Compressors
The current SEER and HSPF equations (4.1-1 and 4.2-1) in the DOE
test procedure for a CAC/HP having a two-capacity compressor require
different calculations of quantities depending on whether the test unit
would operate at low capacity, cycle between low and high capacity, or
operate at high capacity in response to the building load (see sections
4.1.3 and 4.2.3). To determine which calculations to use for units that
lock out low capacity operation at higher outdoor temperatures, the
outdoor temperature at which the unit locks out low capacity operation
must be known. Section 4.1.3 of Appendix M indicates that this
information must be provided by the manufacturer. Similarly, a two-
stage heat pump may lock out low capacity heating operation below a
certain lock-out temperature, as indicated in section 4.2.3 of Appendix
M. Therefore, DOE proposes to add language to require that the lock-out
temperatures for such systems for both cooling and heating modes be
provided in the certification report.
8. Represented Values of Cooling Capacity
In the November 2015 SNOPR, DOE proposed adding a requirement that
the represented values of cooling capacity and heating capacity must be
the mean of the values measured for the sample. In response, AHRI,
Lennox, JCI, Ingersoll Rand, Goodman, UTC/Carrier, Nortek, and Rheem
disagreed with the requirement that the represented capacity values
must be the mean of the tested values, and recommended that DOE allow
manufacturers to rate capacity conservatively. (CAC TP: AHRI, No. 70 at
p. 10; Lennox, No. 61 at p. 8, 15; JCI, No. 66 at p. 15-16; Ingersoll
Rand, No. 65 at p. 5; Goodman, No. 73 at p. 15; UTC/Carrier, No. 62 at
p. 8; Nortek, No. 58 at p. 6; Rheem, No. 69 at p. 8) The commenters
provided additional detail as summarized in the
[[Page 58173]]
June 2016 final rule. 81 FR 37014-15 (June 8, 2016).
After reviewing the comments, in the June 2016 final rule DOE
required the represented value of cooling (or heating) capacity to be a
self-declared value that is no less than 95 percent of the mean of the
cooling (or heating) capacities measured for the units in the sample
selected for testing or of the output simulated by the AEDM. DOE stated
that this would allow manufacturers the flexibility to derate capacity
with conservative values as requested by multiple commenters, while
still providing consumers with information that is reasonably close to
the performance they may expect when purchasing a system. Id.; 10 CFR
429.16(b)(3) and 429.16(d).
Upon review, DOE has determined that the regulatory text adopted
allows for unlimited overrating of capacity but only underrating of 5
percent. Consequently, in this SNOPR, DOE is proposing to revise the
regulatory text in three locations (10 CFR 429.16(b)(3), 10 CFR
429.16(d), 10 CFR 429.70(e)(5)(iv)) to allow a one-sided tolerance on
cooling and heating capacity that allows underrating of any amount but
only overrating up to 5 percent (i.e., the certified capacity must be
no greater than 105 percent of the mean measured capacity or the output
of the AEDM), as intended in the June 2016 final rule. As adopted in
that final rule, DOE would still use the mean of the measured
capacities in its enforcement provisions.
Issue 3: DOE requests comment on its proposal to allow a one-sided
tolerance on represented values of cooling and heating capacity that
allows underrating of any amount but only overrating up to 5 percent.
B. Proposed Amendments to Appendix M Testing To Determine Compliance
With the Current Energy Conservation Standards
In this SNOPR, DOE proposes revisions to appendix M to subpart B of
10 CFR part 430. This section provides a discussion of those proposed
changes. DOE proposes to make these changes to Appendix M effective 30
days after publication of a final rule in the Federal Register.
Representations related to the efficiency of CAC/HP basic models must
be based on testing in accordance with the final rule procedures not
later than 180 days following publication of the final rule.
1. Measurement of Off Mode Power Consumption: Time Delay for Units With
Self-Regulating Crankcase Heaters
DOE finalized an off-mode test procedure in the June 2016 final
rule. 81 FR, 36991, 37022-5 (June 8, 2016). However, DOE recognizes
that the current regulations may not account for excessive variation in
the test results for units with self-regulating crankcase heaters or
for units where the crankcase heater power measurement could be
affected by the ambient temperature. These potential variations could
be due to the large thermal mass of the compressor and the resulting
time required for the compressor temperature to reach equilibrium.
Because the power input of a self-regulating heater would depend on the
compressor temperature, the test result would depend on the temperature
of the unit just prior to the test. If conducted shortly after the B
test, which is one of the steady-state wet coil cooling-mode tests
conducted in an 82 [deg]F ambient temperature, the compressor would
still be quite warm, and the measured power input would be
significantly lower than if the test were conducted after the
compressor equilibrates with the surrounding space temperature. DOE
proposes further revision to the test procedure to resolve this issue.
The proposal in this section would not impact the measured off-mode
power input beyond potentially reducing variation in the measured
result.
In the off-mode test procedure established in the June 2016 final
rule, DOE established a test method for units with self-regulating
crankcase heaters that called for start of the test in a room
conditioned to 82 [deg]F temperature, with the compressor at a
temperature no lower than 81 [deg]F. The room temperature is then
adjusted at a rate of change of no more than 20 [deg]F per hour to
approach 72 [deg]F for conducting a first heater power measurement, and
then to approach a manufacturer-specified lower temperature, again at a
rate of change no more than 20 [deg]F per hour, before conducting the
second power measurement. 81 FR at 37022 (June 8, 2016). A half-hour
duration in the initial reduction in room temperature from 82 [deg]F to
72 [deg]F would be compliant with the prescribed 20 [deg]F maximum
temperature reduction rate. However, DOE testing shows that the time
constant for compressor cooldown, or for approach to equilibrium of the
power input a self-regulating crankcase heater attached to a
compressor, is much longer than a half-hour. This issue would be
exacerbated if the compressor has a sound blanket. Self-regulating
crankcase heaters draw less power when they are warmer. Hence, if the
temperature cooldown from 82 [deg]F is initiated when the compressor is
hot (e.g., after running the B test), the compressor will still be very
warm when the test is conducted, and the measured power input will be
lower than for a test initiated with a compressor at the minimum 81
[deg]F.
To determine the reasonable delay time for units to reach thermal
equilibrium, DOE conducted tests using a 5-ton residential condensing
unit. DOE connected a self-regulating crankcase heater to the
compressor and measured heater power input, compressor shell
temperature, and ambient temperature. DOE observed cooldown behavior
and the corresponding increase in heater input power in a 60 [deg]F
environment both with and without a sound blanket covering the
compressor after initially preheating the compressor to 120 [deg]F to
simulate warmup associated with refrigeration system operation. DOE
used an exponential equation for the power input to the heater as a
function of time to fit to the test data. The time constant for
approach to equilibrium (time for the difference between the power
input and the value it would attain after an infinite amount of time to
drop by 63 percent) DOE observed in the tests was approximately 2 hours
for tests without the sound blanket (bare shell) and 4 hours for tests
with the sound blanket. DOE also observed that the crankcase heater
power input generally approached to within 10 percent of its final
value after passage of about two time constants (4 hours for bare-shell
testing and 8 hours for sound blanket testing).
Based on the testing and analysis described in this preamble, DOE
proposes adopting a time delay for testing units with self-regulating
crankcase heaters or crankcase heating systems in which the heater
control temperature sensor is affected by the heater. DOE proposes a 4-
hour time delay for units where the compressors have no sound blanket,
and an 8-hour time delay for units where the compressors do have sound
blankets. The delay would take place after the room temperature reaches
the lower target value and before making each of the power measurements
(P1x and P2x). Also, the proposal would eliminate
the 20 [deg]F per hour room temperature reduction rate limit for any
unit where ambient temperature can affect the measurement of crankcase
heater power because the roughly half hour required for the temperature
to transition at this rate from 82 [deg]F to 72 [deg]F would add
unnecessarily to the compressor's equilibration time--equilibration
would occur sooner if the ambient temperature more quickly drops to the
final value rather than approaching it slowly.
[[Page 58174]]
Issue 4: DOE seeks comments from interested parties about its
proposal to impose time delays to allow approach to equilibrium for
measurements of off-mode power for units with self-regulating crankcase
heaters. DOE requests comment regarding the 4-hour and 8-hour delay
times proposed for units without and with compressor sound blankets,
respectively.
2. Refrigerant Pressure Measurement Instructions for Cooling and
Heating Heat Pumps
In DOE's current test procedures at Appendix M, refrigerant
pressure measurement is required when using the refrigerant enthalpy
method as the secondary capacity measurement (see section 2.10.3 of 10
CFR part 430, subpart B, appendix M). Refrigerant pressure measurement
is also required for some methods for setting or confirming refrigerant
charge (see section 2.2.5 of 10 CFR part 430, subpart B, appendix M),
unless otherwise instructed by the manufacturer's installation
instructions.
DOE is aware that the pressure measurement devices may be installed
at a location where the refrigerant state switches between liquid and
vapor under different cooling and heating modes. In this case, the
actual refrigerant charge in the unit could be different under
different modes due to the transfer of refrigerant to and from the
extra internal volumes in the refrigerant pressure lines, connections,
and transducers or gauges.
DOE is also aware that the refrigerant charge in pressure
measurement systems may affect cyclic testing. In a cooling test, the
liquid refrigerant in the liquid refrigerant pressure measurement
system is cooler than the refrigerant in the condenser. For a system
with a fixed orifice expansion device, allowing the cooler refrigerant
from the pressure measurement systems to flow into the evaporator
before the fan delay ends could affect the cyclic performance.
These issues have the potential to impact test reproducibility and
repeatability, in particular for small capacity mini-split heat pump
systems with low system refrigerant charges, depending on the
differences in internal volumes of the tubing, connections, and
transducers, particularly from one laboratory to the next.
As part of the compressor calibration method, ASHRAE 37-2009
section 7.4.2 provides instructions for making refrigerant pressure
measurements. For equipment not sensitive to refrigerant charge, the
pressure measurement instruments may be connected via pressure
measurement lines to the refrigerant lines without requiring that any
preliminary tests be conducted to confirm that displacement of
refrigerant into the pressure lines does not affect performance. The
test standard sets a threshold for sensitivity to refrigerant charge,
indicating that for equipment that is not sensitive to the charge, the
refrigerant pressure lines must not affect the total charge by more
than 0.5%.
To limit the amount of refrigerant charge that can transfer to and
from the pressure measurement system, DOE proposes to require
manufacturers to limit the total internal volume of pressure lines and
pressure measurement devices connected at locations that can switch
states from liquid to vapor for different operating modes or
conditions. Based on the ASHRAE 37-2009 precedent, DOE selected a
maximum internal volume connected at these locations that would
represent at most 0.5 percent of the total system charge for the
lowest-charge systems for which DOE collected information. The proposed
maximum total internal volume of the pressure lines, connections and
gauges would be 0.25 cubic inches per 12,000 Btu/hr certified cooling
capacity. DOE selected this maximum volume based on a survey of
refrigerant charge in mini-split heat pumps with capacities ranging
from 9,000 to 33,000 Btu/hr.
DOE notes that the charge adjustment approach prescribed by ASHRAE
37-2009 for systems that are sensitive to refrigerant charge would not
resolve the issue of displacement of refrigerant into the pressure
lines because that approach is based on steady-state testing, for which
the displaced refrigerant would remain in the lines. The required
adjustment would add that same amount of refrigerant so that the charge
actively circulating in the refrigerant circuit would be the same as if
no pressure lines had been connected. In the present case, where
refrigerant would be displaced between heating and cooling mode or
between cycles of a cyclic test, simply adding the ``missing'' charge
would not resolve the issue.
The internal volume of pressure measurement lines and connections
can be determined using the tubing inner diameter or internal volume
values found on pressure gauge or transducer manufacturer specification
sheets. However, DOE is aware that the manufacturer specification
sheets may not provide the internal volume of pressure gauges or
pressure transducers, and they may not be easy to measure. Thus, DOE
proposes to use 0.1 cubic inches as the default internal volume for
each pressure transducer and 0.2 cubic inches for each pressure gauge,
if internal volume is not provided in specification sheets. DOE
proposes to include this requirement in section 2.2 of 10 CFR part 430,
subpart B, appendix M.
Issue 5: DOE requests comment on its proposal to limit the internal
volume of pressure measurement systems for cooling/heating heat pumps
where the pressure measurement location may switch from liquid to vapor
state when changing operating modes and for all systems undergoing
cyclic tests. DOE also requests comment specifically on (a) the
proposed 0.25 cubic inch per 12,000 Btu/h maximum internal volume for
such systems, and (b) the proposals for default internal volumes to
assign to pressure transducers and gauges of 0.1 and 0.2 cubic inches,
respectively.
3. Revised EER and COP Interpolation Method for Units Equipped With
Variable Speed Compressors
In the current DOE test procedure specified in section 3.2.4 and
3.6.4 of 10 CFR part 430, subpart B, appendix M, the building load is
determined as a function of temperature, for both cooling and heating.
Units equipped with variable speed compressors are tested at full,
intermediate and minimum speeds. In calculating SEER and HSPF for
variable speed units, there are three possible scenarios: (a) When the
building load requires less than the minimum-speed capacity, the unit
cycles at the minimum compressor speed to meet the load; (b) when the
load requires more than the maximum-speed capacity, the unit operates
constantly at full load; and (c) when the unit operates at an
intermediate speed to meet a building load that is between the minimum-
speed and maximum-speed capacities. Three outdoor temperatures are
calculated for cooling and/or heating units equipped with variable
speed compressors to bound the conditions in which scenario c would
apply. These three outdoor temperatures are the balance points
(temperatures at which the building load and delivered capacity are
equal) for operation at the tested minimum, intermediate, and full
compressor speeds. For all variable speed units operating in cooling
mode and non-multi-split variable speed units operating in heating
mode, the unit's EER and COP are calculated using quadratic functions.
These quadratic functions are determined based on the EER or COP
evaluated for the three calculated outdoor temperatures representing
the minimum, intermediate, and full speed balance points.
[[Page 58175]]
In a final rule published October 22, 2007, DOE adopted a different
approach for multi-split heat pumps. 72 FR 59906 (October 2007 Final
Rule). DOE determined in that final rule that the quadratic fit would
not be well-suited for multi-split units because the intermediate speed
initially defined for variable-speed units is not likely the peak
efficiency point for multi-split units. (see 71 FR 41320, 41325 (July
20, 2006)). In addition to allowing multi-split manufacturers some
flexibility in selecting intermediate speeds for testing, DOE also
adopted in the October 2007 final rule a two-piece linear relationship
to represent EER and COP vs. temperature, rather than the quadratic fit
used for other variable-speed units. 72 FR 59906 (Oct. 22, 2007).
As discussed in section III.C.3.d, AHRI provided variable speed and
two stage heat data (under a Non-Disclosure Agreement to DOE's
contractor) to allow evaluation of the impact on the HSPF differential
associated with the new heating load line equation. In reviewing AHRI's
variable speed heat pump heating test data, DOE's contractor discovered
that the quadratic interpolation in some cases provides very poor
estimation of COPs in the intermediate-speed operating range--in some
cases predicting higher or lower COP values than all of the measured
COP results. DOE has found similar issues with prediction of the
cooling EER using the quadratic function, although DOE has less cooling
mode data to review, and the most egregious errors in EER prediction
for cooling mode are not as bad as the observed COP errors.
Nevertheless, DOE believes such issues could very well cause
significant errors in calculation of SEER for variable-speed units.
In this SNOPR, DOE evaluated two alternative interpolation methods
for calculating SEER and HSPF for variable-speed CAC/HP in addition to
the current quadratic function approach: (1) The linear interpolation
method which currently applies only to multi-split units in heating
mode (section 4.2.4.2 of 10 CFR part 430, subpart B, appendix M); and
(2) a bin-by-bin interpolation method. The bin-by-bin method uses
interpolation of EER or COP for each temperature bin based on the
estimates of capacity and power input for the specific bin temperature
(EER is equal to cooling capacity divided by power input, while COP is
proportional to heating capacity divided by power input). Under the
bin-by-bin method, an interpolation factor is first calculated, which
represents the compressor operating speed needed to achieve balance
between house load and delivered capacity. For example, if, for the
specific temperature bin, the heating load is between the minimum-speed
capacity and the intermediate-speed capacity, the interpolation factor
is equal to the difference between the heating load and the minimum-
speed capacity divided by the difference between the intermediate-speed
capacity and the minimum-speed capacity. This factor is then applied to
the COP values to determine COP when operating at the speed needed to
deliver the desired heating load. The desired load is divided by this
COP to determine power input. The interpolation is between the minimum
speed and the intermediate speed performance values if the load is
between the minimum and intermediate-speed capacities, or between the
intermediate speed and the full speed performance values, if the load
is between the intermediate and full speed capacities.
DOE found that HSPFs calculated with the current quadratic method
deviated from HSPFs calculated using the bin-by-bin method up to 7.4
percent and the linear interpolation method deviated up to 2.9 percent
from the bin-by-bin method. Calculations conducted for cooling mode
SEER showed that SEER for the quadratic method deviated from the SEER
calculated for the bin-by-bin method up to 2.5 percent. DOE believes
that the bin-by-bin interpolation method is the most accurate of the
three approaches (i.e., DOE's current quadratic approach and the two
alternative approaches considered for this SNOPR), because it is based
on the best estimates of performance at the different compressor speeds
for the specific ambient temperature considered for each bin. Hence,
DOE proposes to require use of the bin-by-bin interpolations for all
variable speed units (including variable-speed multi-split and multi-
head mini-split systems), to calculate performance when operating at an
intermediate compressor speed to match the building cooling or heating
load. Because DOE believes that the bin-by-bin method is the most
accurate, DOE does not propose for all variable-speed systems to adopt
the linear approach currently used for multi-split systems. DOE would
implement this change by revising the intermediate speed EER and COP
equations in section of 4.1.4.2 and 4.2.4.2 of appendix M of 10 CFR
part 430 subpart B.
Issue 6: DOE requests comment on the proposal to require the use of
a bin-by-bin method to calculate EER and COP for intermediate-speed
operation for SEER and HSPF calculations for variable-speed units.
4. Outdoor Air Enthalpy Method Test Requirements
In DOE's current test procedure in Section 2.10 of appendix M to
subpart B of part 430, the outdoor air enthalpy method is an allowable
secondary test method for split systems and single-package units. DOE
currently requires that the outdoor air-side test apparatus be
connected to the outdoor unit and used for measurements for the outdoor
air enthalpy method during the ``official'' test. Additionally, DOE
requires a preliminary test be conducted prior to conduct of the
official test, in which the unit operates without the outdoor air-side
test apparatus connected. After operating without the apparatus, the
apparatus is connected, and the apparatus exhaust fan speed is adjusted
until performance is verified as consistent with performance prior to
attaching the apparatus. Specifically, the unit must operate for 30
minutes without the apparatus connected, followed by at least five
consecutive readings with the apparatus connected (with measurements
taken at one-minute intervals). The apparatus exhaust fan speed must be
adjusted so that the averages for the evaporator and condenser
temperatures, or the saturated temperatures corresponding to the
measured pressures, agree within 0.5 [deg]F between the
tests with and without the apparatus connected. Additionally, a
preliminary test is only required prior to the first steady-state
cooling mode test and the first steady-state heating mode test, as long
as the outdoor fan operates during all cooling mode steady-state tests
at the same speed and during all heating mode steady-state tests at the
same speed. However, the test procedure requires that a preliminary
test be conducted prior to each cooling mode test where a different fan
speed is used, and a similar requirement applies for heating mode
tests.
The outdoor air enthalpy method includes two steps in order to
verify the capacity determined from the indoor air enthalpy method
during the official test. However, DOE is concerned that the tolerances
on achieving the same condensing and evaporating conditions in the
tests with and without the airflow measurement apparatus attached
inherently introduces variability to the test results that could be
eliminated by shifting to an official test with the apparatus not
attached. DOE proposes to make such a change for the official test.
In this SNOPR, DOE proposes to require two-step measurements in the
[[Page 58176]]
outdoor air enthalpy method only for cooling and heating mode tests
that currently require preliminary tests (i.e., the first cooling mode
and heating mode tests, and any cooling mode and heating mode tests
where a different outdoor fan speed is used). For example, if the unit
uses a different outdoor fan speed for each test, the two-step approach
would be required for each test condition. On the other hand, if the
unit is a single-capacity unit and the outdoor fan uses the same fixed
speed for all tests, the two-step approach would be required only for
the A and H1 tests. DOE proposes that for all cooling and heating mode
tests, a 30-minute test be conducted without the outside-air apparatus
connected (``non-ducted'' test). For tests that do not require
measurements for the outdoor air enthalpy method, this 30-minute test
non-ducted test would constitute the official test. For tests that do
require measurements using the outdoor air enthalpy method, DOE
proposes to maintain the current approach, except for changing
designation of what constitutes the official test. First, the current
30-minute preliminary test would be conducted without the outside-air
apparatus attached (now the ``non-ducted'' test). Next, the outside-air
apparatus would be attached. For this test, now termed the ``ducted''
test, the airflow would be adjusted so that condensing and evaporating
conditions are matched within tolerances, and five consecutive readings
would be required (as is required for the current test) to verify the
primary capacity measurements. For the tests that require measurements
using the outdoor air enthalpy method, DOE proposes that the following
conditions must be met for the test to be considered valid:
(1) The energy balance specified in section 3.1.1 of appendix M to
subpart B of part 430 is achieved for the ducted test (i.e., compare
the capacities determined using the indoor air enthalpy method and the
outdoor air enthalpy method).
(2) The capacities determined using the indoor air enthalpy method
from the ducted and non-ducted tests cannot deviate more than 2.0
percent.
If the test is valid, the non-ducted test would be used as the
official measurement for the specific test condition.
DOE believes that use of the outdoor air enthalpy method for only
certain tests sufficiently measures and verifies the capacity
determined from the indoor air enthalpy method, and that losing the
benefit of two-step verification of the capacity determined during all
of the official tests is outweighed by the three following benefits to
DOE's proposal:
Better Representativeness of Field Use. First, attachment
of an apparatus for measurements for the outdoor air enthalpy method
inherently affects the airflow pattern for the condenser (for example,
by blocking any potential for partial recirculation of condenser
discharge air to the inlet) and adds external static pressure for the
outdoor fan to overcome. While DOE's procedure requires adjustment of
apparatus exhaust fan speed to achieve similar performance to operation
without the outdoor air-side apparatus, there is still a tolerance on
this deviation in performance. Also, it may be impossible to exactly
match no-discharge-duct performance--for example, if the discharge duct
blocks partial air recirculation, total condenser fan airflow may have
to be reduced to achieve the same condensing temperature, thus altering
the condenser fan operating point. Therefore, DOE believes that removal
of the requirement to connect the outdoor air-side test apparatus
during the official test would allow for performance that better
matches performance in the field.
Improved Test Reproducibility and Repeatability. Second,
to maintain similar performance to operation without the outdoor air-
side apparatus, DOE currently requires that the apparatus exhaust fan
speed be adjusted. Specifically, the averages for the evaporator and
condenser temperatures, or the saturated temperatures corresponding to
the measured pressures, must agree within 0.5 [deg]F of
the averages achieved when the apparatus was disconnected. However, if
the outdoor air-side apparatus is connected during the official test,
two different test labs could measure evaporate and condenser
temperatures that differ by up to 1.0 [deg]F when testing the same
unit. This variation could, in turn, affect the measured cooling and/or
heating capacity of the unit, and therefore would change the calculated
SEER and/or HSPF. DOE believes that removing the ducted test
requirement from the official test would reduce this variation in
performance and therefore improve the reproducibility and repeatability
of its test procedure.
Reduced Test Burden. Third, for cooling mode and heating
mode tests requiring a preliminary test, DOE's current test procedure
requires a 30-minute non-ducted test and 5-minute ducted test be
conducted as part of the preliminary test, in addition to the 30-minute
official test. However, in DOE's proposal, separate 30-minute tests
would not be required for the preliminary and official tests--only a
single 30-minute non-ducted test would be performed as the official
test, assuming the required tolerances and test conditions are met. DOE
expects this removal of a required test to reduce the burden of testing
units with the outdoor air enthalpy method as a secondary method.
Issue 7: DOE requests comment on its proposed modifications to
requirements when using the outdoor air enthalpy method as the
secondary test method, including its proposal that the official test be
conducted without the outdoor air-side test apparatus connected.
5. Certification of Fan Delay for Coil-Only Units
In the cyclic dry-coil cooling-mode tests, the current regulatory
text requires coil-only units to be tested with a time-delay relay.
Section 3.5.1 of the current Appendix M states that the automatic
controls that are normally installed with the test unit must govern the
OFF/ON cycling of the air moving equipment on the indoor side. (10 CFR
430 Subpart B, App. M, 3.5.1) Under that section, the manufacturer is
to control the indoor coil airflow for ducted coil-only units according
to the rated ON and/or OFF delays provided by the relay. However, DOE
understands that in typical installations, a time-delay relay, if it
exists, would be part of the furnace function. DOE reviewed furnace
product literature collected during the furnace fan rulemaking (see
Docket Number EERE-2010-BT-STD-0011) representing a broad range of
furnaces sold by major furnace manufacturers to determine whether they
have time-delay relays available for cooling mode when installed with
coil-only air conditioners. DOE found that in many furnace series, both
old and new, from multiple manufacturers, cooling time delays are
common, but they are exclusively used for the compressor off-cycle, and
they have varying time-delay durations. Thus, DOE concludes that coil-
only units are likely to be installed with time-delay relay control for
cooling, but that the duration of the delay varies by furnace. DOE is
proposing no change in the use of time delays for testing of coil-only
units, but proposes to amend its certification report requirements to
require coil-only ratings specify whether a time delay is included, and
if so, the duration of the delay used. DOE would use the certified time
delay for any testing to verify performance. Section 3.5.1 would
indicate that the time delay used for testing of a coil-only system
shall be as listed in the certification report.
[[Page 58177]]
Issue 8: DOE requests comments on its proposal to require
certification reports for coil-only units to indicate whether testing
was conducted using a time-delay relay to provide an off-cycle time
delay, and the duration of the time delay.
6. Normalized Gross Indoor Fin Surface Area Requirements for Split
Systems
DOE must establish test procedures that are reasonably designed to
measure energy efficiency during a representative average use cycle as
determined by DOE. (42 U.S.C. 6293 (b)(3)) DOE is aware that many
potential combinations of single-split-system condensing units and
indoor coils could be tested even if they are not typically installed
as a combination. Ratings of single-split-system coil-only
combinations, for which the outdoor unit and indoor unit are not
typically installed as a combination, would not be representative of an
average use cycle. The CAC/HP ECS Working Group discussed this concept
and the potentially undesirable impacts of rating combinations that are
not distributed in commerce or installed for consumers. Specifically,
the CAC/HP ECS Working Group addressed ratings based on a combination
using a blower coil indoor unit consisting of a low-efficiency
condensing unit paired with an indoor blower with unusually low input
power, a concept the participants referred to as a ``golden blower.''
Such a combination would result in an inflated rating for a low-
efficiency condensing unit that is not representative of its typical
installed performance. (CAC ECS: ASRAC Public Meeting, No. 87 at p. 88)
The concept of unrepresentative, high performance can apply to other
design aspects of indoor units, such as units with an indoor coil size
far larger than would be installed for the given system capacity. To
help ensure that the test procedure results in ratings that are
representative of average use, DOE proposes to include a provision that
would prevent testing certain combinations that are not representative
of single-split systems with coil-only indoor units that are commonly
distributed in commerce.
Specifically, DOE proposes to limit the normalized gross indoor fin
surface (NGIFS) for the indoor unit used for single-split-system coil-
only tests be no greater than 2.0 square inches per British thermal
unit per hour (sq.in./Btu/hr). NGIFS is equal to total fin surface
multiplied by the number of fins and divided by system capacity. An
NGIFS greater than 2.0 sq.in./Btu/hr indicates that the system combines
a low-capacity condensing unit with a high capacity indoor coil, e.g.,
a 1.5-ton condensing unit paired with a 5-ton indoor coil. First, a
house requiring a 1.5-ton air conditioner would be expected to have a
commensurately-sized furnace, and a much larger indoor coil may not fit
with the furnace or the existing available space. Second, such a
combination might have good rated efficiency, but would provide poor
dehumidification performance, due to the elevation of coil surface
temperature (potentially above incoming air dew point temperature)
associated with the large coil surface area. Because of the size
compatibility and poor dehumidification performance, DOE understands
that systems with an NGIFS greater than 2.0 sq.in/Btu/hr are not
typically installed.
DOE evaluated the NGIFS for a representative data set of single-
split-system coil-only combinations currently offered in the market to
set this value. DOE's dataset included close to 100 two, three, and
five-ton single-split-system coil-only combinations from multiple
manufacturers that represent a majority of market share and span the
available range of efficiency. Testing with a NGIFS no greater than 2.0
sq.in/Btu/hr would still reflect approximately 95 percent of the split-
system coil-only combinations reviewed by DOE. DOE understands a
single-split-system coil-only combination with an NGIFS that exceeds
2.0 sq.in/Btu/hr to be unrepresentative because it is unlikely to be
distributed in commerce, which is supported by the review of NGIFS
values for numerous rated combinations, as noted previously.
Issue 9: DOE requests comment on its proposal to limit the NGIFS of
tested coil-only single-split systems to 2.0 sq.in/Btu/hr.
7. Modification to the Test Procedure for Variable-Speed Heat Pumps
In the November 2015 SNOPR, DOE proposed several changes to the
test procedure for variable-speed heat pumps. First, DOE proposed that
the maximum compressor speed used for the test be fixed at the absolute
maximum speed at which the compressor operates for the given operating
mode (heating or cooling). In other words, the maximum compressor speed
used in different cooling mode test conditions would be the same, equal
to the absolute maximum speed used for cooling at any operating
condition. DOE proposed a similar approach for heating, allowing for a
different maximum speed than for cooling. 80 FR at 69307 (Nov. 9,
2015).
The June 2016 final rule discussed comments on this proposal,
several of which indicated that the compressors of variable speed heat
pumps very often operate at higher speeds at colder temperatures, which
can enhance measured HSPF. 81 FR at 37029 (June 8, 2016). The comments
indicated that for some of these heat pumps, the compressor cannot
operate in a 47 [deg]F ambient temperature at the same full speed that
it uses in a 17 [deg]F ambient temperature. Although DOE did not in
that final rule modify the test procedure to allow different compressor
speeds for the full-speed tests conducted at 17 [deg]F, 35 [deg]F, and
47 [deg]F ambient temperatures, DOE did acknowledge that addressing
this issue would improve the test method's representation of the
improved performance of variable speed heat pumps that use higher
speeds at lower temperatures, indicating that consideration would be
given to such a test procedure revision in the future.\7\ Id. In this
SNOPR, DOE proposes such a test procedure revision.
---------------------------------------------------------------------------
\7\ The June 2016 final rule also changed the terminology for
the highest compressor speed from ``maximum speed'' to ``full
speed,'' as requested by several comments responding to the November
2015 SNOPR. 81 FR at 37030 (June 8, 2016).
---------------------------------------------------------------------------
The possible adoption of a 2 [deg]F test for rating of variable
speed heat pumps was proposed in the November 2015 SNOPR. 80 FR 69323
(Nov. 9, 2015) It was also discussed during the CAC/HP ECS Working
Group meetings, ultimately leading to Recommendation #5 in the Term
Sheet, that a 5 [deg]F ambient temperature optional test be adopted for
variable speed heat pumps under the new Appendix M1. (CAC ECS: ASRAC
Term Sheet, No. 76 at p. 3) This proposed revision is discussed in
greater detail in section III.C.4. Because the Appendix M1 test
procedure changes would be required as the basis for efficiency
representations on the effective date of any new energy conservation
standards (January 1, 2023), the 5 [deg]F test for variable speed heat
pumps would not become an option for several years. Based on the
stakeholder comments discussed in this preamble, some variable-speed
heat pumps may be unable to operate as required by the appendix M
procedure as finalized by the June 2016 final rule. In order to resolve
this issue sooner than 2021, DOE proposes that the test procedure
revisions to address it be adopted in appendix M rather than appendix
M1. Hence, DOE proposes the following amendments for appendix M.
A 47 [deg]F full-speed test used to represent the heating
capacity would be required and designated as H1N. However,
the 47 [deg]F full-speed test would not have to be conducted using the
same compressor speed (determined based on revolutions per minute (RPM)
[[Page 58178]]
or power input frequency) as the full-speed tests conducted at 17
[deg]F and 35 [deg]F ambient temperatures, nor at the same compressor
speeds used for the full-speed cooling test conducted at 95 [deg]F. For
Appendix M, the compressor speed for the 47 [deg]F full-speed test
would be at the manufacturer's discretion, except that it would have to
be no lower than the speed used in the 95 [deg]F full-speed cooling
test. Prior to the June 2016 final rule amendments, the heating
capacity was represented either by the H12 test (for which
the compressor speed guidance was not explicit), or, if a manufacturer
chose to conduct what was then the optional H1N test, this
latter test (using the same compressor speed as the full-speed cooling
mode test) represented the heating capacity. In the current proposal,
heating capacity would be represented only by the H1N test,
which would be mandatory, while the compressor speed would be at the
manufacturer's discretion within a range from the speed used for the 95
[deg]F full-speed cooling test to the speed used for the full-speed 17
[deg]F test.
The full-speed tests conducted at 17[emsp14][deg]F and
35[emsp14][deg]F ambient temperatures would still have to use the same
speed, which would be the maximum speed at which the system controls
would operate the compressor in normal operation in a 17[emsp14][deg]F
ambient temperature, although the 35[emsp14][deg]F full-speed test is
and would remain optional.
It would be optional to conduct a second full-speed test
at 47[emsp14][deg]F ambient temperature at the same compressor speed as
used for the 17[emsp14][deg]F test, if this speed is higher than the
speed used for the H1N test described in this preamble. This
test would be designated the H12 test. Because DOE does not
expect that an H1N test would ever use a higher compressor
speed than used for the full-speed 17[emsp14][deg]F test, the test
procedure would not provide for this situation.
If no 47[emsp14][deg]F full-speed test is conducted at the
same speed as used for the 17[emsp14][deg]F full-speed test,
standardized slope factors for capacity and power input would be used
to estimate the performance of the heat pump for the 47[emsp14][deg]F
full-speed test point for the purpose of calculating HSPF.
The capacity measured for the H1N test would be
used in the calculation to determine the design heating requirement.
Development of these proposals and decisions regarding their
details is explained further below.
As discussed in the June 2016 final rule, DOE believes that
extrapolations of performance to lower temperatures should be based on
tests conducted at the same speed and used to estimate performance
where there is a good expectation that the speeds are also the same or
at least not very different. Hence, DOE believes that calculation of
performance below 17[emsp14][deg]F must be based on a same-speed
extrapolation (or on an interpolation using measurements for a lower-
temperature test, such as for the proposed 5[emsp14][deg]F test
discussed in section III.C.4). For those heat pumps which cannot
operate in the 47[emsp14][deg]F ambient temperature at the same
compressor speed used for the 17[emsp14][deg]F full-speed test, DOE
proposes use of average performance trends to represent the
47[emsp14][deg]F test point so that a representative same-speed
extrapolation can be done.
DOE evaluated the 17[emsp14][deg]F-to-47[emsp14][deg]F same-speed
performance trends of heat pumps based on several sources including the
AHRI database, data for two stage and variable speed heat pumps
provided to DOE's contractor by AHRI during the CAC/HP ECS meetings,
and product data sheets for 51 single-package heat pumps. The ratios
for capacity and power input for the 17[emsp14][deg]F test condition as
compared to the 47[emsp14][deg]F test condition are presented in Table
III.4. The AHRI database provides capacity information for both
17[emsp14][deg]F and 47[emsp14][deg]F test conditions, but not power
input for both. DOE did not consider variable speed models from the
AHRI database in this analysis because of questions about whether the
compressor speeds were the same for both test conditions for tests of
these units. For the data provided by AHRI during the CAC/HP ECS
meetings, DOE evaluated the two stage units and the variable speed
units with a capacity ratio within a narrow range, to be sure that the
results for these units were based on use of the same speed for both
test conditions. Evaluation of the data for single-package units shows
that they have a significantly lower capacity ratio, but roughly the
same power input ratio, as compared with split systems. Consequently,
DOE is proposing in this SNOPR a different standard capacity slope
factor for single-package units.
Table III.3--Average Heat Pump Capacity and Power Input Ratios for
17[emsp14][deg]F and 47[emsp14][deg]F Tests
------------------------------------------------------------------------
Capacity ratio Power input ratio
Data source (17 [deg]F vs. (17 [deg]F vs. 47
47 [deg]F) [deg]F)
------------------------------------------------------------------------
AHRI Database, Single-Stage and 0.618 Not available.
Two stage.
Split-System......................
Single-Package.................... 0.558 ....................
Data Provided by AHRI During ASRAC .............. ....................
Meetings:
Two stage..................... 0.623 0.886.
Variable speed *.............. 0.637 0.875.
Data Sheets for Single-Package 0.557 0.874.
Units.
------------------------------------------------------------------------
* Just for VS units with capacity ratio between 0.59 and 0.67,
indicating high probability that compressor speed was the same for
both 17[emsp14][deg]F and 47[emsp14][deg]F tests.
Based on the reviewed data, DOE selected capacity ratios equal to
0.62 for split systems and 0.56 for single-package units in order to
calculate capacity slope factors. Also, DOE selected 0.88 as the power
input ratio to use for calculating the power input slope factor. DOE
proposes adopting slope factors that would be multiplied by the
capacity or power input measured for the 17[emsp14][deg]F ambient
temperature in order to obtain the slope of the evaluated parameter per
degree temperature rise. For example:
Capacity Slope = Qh\k=2\(17) * CSF
Where:
Capacity Slope is the change in capacity per change in temperature
in Btu/h-[deg]F,
Qh\k=2\(17) is the capacity measured in the
H32 Test in Btu/h, and
CSF is the Capacity Slope Factor in 1/[deg]F.
The CSF is calculated from the selected capacity ratio as
follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.001
Where CR is the capacity ratio.
The resulting values for the capacity slope factors are 0.0204/
[deg]F for split
[[Page 58179]]
systems and 0.0262/[deg]F for single-package systems. DOE adopted a
similar approach for development of the Power Slope Factor (PSF), which
is calculated to be 0.00455/[deg]F for all systems.
DOE proposes use of these slope factors for any variable speed heat
pumps for which the 47[emsp14][deg]F full-speed test cannot be
conducted at the same speed (represented by RPM or power input
frequency) used in the 17[emsp14][deg]F full-speed test. The slope
factors would be used for calculation of representative capacity and
power for operation at 47[emsp14][deg]F ambient temperature for the
purposes of calculating HSPF.
As mentioned in this preamble, DOE proposes that the
17[emsp14][deg]F test be conducted using the maximum speed at which the
system controls would operate the compressor during normal operation in
this ambient temperature. This would help to ensure that the test
procedure be representative of field operation, since, for cold
temperatures close to 17[emsp14][deg]F, the heat pump would be expected
to be operating at full speed to satisfy the high heating loads
expected for these temperatures. Further, DOE proposes that the
35[emsp14][deg]F full-speed test, if conducted, use the same compressor
speed as the 17[emsp14][deg]F test, so that the impact of frosting and
defrost for this test is not masked by an adjustment in compressor
speed.
Issue 10: DOE requests comments on its proposal to require that
full-speed tests conducted in 17[emsp14][deg]F and 35[emsp14][deg]F
ambient temperatures use the maximum compressor speed at which the
system controls would operate the compressor in normal operation in a
17[emsp14][deg]F ambient temperatures. DOE requests comment on the
proposed approach of using standardized slope factors for calculation
of representative performance at 47[emsp14][deg]F ambient temperature
for heat pumps for which the 47[emsp14][deg]F full-speed test cannot be
conducted at the same speed as the 17[emsp14][deg]F full-speed test.
Further, DOE requests comment on the specific slope factors proposed,
and/or data to show that different slope factors should be used.
In addition, DOE proposes that the H1N test, at
47[emsp14][deg]F ambient temperature, be conducted to represent nominal
heat pump heating capacity, but that there would be no specific
compressor speed requirement associated with it for Appendix M, except
that it be no lower than the speed used for the 95[emsp14][deg]F full-
speed cooling test. If the H1N test does not use the same
speed as is used for the 17[emsp14][deg]F full-speed heating test, it
would affect the HSPF calculation only through its influence on the
design heating requirement, since the standardized slope factors would
be used to represent full-speed heat pump performance. DOE proposes
that the 47[emsp14][deg]F full-speed test used to represent heat pump
capacity would use the same maximum compressor speed that the control
system would use during normal operation in 47[emsp14][deg]F ambient
temperatures in Appendix M1 (see section III.C.4) However, proposing
flexibility in the selection of compressor speed for the test would be
more consistent with the recent approach for measuring nominal heating
capacity (prior to publication of the June 2016 final rule) because
compressor speed requirements on the H12 test may not have
been clearly defined at that time (see Appendix M to subpart B of part
430 as of January 1, 2016).
Issue 11: DOE requests comments on its proposal to allow the full
speed test in 47[emsp14][deg]F ambient temperature that is used to
represent heat pump heating capacity, to use any speed that is no lower
than used for the 95[emsp14][deg]F full-speed cooling test for Appendix
M.
8. Clarification of the Requirements of Break-in Periods Prior to
Testing
In the June 2016 final rule, DOE maintained its proposal from the
November 2015 SNOPR to allow manufacturers the option of specifying a
break-in period to be conducted prior to testing under the DOE test
procedure. DOE limited the optional break-in period to 20 hours, which
is consistent with the test procedure final rule for commercial HVAC
equipment (10 CFR 431.96). The duration of the compressor break-in
period, if used, must be included in the certification report for CAC/
HP (10 CFR 429.16). DOE also adopted the same provisions as the
commercial HVAC rule regarding the requirement for manufacturers to
record the use of a break-in period and its duration as part of the
test data underlying their product certifications, the use for testing
conducted by DOE of the same break-in period specified in product
certifications, and use of the 20 hour break-in period for DOE testing
of products certified using an AEDM. 81 FR at 37033 (Jun. 8, 2016).
Section 3.1.7 of Appendix M, ``Test Sequence'' indicates that
manufacturers have the option to operate the equipment for a break-in
period on to exceed 20 hours, and that this break-in period must be
recorded in the test data underlying the certified rating if the
manufacturer uses a break-in period. DOE has made reporting of the
break-in period a certification report requirement. 81 FR at 37053
(June 8, 2016). Hence, the instructions to record the break-in period
in the test report is not necessary in section 3.1.7. Also, DOE intends
that tests conducted by third-party testing facilities should use the
break-in period that is certified and proposes to modify the language
to clarify that the certified break-in period is used for the test
(whether conducted by a manufacturer or other party). DOE also proposes
to clarify that each compressor should undergo the break-in according
to the certified number of hours, for units with multiple compressors.
Finally, DOE proposes to clarify that the break-in period should be
conducted prior to the first 30 minutes test data collection period as
required by the test methods in section 3 of Appendix M.
Issue 12: DOE requests comments on its clarifications regarding use
of break-in, including use of the certified break-in period for each
compressor of the unit, regardless of who conducts the test, prior to
any test period used to measure performance.
9. Modification to the Part Load Testing Requirement of VRF Multi-Split
Systems
In addition to the adopted portions of the AHRI Standard 1230-2010,
DOE proposed additional provisions in the November 2015 SNOPR for
testing of VRF Multi-Split Systems. This included a provision adopted
as part of section 2.2.3.a of Appendix M in the June 2016 final rule
requiring that for part load tests, the sum of the nominal heating or
cooling capacities of the operational indoor units be within 5 percent
of the intended system part load heating or cooling capacity. 81 FR at
37066 (June 8, 2016). DOE recognizes the intended system part load
heating or cooling capacity is not clearly defined in the test
procedure and that the sum of nominal capacities of the indoor units
may very well be higher than the system part load capacity during the
test (since the indoor units would be expected to be operating at part
load, less than their nominal capacity, during a part load test).
Therefore, DOE proposes to remove this 5 percent tolerance requirement.
Issue 13: DOE requests comments on removing from section 2.2.3.a of
Appendix M the 5 percent tolerance for part load operation when
comparing the sum of nominal capacities of the indoor units and the
intended system part load capacity.
10. Modification to the Test Unit Installation Requirement of Cased
Coil Insulation and Sealing
The June 2016 final rule provided instructions in 2.2.c of Appendix
M for uncased coils, including instructions
[[Page 58180]]
regarding the addition of internal insulation and/or sealing consistent
with manufacturer's instructions. The section ends with a requirement
that no extra insulating or sealing is allowed for cased coils. This
statement was intended to indicate that no extra internal insulating or
sealing is allowed. DOE believes that the statement as it stands may
suggest that sealing is not allowed between a cased coil and its
connections to inlet and outlet ducts. To prevent such confusion, DOE
proposes to remove the statement about cased coils.
Issue 14: DOE requests comment on whether removing the statement
about insulating or sealing cased coils in Appendix M, section 2.2.c
would be sufficient to avoid confusion regarding whether sealing of
duct connections is allowed.
C. Appendix M1 Proposal
The November 2015 SNOPR proposed to establish a new Appendix M1 to
Subpart B of 10 CFR part 430, which would be required to demonstrate
compliance with any new energy conservation standards. 80 FR 69278,
69397 (Nov. 9, 2015) In this SNOPR, DOE also proposes to establish a
new Appendix M1. The appendix would include all of the test procedure
provisions in Appendix M as finalized in the June 2016 final rule, all
of the proposed changes to Appendix M that are discussed in section
III.B, and all of the additional proposals discussed in this section
III.C, which would be included only in the new Appendix M1. DOE
proposes to make Appendix M1 mandatory for representations of
efficiency starting on the compliance date of any amended energy
conservation standards for CAC/HP (however, note that phase-in of
testing requirements for certain proposed new requirements for split
systems would be as discussed in section III.A.1).
1. Minimum External Static Pressure Requirements
Most of the CAC/HP in the United States use ductwork to distribute
air in a residence, using either a fan inside the indoor unit or housed
in a separate component, such as a furnace, to move the air. External
static pressure (ESP) for a CAC/HP is the static pressure rise between
the inlet and outlet of the indoor unit that is needed to overcome
frictional losses in the ductwork. The external static pressure imposed
by the ductwork affects the power consumed by the indoor fan, and
therefore also affects the SEER and/or HSPF of a CAC/HP.
a. Conventional Central Air Conditioners and Heat Pumps
The current DOE test procedure \8\ stipulates that certification
tests for ``conventional'' CACs and heat pump blower coil systems
(i.e., CACs and heat pump blower coil systems which are not small-duct,
high-velocity systems) must be performed with an external static
pressure at or above 0.10 in. wc. if cooling capacity is rated at
28,800 Btu/h or less; at or above 0.15 in. wc. if cooling capacity is
rated from 29,000 Btu/h to 42,500 Btu/h; and at or above 0.20 in. wc.
if cooling capacity is rated at 43,000 Btu/h or more.
---------------------------------------------------------------------------
\8\ Table 3 of 10 CFR part 430 subpart B appendix M.
---------------------------------------------------------------------------
DOE did not propose revisions to minimum external static pressure
requirements for conventional blower coil systems in the June 2010 test
procedure NOPR, stating that new values and a consensus standard were
not readily available.\9\ 75 FR 13223, 31228 (June 2, 2010). However,
between the June 2010 test procedure NOPR and the November 2015 test
procedure SNOPR, many stakeholders submitted comments citing data that
suggested the minimum external static pressure requirements were too
low and a value of 0.50 in. wc. would be more representative of field
conditions. These comments are summarized in the November 2015 test
procedure SNOPR. 80 FR 69317-18 (Nov. 9, 2015). Ultimately, in the
November 2015 SNOPR, DOE proposed to adopt, for inclusion into 10 CFR
part 430, subpart B, appendix M1, for systems other than multi-split
systems and small-duct, high-velocity systems, minimum external static
pressure requirements of 0.45 in. wc. for units with a rated cooling
capacity of 28,800 Btu/h or less; 0.50 in. wc. for units with a rated
cooling capacity from 29,000 Btu/h to 42,500 Btu/h; and 0.55 in. wc.
for units with a rated cooling capacity of 43,000 Btu/h or more. DOE
reviewed available field data to determine the external static pressure
values it proposed in the November 2015 test procedure SNOPR. DOE
gathered field studies and research reports, where publically
available, to estimate field external static pressures. DOE previously
reviewed most of these studies when developing test requirements for
furnace fans. The 20 studies, published from 1995 to 2007, provided
1,010 assessments of location and construction characteristics of CAC
and/or heat pump systems in residences, with the data collected varying
by location, representation of system static pressure measurements,
equipment's age, ductwork arrangement, and air-tightness.\10\ 79 FR 500
(Jan. 3, 2014). DOE also gathered data and conducted analyses to
quantify the pressure drops associated with indoor coil and filter
foulants.\11\ The November 2015 test procedure SNOPR provides a
detailed overview of the analysis approach DOE used to determine an
appropriate external static pressure value using this data. 80 FR
69318-19 (Nov. 9, 2015). DOE did not consider revising the minimum
external static pressure requirements for SDHV systems in the November
2015 test procedure SNOPR. DOE did, however, propose to establish a new
category of ducted systems, short duct systems, which would have lower
external static pressure requirements for testing. DOE proposed to
define ``short duct system'' to mean ducted systems whose indoor units
can deliver no more than 0.07 in. wc. external static pressure when
delivering the full load air volume rate for cooling operation. 80 FR
at 69314. DOE proposed in the November 2015 SNOPR to require short duct
systems to be tested using the minimum external static pressure
previously proposed in the June 2010 NOPR for ``multi-split'' systems:
0.03 in. wc. for units less than 28,800 Btu/h; 0.05 in. wc. for units
between 29,000 Btu/h and 42,500 Btu/h; and 0.07 in. wc. for units
greater than 43,000 Btu/h. 75 FR at 31232 (June 2, 2010)
---------------------------------------------------------------------------
\9\ In the June 2010 NOPR, DOE proposed lower minimum ESP
requirements for ducted multi-split systems: 0.03 in. wc. for units
less than 28,800 Btu/h; 0.05 in. wc. for units between 29,000 Btu/h
and 42,500 Btu/h; and 0.07 in. wc. for units greater than 43,000
Btu/h. 75 FR at 31232 (June 2, 2010).
\10\ DOE has included a list of citations for these studies in
the docket for the furnace fan test procedure rulemaking. The docket
number for the furnace fan test procedure rulemaking is EERE-2010-
BT-TP-0010.
\11\ Siegel, J., Walker, I., and Sherman, M. 2002. ``Dirty Air
Conditioners: Energy Implications of Coil Fouling'' Lawrence
Berkeley National Laboratory report, number LBNL-49757.
ACCA. 1995. Manual D: Duct Systems. Washington, DC, Air
Conditioning Contractors of America.
Parker, D.S., J.R. Sherwin, et al. 1997. ``Impact of evaporator
coil airflow in air conditioning systems'' ASHRAE Transactions
103(2): 395-405.
---------------------------------------------------------------------------
In response to the November 2015 SNOPR, Lennox supported DOE's
proposal to increase the minimum test static pressure to more
accurately reflect field installation conditions. Lennox recommended
that this level be set to 0.50 in. wc. for all capacities, commenting
that the single set point simplifies the test procedure, is consistent
with levels found in field studies, and avoids compliance issues
related to minimum static pressure settings based upon capacity. (CAC
TP:
[[Page 58181]]
Lennox, No. 61 at p. 11) Lennox also commented that improvements in
field practices to reduce installed static pressure in parallel with
optimizing products for lower static pressures are a more effective
measure to optimize field performance and reduce energy consumption.
Lennox commented that products optimized for increased static pressures
will likely result in increased energy consumption. (Lennox, No. 61 at
p. 11) Unlike Lennox, Rheem did not agree in its comments that the
assumption of poorly designed ductwork should be built into the test
procedure. (CAC TP: Rheem, No. 69 at p. 16)
Many interested parties supported the proposal to increase the
external static pressure requirement. NEEA and NPCC commented that the
minor adjustments on either side of 0.50 in. wc. on the basis of system
capacity would be a needless complication of the test procedure because
NEEA and NPPC's field data does not suggest any correlation between the
external static pressure a system faces and the system capacity. (CAC
TP: NEEA and NPCC, No. 64 at p. 8) The California IOUs recommended that
all capacities use 0.50 in. wc. to simplify testing. (CAC TP:
California IOUs, No. 67 at p. 2) ACEEE, NRDC, and ASAP fully supported
adopting 0.50 in. wc. for all units (in blower coil configuration), as
0.5 in. wc. would be closer to the levels found in thousands of
residential duct systems tested. (CAC TP: ACEEE, NRDC, ASAP, No. 72 at
p. 4)
Lennox and Rheem commented that DOE's assumption that a CAC system
would be poorly maintained, such as containing fouled coils and
filters, should not be built into the test procedure. (CAC TP: Lennox,
No. 61 at p. 19; Rheem, No. 69 at p. 16) Lennox further commented that
any accommodation for poor field conditions should be administered
equitably across all product types. (CAC TP: Lennox, No. 61 at p. 19)
Rheem also commented that although dirty filters and fouled coils can
increase system static, Rheem considers undersized duct work as the
leading cause of high pressure drop measured in field applications.
(CAC TP: Rheem, No. 69 at p. 16) Rheem believed that requiring higher
minimum external static pressure would reduce published ratings, which
could confuse installers and consumers. Rheem commented that a new
energy metric should be introduced that would distinguish ratings based
on appendix M from ratings based on appendix M1. The California IOUs
commented that, as shown in the ACCA Manual D,\12\ the filter pressure
drop value of 0.20 in. wc. is normal, and supported DOE's proposal.
(CAC TP: California IOUs, No. 67 at p. 6)
---------------------------------------------------------------------------
\12\ Manual D: Residential Duct Systems. Arlington, VA: Air
Conditioning Contractors of America (ACCA).
---------------------------------------------------------------------------
After discussions that included the concerns from the comments
summarized previously in this section, the CAC/HP ECS Working Group
members weighed in on appropriate minimum external static pressure
requirements. (CAC ECS: CAC/HP ECS Working Group meeting, No. 86 at pp.
31-128) Recommendation #2 of the CAC/HP ECS Working Group Term Sheet
states that the minimum required external static pressure for CAC/HP
blower coil systems other than mobile home systems, ceiling-mount and
wall-mount systems, low and mid-static multi-split systems, space
constrained systems, and small-duct, high-velocity systems should be
0.50 in. wc. for all capacities. (CAC ECS: ASRAC Term Sheet, No. 76 at
p. 2) In comments in response to the November 2015 SNOPR, Unico
supported the values discussed during the ASRAC meetings. (CAC TP:
Unico, No. 63 at p. 12) JCI and Carrier commented that this topic has
already been resolved through the ASRAC meetings.\13\ (CAC TP: JCI, No.
66 at p. 21; Carrier, No. 62 at p. 20)
---------------------------------------------------------------------------
\13\ The comment period for the November 2015 SNOPR was still
open during the CAC/HP ECS Working Group negotiations.
---------------------------------------------------------------------------
Based on DOE's analysis and consistent with the CAC/HP ECS Working
Group Term Sheet, DOE proposes to adopt, for inclusion into 10 CFR part
430, subpart B, appendix M1, for systems other than mobile home,
ceiling-mount and wall-mount systems, low and mid-static multi-split
systems, space-constrained systems, and small-duct, high-velocity
systems, a minimum external static pressure requirement of 0.50 in. wc.
DOE is aware that such changes will impact the certification ratings
for SEER, HSPF, and EER and is addressing such impact in the current
energy conservation standards rulemaking.\14\ For this reason, DOE is
not proposing to make this change in appendix M.
---------------------------------------------------------------------------
\14\ Docket No. EERE-2014-BT-STD-0048.
---------------------------------------------------------------------------
b. Non-Conventional Central Air Conditioners and Heat Pumps
In response to the November 2015 SNOPR and during the CAC/HP ECS
Working Group negotiations, DOE also received comment regarding the
minimum external static pressure requirements for mobile home systems,
ceiling-mount and wall-mount systems, low and mid-static multi-split
systems, space-constrained systems, and small-duct, high-velocity
systems. In its comments, First Co. proposed to reduce the minimum
static pressure for space-constrained and multi-family blower coils to
0.25 in. wc. or lower. (CAC TP: First Co., No. 56 at p. 2) The CAC/HP
ECS Working Group included in its Final Term Sheet Recommendation #2,
which is summarized in Table III.4 below. (CAC ECS: ASRAC Term Sheet,
No. 76 at p. 2)
Table III.4--CAC/HP ECS Working Group Recommended Minimum External
Static Pressure Requirement
------------------------------------------------------------------------
Minimum external static
Product description pressure (in. wc.)
------------------------------------------------------------------------
All central air conditioners and heat 0.50.
pumps except (2)-(7) below.
(2) Ceiling-mount and Wall-mount Blower TBD by DOE.
Coil System.
(3) Manufactured Housing Air Conditioner 0.30.
Coil System.
(4) Low-Static System.................... 0.10.
(5) Mid-Static System.................... 0.30.
(6) Small Duct, High Velocity System..... 1.15.
(7) Space Constrained.................... 0.30.
------------------------------------------------------------------------
Recommendation #1 of the CAC/HP ECS Working Group included
suggested definitions for distinguishing the CAC/HP varieties included
in Recommendation #2 (Table III.4) to enable the proper administration
of the CAC/HP ECS Working Group's recommended minimum external static
pressure requirements. Recommendation #1 stated:
Suggested definitions capture the intent of the Working
Group and DOE should adopt them as is or modify them in a manner that
captures the same intent.
For those definitions that contain a maximum external
static pressure requirement, the unit's maximum external static
pressure would be determined using a dry coil test without electric
heat installed and without an air filter installed at the unit's
certified airflow, or, if the airflow is not certified, at an airflow
of 400 cfm per ton of certified capacity.
For those condensing units distributed in commerce with
different indoor unit combinations, each specific combination would
need to meet the applicable definition in order to be rated with the
associated static.
The CAC/HP ECS Working Group's recommended definitions are as
follows:
[[Page 58182]]
A ceiling-mount blower coil system is a split-system
central air conditioner or heat pump that contains a condensing unit
and an indoor unit intended to be exclusively installed by being
secured to the ceiling of the conditioned space, with return air
directly to the bottom of the unit (without ductwork), having an
installed height no more than 12 inches (not including condensate drain
lines) and depth (in the direction of airflow) of no more than 30
inches, with supply air discharged horizontally. The certified cooling
capacity must be less than or equal to 36,000 Btu/h.
A wall-mount blower coil system is a split-system central
air conditioner or heat pump that contains a condensing unit and an
indoor unit intended to be exclusively installed by having the back
side of the unit secured to the wall within the conditioned space, with
capability of front air return (without ductwork) and not capable of
horizontal airflow, having a height no more than 45 inches, a depth of
no more than 22 inches (including tubing connections), and a width no
more than 24 inches. The certified cooling capacity must be less than
or equal to 36,000 Btu/h.
Manufactured housing air conditioner coil system is a
split-system air conditioner or heat pump that contains a condensing
unit with an indoor unit that: (1) Is distributed in commerce for
installation only in a manufactured home with the home and equipment
complying with HUD Manufactured Home Construction Safety Standard 24
CFR part 3280; (2) has an external static pressure that must not exceed
0.4 inches of water; and (3) has an indoor unit that must bear a label
in at least \1/4\ inch font that reads ``For installation only in HUD
Manufactured Home per Construction Safety Standard 24 CFR part 3280.''
Note, manufacturers must certify which combinations are manufactured
housing air conditioner coil system.
Low-static system means a ducted multi-split or multi-head
mini-split system where all indoor sections produce greater than 0.01
and a maximum of 0.35 inches of water of external static pressure when
operated at the full-load air volume rate not exceeding 400 cfm per
rated ton of cooling.
Mid-static system means a ducted multi-split or multi-head
mini-split system where all indoor sections produce greater than 0.20
and a maximum of 0.65 inches of water of external static pressure when
operated at the full-load air volume rate not exceeding 400 cfm per
rated ton of cooling.
UTC/Carrier supported the low and medium static definitions as
presented during the CAC/HP ECS Working Group meetings, in place of the
short-duct unit definition DOE proposed in the November 2015 SNOPR.
(CAC TP: UTC/Carrier, No. 62 at p. 3-4,19) AHRI and Mitsubishi
recommended in their comments nearly identical definitions to those
recommended in the CAC/HP ECS Working Group term sheet. (CAC TP: AHRI,
No. 70 at p. 17; Mitsubishi, No. 68 at p. 2-3) Goodman generally
supported the comments made by industry during the initial meetings of
the CAC/HP ECS Working Group, in which additional sub[hyphen]categories
of ``short-ducted'' systems were proposed. Goodman recommended that DOE
only include CAC/HP ECS Working Group's definitions and modifications
to the test procedure in the ``M1'' test procedure and not part of
``M'' test procedure because the proposed modification to the test
procedure would increase the measured energy consumption for those
``short-ducted'' systems being marketed under the current ``M'' test
procedure. (CAC TP: Goodman, No. 73 at p. 6-7)
DOE agrees with the intent of Recommendation #1 and #2 of the CAC/
HP ECS Working Group Term Sheet. DOE recognizes that the CAC/HP
varieties included in these recommendations have unique installation
characteristics that result in different field external static pressure
conditions, and in turn, indoor fan power consumption in the field.
While conventional split systems are typically installed in attics or
basements and require long ductwork to deliver conditioned air to the
conditioned space, ceiling-mount systems, wall-mount systems, space-
constrained systems, low-static systems and mid-static systems are
installed in or in closer proximity to the spaces they condition,
typically requiring shorter ductwork than conventional split systems.
The field external static pressure for these non-conventional systems
is lower than the external static pressure for conventional split
systems as a result. In this SNOPR, DOE proposes to adopt the CAC/HP
ECS Working Group recommended minimum external static pressure
requirements for space-constrained systems, low-static systems, and
mid-static systems to be more reflective of field conditions for these
reasons, with one modification. DOE understands that when some space-
constrained outdoor units are paired with conventional indoor units,
the minimum external static pressure requirement for space constrained
systems recommended by the CAC/HP ECS Working Group, 0.30 in. wc.,
would not be appropriate for these installations. Therefore, DOE also
proposes to limit the CAC/HP ECS Working Group recommended minimum
external static pressure requirement for space-constrained systems only
to space-constrained indoor units and single-package space-constrained
units.
The CAC/HP ECS Working Group tasked DOE with the determination of
the appropriate minimum external static pressure for ceiling-mount and
wall-mount systems. During the CAC/HP ECS Working Group meetings,
manufacturers of these systems suggested a minimum external static
pressure requirement of 0.30 in. wc. (CAC ECS: CAC/HP ECS Working Group
meeting, No. 88 at p. 31) However, the CAC/HP ECS Working Group did not
adopt this as a recommendation primarily due to lack of time to
thoroughly review the subject. DOE proposes to specify a minimum
external static pressure requirement of 0.30 in. wc. for ceiling-mount
and wall-mount systems, consistent with manufacturers' recommendations.
Mobile home \15\ systems also have lower field external static
pressure than conventional split systems. Mobile home systems are
installed in homes that meet the HUD Manufactured Home Construction
Safety Standard 24 CFR part 3280, which includes a maximum threshold of
0.30 in. wc. for the restrictiveness of ductwork. Consistent with these
HUD requirements, the CAC/HP ECS Working Group recommendation, and the
external static pressure requirements for mobile home systems in the
DOE furnace fan test procedure, DOE proposes to adopt 0.30 in. wc. as
the minimum external static pressure required for testing mobile home
central air conditioning and heat pump systems.
---------------------------------------------------------------------------
\15\ In previous rulemaking documents for the furnace fan test
procedure and, DOE used the term ``manufactured home'' to be
synonymous with ``mobile home,'' as used in some definitions in the
Federal Register. 10 CFR 430.2. DOE will use the term ``mobile
home'' in place of ``manufactured home'' hereinafter to be
consistent with the Federal Register definitions that use ``mobile
home'', such as for ``mobile home furnace.'' All provisions and
statements regarding mobile homes and mobile home products are
applicable to manufactured homes and manufactured home products.
---------------------------------------------------------------------------
In this SNOPR, DOE proposes to adopt the CAC/HP ECS Working Group
recommendations for minimum external static pressure requirements for
low-static and mid-static systems. By the definitions recommended by
the Working Group, these systems are not capable of producing external
static pressure significantly higher than the recommended minimum
external static
[[Page 58183]]
pressure requirements. Consequently, DOE expects that any system that
would meet these definitions would be incapable of properly
conditioning a home that has ductwork with an external static pressure
significantly higher than the proposed minimum.
The CAC/HP ECS Working Group did not recommend a change to the
current minimum external static pressure required (1.15 in. wc.) for
SDHV systems with a cooling or heating capacity between 29,000 to
42,500 Btu/h. However, the CAC/HP ECS Working Group recommended that
1.15 in. wc. also be used as the minimum external static pressure
requirement for SDHV systems of all other capacities. Using a single
minimum external static pressure value for all capacities of a given
CAC/HP variety is consistent with the approach recommended by the
Working Group for all CAC/HP varieties. DOE proposes to adopt the
Working Group recommendation for the minimum external static pressure
requirement for SDHV systems.
Table III.5 summarizes DOE's proposed minimum external static
pressure requirements.
Table III.5--Proposed Minimum External Static Pressure Requirements
------------------------------------------------------------------------
Minimum
external
CAC/HP Variety static
pressure (in.
wc.)
------------------------------------------------------------------------
Conventional (i.e., all central air conditioners and 0.50
heat pumps not otherwise listed in this table).........
Ceiling-mount and Wall-mount............................ 0.30
Mobile Home............................................. 0.30
Low-Static.............................................. 0.10
Mid-Static.............................................. 0.30
Small Duct, High Velocity............................... 1.15
Space-Constrained (indoor and single-package units only) 0.30
------------------------------------------------------------------------
Issue 15: DOE requests comments on the proposed minimum external
static pressure requirements.
DOE also agrees with the intent of the definitions recommended by
the CAC/HP ECS Working Group. DOE proposes to adopt those definitions
with minor modifications to make them consistent with other proposed
regulatory language. For example, DOE is proposing to replace the term
``condensing unit'' in the CAC/HP ECS Working Group recommended
definition for mobile home systems with the term ``outdoor unit'' to
ensure that the definition applies to both mobile home air conditioners
and heat pumps. DOE proposes to adopt the following definitions for the
CAC/HP varieties included in Recommendations #1 and #2 in the CAC/HP
ECS Working Group Term Sheet:
Ceiling-mount blower coil system means a split system for
which the outdoor unit has a certified cooling capacity less than or
equal to 36,000 Btu/h and the indoor unit is shipped with manufacturer-
supplied installation instructions that specify to secure the indoor
unit only to the ceiling of the conditioned space, with return air
directly to the bottom of the unit (without ductwork), having an
installed height no more than 12 inches (not including condensate drain
lines) and depth (in the direction of airflow) of no more than 30
inches, with supply air discharged horizontally.
Low-static blower coil system means a ducted multi-split
or multi-head mini-split system for which all indoor units produce
greater than 0.01 in. wc. and a maximum of 0.35 in. wc. external static
pressure when operated at the cooling full-load air volume rate not
exceeding 400 cfm per rated ton of cooling.
Mid-static blower coil system means a ducted multi-split
or multi-head mini-split system for which all indoor units produce
greater than 0.20 in. wc. and a maximum of 0.65 in. wc. when operated
at the cooling full-load air volume rate not exceeding 400 cfm per
rated ton of cooling.
Mobile home blower coil system means a split system that
contains an outdoor unit and an indoor unit that meet the following
criteria: (1) Both the indoor and outdoor unit are shipped with
manufacturer-supplied installation instructions that specify
installation only in a mobile home with the home and equipment
complying with HUD Manufactured Home Construction Safety Standard 24
CFR part 3280; (2) the indoor unit cannot exceed 0.40 in. wc. when
operated at the cooling full-load air volume rate not exceeding 400 cfm
per rated ton of cooling; and (3) the indoor unit and outdoor unit each
must bear a label in at least \1/4\ inch font that reads ``For
installation only in HUD manufactured home per Construction Safety
Standard 24 CFR part 3280.''
Wall-mount blower coil system means a split system for
which the outdoor unit has a certified cooling capacity less than or
equal to 36,000 Btu/h and the indoor unit is shipped with manufacturer-
supplied installation instructions that specify to secure the back side
of the unit only to a wall within the conditioned space, with the
capability of front air return (without ductwork) and not capable of
horizontal airflow, having a height no more than 45 inches, a depth of
no more than 22 inches (including tubing connections), and a width no
more than 24 inches (in the direction parallel to the wall).
c. Certification Requirements
DOE proposes to establish the certification requirements for
Appendix M1 to require manufacturers to certify the kind(s) of CAC/HP
associated with the minimum external static pressure used in testing or
rating (i.e., ceiling-mount, wall-mount, mobile home, low-static, mid-
static, small duct high velocity, space constrained, or conventional/
not otherwise listed). In the case of mix-match ratings for multi-
split, multi-head mini-split, and multi-circuit systems, manufacturers
may select two kinds. In addition, models of outdoor units for which
some combinations distributed in commerce meet the definition for
ceiling-mount and wall-mount blower coil system are still required to
have at least one coil-only rating (which uses the 441W/1000 scfm
default fan power value) that is representative of the least efficient
coil distributed in commerce with the particular model of outdoor unit.
Mobile home systems are also required to have at least one coil-only
rating that is representative of the least efficient coil distributed
in commerce with the particular model of outdoor unit. DOE proposes to
specify a default fan power value of 406W/1000 scfm, rather than 441W/
1000 scfm, for mobile home coil-only systems. Details of this proposal
are discussed in detail in section III.C.2.
Issue 16: DOE requests comment on the proposed definitions for
kinds of CAC/HP associated with administering minimum external static
pressure requirements.
d. External Static Pressure Reduction Related to Condensing Furnaces
In the November 2015 SNOPR, DOE requested comment on its proposal
to implement a 0.10 in. wc. reduction in the minimum external static
pressure requirement for air conditioning units tested in blower coil
(or single-package) configuration in which a condensing furnace is in
the airflow path during the test. This issue was also discussed as part
of the CAC/HP ECS Working Group negotiation process. ADP, Lennox, NEEA,
NPCC, California IOUs, Rheem, ACEEE, NRDC, and ASAP did not support the
proposal because it would make the ratings for units paired with
condensing furnaces less reflective of field energy use. (CAC TP: ADP,
No. 59 at p. 12; Lennox, No. 61 at p. 20; NEEA and NPCC, No. 64 at p.
8; California IOUs, No. 67 at p. 6; Rheem, No. 69 at p. 17; ACEEE,
NRDC, ASAP, No. 72 at
[[Page 58184]]
p. 4) JCI commented that this topic has already be resolved through the
CAC/HP ECS Working Group meetings. (CAC TP: JCI, No. 66 at p. 21)
Carrier commented to refer to the agreement on external static pressure
from the CAC/HP ECS Working Group and expressed the view that this
credit is contrary to better aligning the rating procedure with real
world data. (CAC TP: Carrier, No. 62 at p. 21) As Carrier and JCI point
out, Recommendation #2 of the CAC/HP ECS Working Group Term Sheet also
states that the proposed reduction in minimum external static pressure
required for units paired with condensing furnaces should not be used.
(CAC ECS: CAC/HP ECS Working Group Term Sheet, No. 76 at p. 2)
In light of public comments and the consensus of the CAC/HP ECS
Working Group, DOE is not proposing to adopt a reduced minimum external
static pressure requirement for air conditioning units tested in blower
coil (or single-package) configuration in which a condensing furnace is
in the airflow path during the test.
Issue 17: DOE requests comments on not including a reduced minimum
external static pressure requirement for blower coil or single-package
systems tested with a condensing furnace.
2. Default Fan Power for Rating Coil-Only Units
The default fan power value (hereafter referred to as ``the default
value'') is used to represent fan power input when testing coil-only
air conditioners, which do not include their own fans.\16\ In the
current test procedure, the default value is 365 Watts (W) per 1,000
cubic feet per minute of standard air (scfm) and there is an associated
adjustment to measured capacity to account for the fan heat equal to
1,250 British Thermal Units per hour (Btu/h) per 1,000 scfm (10 CFR
part 430, subpart B, Appendix M, section 3.3.d). The default value was
discussed in the June 2010 NOPR, in which DOE did not propose to revise
it due to uncertainty on whether higher default values would better
represent field installations. 75 FR 31227 (June 2, 2010). In response
to the June 2010 NOPR, Earthjustice commented that the existing default
values for coil-only units in the DOE test procedure were not supported
by substantial evidence. Earthjustice stated that external static
pressures measured from field data showed significantly higher values
than DOE's default values in its existing test procedure. (CAC TP:
Earthjustice, No. 15 at p. 2) In the November 2015 SNOPR, DOE proposed
to update the default value to be more representative of field
conditions (i.e., consistent with indoor fan power consumption at the
minimum required external static pressures proposed in the November
2015 SNOPR). In the November 2015 SNOPR, DOE used indoor fan electrical
power consumption data from product literature, testing, and exchanges
with manufacturers collected for the furnace fan rulemaking (79 FR 506,
January 3, 2014) to determine an appropriate default value for coil-
only products.\17\ (80 FR 69318)
---------------------------------------------------------------------------
\16\ See 10 CFR part 430, subpart B, appendix M, section 3.3.d.
\17\ For a complete explanation of DOE's methodology, see 80 FR
69278, 69319-20 (Nov. 9, 2015).
---------------------------------------------------------------------------
DOE calculated the adjusted default fan power to be 441 W/1000
scfm. In the November 2015 SNOPR, DOE proposed to use this value in
Appendix M1 of 10 CFR part 430 subpart B where Appendix M included a
default fan power of 365 W/1000 scfm. DOE proposed not to make such
replacements in Appendix M of 10 CFR part 430 subpart B.
In response to the November 2015 SNOPR, NEEA, NPCC, ACEEE, NRDC,
ASAP, and the California IOUs supported raising the coil-only test
default fan power to 441 W/1000 scfm to allow for more representative
ratings of units. (CAC TP: NEEA and NPCC, No. 64 at p. 8; ACEEE, NRDC,
ASAP, No. 72 at p. 4; California IOUs, No. 67 at p. 2) ACEEE, NRDC, and
ASAP also commented that they would be happy with 440 W/1000 scfm, as
the implied precision of using 441W/1000 scfm is artificial. (CAC TP:
ACEEE, NRDC, ASAP, No. 72 at p. 4)
The CAC/HP ECS Working Group also discussed the default value as
part of the negotiation process. Ultimately, the Working Group came to
a consensus on a recommendation for the default value. Recommendation
#3 of the CAC/HP ECS Working Group Term Sheet states that the default
fan power for rating the performance of all coil-only systems other
than manufactured housing products shall be 441W/1000 scfm. (CAC ECS:
ASRAC Working Group Term Sheet, No. 76 at p. 3)
Consistent with the CAC/HP ECS Working Group Term Sheet, DOE
maintains its previous proposal to use a default value of 441 W/1000
scfm for split-system air conditioner, coil-only tests. DOE proposes to
use this value in appendix M1 of 10 CFR part 430 subpart B in place of
the default fan power of 365 W/1000 scfm that has been used previously
in Appendix M.
Recommendation #3 of the CAC/HP ECS Working Group Term Sheet also
stated that DOE should calculate an alternative default fan power for
rating mobile home air conditioner coil-only units based on the minimum
external static pressure requirement for blower coil mobile home units
(0.30 in. wc.) that it suggested in recommendation #2 of the Term
Sheet. (CAC TP: ASRAC Working Group Term Sheet, No. 76 at p. 3) As
discussed in section III.C.1, the CAC/HP ECS Working Group included
this recommendation because HUD requires less restrictive ductwork for
mobile homes than for other types of housing, which reduces electrical
energy consumption of the indoor fan. The default value used to rate
coil-only mobile home systems should reflect this difference in field
energy consumption to improve the field representativeness of the test
procedure.
DOE agrees with the CAC/HP ECS Working Group's recommendation to
use a different default value for coil-only mobile home systems to
reflect the difference in ductwork and, in turn, external static
pressure of field installations of these systems. In this SNOPR, DOE
used the same aforementioned furnace fan power consumption data and
methodology to calculate the appropriate default value for mobile home
fan power consumption. However, in this case, DOE evaluated furnace fan
power consumption at 0.54 in. wc., which is the 0.30 in. wc.
recommended by the CAC/HP ECS Working Group plus 0.24 in. wc. to
account for filter and indoor coil pressure drop. The resulting average
indoor fan power consumption at the external static pressure
representative of mobile home systems is 8% lower than the average
indoor fan power consumption at the external static pressure
representative of conventional systems. Applying the 8% reduction to
the 441W/1000 scfm representing conventional indoor fan power
consumption yields 406 W/1000 scfm. Thus, DOE proposes to use 406 W/
1000 scfm as the default value for mobile home systems.
DOE notes that it used data from all of the furnaces in its
database to calculate this value, instead of only mobile home furnaces,
because its database includes a small number of mobile home furnaces
that do not represent all capacities or motor technologies. DOE
recognizes that including non-mobile home furnaces in this analysis may
bias the result. Due to the space constraints typical of mobile home
system installations, mobile home indoor units generally have more
restrictive cabinets compared to conventional indoor units, which would
be expected to increase the static pressure experienced by the indoor
fan
[[Page 58185]]
and, in turn, increase indoor fan power consumption. Consequently, DOE
expects that a default value calculated based on mobile home indoor fan
performance data may result in a higher default value for these systems
than the value proposed. In addition to the new default power values,
DOE proposes to adjust measured capacity to account for the fan heat
consistent with 441W/1000 scfm and 406 W/1000 scfm: 1,505 and 1,385
Btu/h per 1,000 scfm.
Issue 18: DOE requests comment on the proposed default fan power
value for coil-only mobile home systems. DOE also requests mobile home
indoor fan performance data for units of all capacities and that use
all available motor technologies in order to allow confirmation that
the proposed default value is a good representation for mobile home
units.
The DOE test procedure needs a definition for a mobile home coil-
only unit to appropriately apply the proposed default value for these
kinds of CAC/HP. DOE proposes to define mobile home coil-only unit as:
Mobile home coil-only system means a coil-only split
system that includes an outdoor unit and coil-only indoor unit and
coil-only indoor unit that meet the following criteria: (1) The outdoor
unit is shipped with manufacturer-supplied installation instructions
that specify installation only for mobile homes that comply with HUD
Manufactured Home Construction Safety Standard 24 CFR part 3280, (2)
the coil-only indoor unit is shipped with manufacturer-supplied
installation instructions that specify installation only in a mobile
home furnace, modular blower, or designated air mover that complies
with HUD Manufactured Home Construction Safety Standard 24 CFR part
3280, and (3) the coil-only indoor unit and outdoor unit each has a
label in at least \1/4\ inch font that reads ``For installation only in
HUD manufactured home per Construction Safety Standard 24 CFR part
3280.''
Issue 19: DOE requests comments on its proposed definition for
mobile home coil-only unit.
3. Revised Heating Load Line Equation
a. General Description of Heating Season Performance Factor (HSPF)
In the current test procedure, the HSPF determined for heat pumps
in heating mode is calculated by evaluating the energy usage of both
the heat pump unit (reverse refrigeration cycle) and the resistive heat
component when matching the house heating load for the range of outdoor
temperatures representing the heating season. The temperature range is
split into 5-degree ``bins'', and an average temperature and total
number of hours are assigned to each bin, based on weather data used to
represent the heating season for each climate region. An HSPF value can
be calculated for each climate region, but the HSPF rating is based on
Region IV. In the HSPF calculation, the amount of heating delivered is
set equal to the heating load, which increases as the bin temperature
decreases. In the current test procedure, the heating load is
proportional to the difference between 65 [deg]F and the outdoor (bin)
temperature. The heating load also is dependent on the size of the
house that the unit heats. For the HSPF calculation the size of the
house is set based on the capacity of the heat pump. For the current
test procedure, the heating load is proportional to the heating
capacity of the heat pump when operating at 47 [deg]F outdoor
temperature. The resulting relationship between heating load and
outdoor temperature is called the heating load line equation--it slopes
downward from low temperatures, dropping to zero at 65 [deg]F. The
slope of the heating load line equation affects HSPF both by dictating
the heat pump capacity level used by two stage or variable speed heat
pumps at a given outdoor temperature, and also by changing the amount
of auxiliary electric resistance heat required when the unit's heat
pumping capacity is lower than the heating load. The current test
procedure defines two heating load levels, called the minimum heating
load line and maximum heating load line. However, it is the minimum
heating load line in Region IV that is used to determine HSPF for
rating purposes.\18\
---------------------------------------------------------------------------
\18\ See 10 CFR part 430, subpart B, appendix M, Section 1.
Definitions.
---------------------------------------------------------------------------
b. HSPF Issues
Studies have indicated that the current HSPF test and calculation
procedure overestimates ratings because the current minimum heating
load line equation is too low compared to real world situations.\19\ In
response to the November 2014 ECS RFI, NEEA and NPCC commented that the
federal test procedure does a poor job representing balance point
temperatures and electric heat energy use in the case of heat pump
systems. They pointed out the inability of the test procedure to
capture dynamic response to heating needs, such as the use of electric
resistance (strip) heat during morning or afternoon temperature setup
(i.e., rewarming of the space after a thermostat setback period). They
also expressed concerns about capturing the use of electric resistance
heat during defrost cycles and at times when it shouldn't be needed,
such as when outdoor temperatures are above 30 [ordm]F. (CAC ECS: NEEA
& NPCC, No. 19 at p. 2)
---------------------------------------------------------------------------
\19\ Erbs, D.G., C.E. Bullock, and R.J. Voorhis, 1986. ``New
Testing and Rating Procedures for Seasonal Performance of Heat Pumps
with Variable speed Compressors'', ASHRAE Transactions, Volume 92,
Part 2B.
Francisco, Paul W., Larry Palmiter, and David Baylon, 2004.
``Understanding Heating Seasonal Performance Factors for Heat
Pumps'', 2004 Proceedings of the ACEEE Summer Study on Energy
Efficiency in Buildings.
Fairey, Philip, Danny S. Parker, Bruce Wilcox, and Matthew
Lombardi, 2004. ``Climatic Impacts on Seasonal Heating Performance
Factor (HSPF) and Seasonal Energy Efficiency Ratio (SEER) for Air-
Source Heat Pumps'', ASHRAE Transactions, Volume 110, Part 2.
---------------------------------------------------------------------------
DOE agreed with the NEEA and NPCC regarding balance point in the
November 2015 SNOPR and noted that the heating balance point determined
for a typical heat pump using the current minimum heating load line
equation in Region IV is near 17 [deg]F, while the typical balance
point is in the range 26 to 32 [deg]F, resulting from installing a
proper-sized unit based on the design cooling load according to ACCA
Manual S, 2014.\20\ The low heating balance point means that the test
procedure calculation adds in much less auxiliary heat than would
actually be needed in cooler temperatures, thus inflating the
calculated HSPF. Furthermore, the zero load point of 65 [deg]F ambient,
which is higher than the typical 50-60 [deg]F zero load point,\21\
causes the test procedure calculation to include more hours of
operation at warmer outdoor temperatures, for which heat pump operation
requires less energy input, again inflating the calculated HSPF. These
effects result in overestimation of rated HSPF up to 30% compared to
field performance, according to a paper by the Florida Solar Energy
Center (FSEC).\22\ For these reasons, DOE reviewed the choice of
heating load line equation for HSPF ratings and proposed to modify it
in the November 2015 SNOPR. 80 FR at 69320-2 (Nov. 9, 2015).
---------------------------------------------------------------------------
\20\ Manual S: Residential Equipment Selection (2nd ed., Ver.
1.00). (2014). Arlington, VA: Air Conditioning Contractors of
America (ACCA). pp. N7-N1.
\21\ Francisco, Paul W., Larry Palmiter, and David Baylon, 2004.
``Understanding Heating Seasonal Performance Factors for Heat
Pumps'', 2004 Proceedings of the ACEEE Summer Study on Energy
Efficiency in Buildings.
\22\ Fairey, Philip, Danny S. Parker, Bruce Wilcox, and Matthew
Lombardi, 2004. ``Climatic Impacts on Seasonal Heating Performance
Factor (HSPF) and Seasonal Energy Efficiency Ratio (SEER) for Air-
Source Heat Pumps'', ASHRAE Transactions, Volume 110, Part 2.
---------------------------------------------------------------------------
As part of its review for the November 2015 SNOPR, DOE considered a
2015
[[Page 58186]]
Oak Ridge National Laboratory (ORNL) study \23\ that examined the
heating load line equation for cities representing the six climate
regions of the HSPF test procedure in Appendix M. The study developed
modified regional heating load line equations, including a heating load
line equation for Region IV for calculation of a unit's HSPF. ORNL
conducted building load analyses using the EnergyPlus simulation tool
(see energyplus.net) using single-family Prototype Residential House
models based on building characteristics specified by the 2006
International Energy Conservation Code (2006 IECC). The study concluded
that a heating load line equation closer to the maximum load line
equation of the current test procedure and with a lower zero-load
ambient temperature would better represent field operation than the
minimum load line equation presently used for HSPF rating values.
---------------------------------------------------------------------------
\23\ ORNL, Rice, C. Keith, Bo Shen, and Som S. Shrestha, 2015.
An Analysis of Representative Heating Load Lines for Residential
HSPF Ratings, ORNL/TM-2015/281, July. (Docket No. EERE-2009-BT-TP-
0004-0046).
---------------------------------------------------------------------------
c. November 2015 SNOPR Heating Load Line Equation Proposal
In the November 2015 SNOPR, DOE proposed a new heating load line
equation based on the findings of the ORNL study:
[GRAPHIC] [TIFF OMITTED] TP24AU16.002
Tj = the outdoor bin temperature, [deg]F
Tzl = the zero-load temperature, [deg]F
TOD = the outdoor design temperature, [deg]F, which
varies by climate region
C = the slope (adjustment) factor
Qc(95 [deg]F) = the nominal cooling capacity at 95
[deg]F, Btu/h
The proposed equation included the following changes from the
current heating load line equation used for the HSPF calculation: \24\
---------------------------------------------------------------------------
\24\ In the current test procedure, for all climate regions but
Region V, the heating load based on minimum design heating
requirement as a function of outdoor temperature Tj is
Qh(47) * 0.77 * (65 - Tj)/60.
---------------------------------------------------------------------------
A zero-load temperature that varies by climate region, as
shown in Table III.6, and is 55 [deg]F for Region IV;
The building load is proportional to the nominal cooling
capacity at 95 [deg]F, Qc(95 [deg]F), as opposed to the
heating capacity at 47 [deg]F (except for heating-only heat pumps), to
reflect typical selection of cooling/heating heat pumps based on
cooling capacity; and
The slope (adjustment) factor, C, is 1.3 rather than 0.77;
The November 2015 SNOPR also proposed revised heating load hours
for each climate region, as shown in Table III.6. These hours are less
than the current heating load hours by the number of hours in the
temperature bins between the current and proposed zero-load
temperatures.
Table III.6--Climate Region Information Proposed in the November 2015 SNOPR
--------------------------------------------------------------------------------------------------------------------------------------------------------
Region No. I II III IV V VI
--------------------------------------------------------------------------------------------------------------------------------------------------------
Heating Load Hours, HLH................................. 562 909 1,363 1,701 2,202 * 1,974
Zero-Load Temperature, Tzl.............................. 60 58 57 55 55 58
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Pacific Coast Region.
The ORNL study developed heating load line equations consistent
with the similar equations of the current test procedure, using the
EnergyPlus heating and cooling loads calculated for the IECC 2006
building models developed for numerous cities of the climate regions of
interest. The approach sized the house based on the heat pump cooling
capacity rather than heating capacity, consistent with the sizing
approach prescribed for heat pumps in ACCA Manual S, which is also
based on cooling capacity. The study used the heat pump size
recommendations based on the design cooling load calculated by
EnergyPlus in its analysis. The design cooling load was determined for
the 0.4% cooling design day dry-bulb temperature based on a 24-hour
design day calculation using the heat balance method, which includes
the effects of house thermal mass on the peak load. For Climate Region
IV, used as the basis for the HSPF calculation, the study concluded
that the appropriate slope factor (C in the equation defined above) is
1.3.
In the November 2015 SNOPR, DOE also proposed to eliminate maximum
and minimum heating load line equations in an effort to focus on one
load level that would best represent heating. As mentioned, the
proposed heating load line equation is based on nominal cooling
capacity rather than nominal heating capacity, which is intended to
better reflect field installation practices than the basis on heating
capacity of the current test procedure. This approach also justifiably
benefits units with higher heating to cooling capacity ratios. Such
units would have improved HSPF ratings, reflecting the shift of more
heat from electric resistance to heat pumping. For the special case of
heating-only heat pumps, DOE proposed to maintain a sizing approach
based on heating capacity.
The ORNL study also evaluated the impact of the proposal on HSPF
ratings. Based on the results, DOE estimated that HSPF would be reduced
on average about 16 percent for single speed and two-stage heat pumps.
Consistent with the requirements of 42 U.S.C. 6293(e), DOE will account
for these changes in any proposed energy conservation standard, and
this test procedure proposal would not be required as the basis for
efficiency representations until the compliance date of any new energy
conservation standard.
d. Comments on the November 2015 SNOPR
Comments expressed by stakeholders on the proposed heating load
line equation, both in written form in response to the November 2015
SNOPR and verbally during the CAC/HP ECS Working Group meetings, are
summarized in the following paragraphs, organized by common themes.
[[Page 58187]]
Field Representativeness of the Heating Load Line Equation
One common theme raised in the comments concerned the field
representativeness of the data used to generate the proposed heating
load line equation. Unico expressed concern regarding the data
collected, requesting more time dedicated to research, particularly on
the northward shift of heat pump use despite the majority still being
sold in temperate climates. (CAC TP: Unico, No. 63 at p. 13) Lennox
expressed concern that the building stock used to evaluate the change
was outdated; the current load line should be aligned with the time
period of the standard. (CAC TP: Lennox, No. 61 at p. 20) During the
ASRAC meetings, Ingersoll-Rand expressed the same concern, adding that
the housing stock would continue to improve over time, driving the
slope down. (CAC ECS: ASRAC Public Meeting, No. 87 at p. 7) Ingersoll-
Rand also expressed reservations that the ORNL report relied on data
generated through simulations. (CAC ECS: ASRAC Public Meeting, No. 85
at p. 134).
Southern Company commented that basing the heating load line
equation exclusively on the 2006 IECC standard unrealistically assumes
flawless adoption and enforcement of building code standards and that
even future housing stock would be much less tight (i.e., would allow
much more infiltration of outdoor air than allowed by the IECC 2006
building code). (CAC ECS: ASRAC Public Meeting, No. 85 at p. 130) ACEEE
requested that simulation data generated in the ORNL report remain in
the discussion as the report represents a substantial contribution.
(CAC ECS: ASRAC Public Meeting, No. 85 at p. 134).
DOE understands the importance of developing the heating load line
equation with data that accurately represents field conditions and
operation. Regarding the relevancy of the 2006 IECC code, DOE maintains
that it is an appropriate representation of the housing stock in 2021
for the purposes of developing the heating load line equation. A
follow-up investigation by Lawrence Berkeley National Laboratory (LBNL)
examining RECS data corroborated this claim, showing that vintage
housing characteristics in 2021 would at best resemble new housing
characteristics in 2005. (CAC ECS: ASRAC Public Meeting, No. 85 at p.
81) DOE also maintains that EnergyPlus simulation results provide the
most accurate available picture of heating load requirements and their
dependence on independent parameters, (e.g., house design details, heat
pump sizing, typical weather patterns). While the data from some direct
field studies have been made available, none have included information
on heat pump sizing, a vital parameter for fitting a heating load line
curve to the data.
Impact on Model Differentiation
Another common theme expressed in the comments concerned the impact
of the proposed heating load line equation on model differentiation.
Mitsubishi suggested that the proposed changes would decrease
performance differentiation between single stage, two stage, and
variable speed systems and recommended DOE refrain from making any HSPF
changes. (CAC TP: Mitsubishi, No. 68 at p. 5) Rheem, JCI, and Carrier/
UTC concurred. (CAC TP: Rheem, No. 69 at p. 17; JCI, No. 66 at p. 13;
Carrier/UTC, No. 62 at p. 21) ACEEE added that, in the short-term,
accurately capturing relative performance of products should take
precedence over better reflecting field energy use if the two are
mutually exclusive. (CAC TP: ACEEE, No. 72 at p. 5) During the 2015-
2016 CAC/HP ECS Working Group meetings, AHRI expressed concern over the
lack of differentiation for variable speed products resulting from the
proposed heating load line equation. (CAC ECS: ASRAC Public Meeting,
No. 88 at p. 83) AHRI suggested a load line having a lower slope factor
(equal to 1.02) and presented an initial assessment of the impact of
both the DOE and AHRI proposals on product differentiation.
Additionally, Southern Company stressed the importance of encouraging
variable speed operation. (CAC ECS: ASRAC Public Meeting, No. 88 at p.
87).
To allow more detailed examination of this question, AHRI provided
test data to DOE's contractor under a non-disclosure agreement. The
data included performance measurements required to calculate HSPF using
the current and the proposed test procedures, for a number of two stage
and variable speed heat pumps. The calculations showed that the
proposed heating load line equation (1.3 slope factor and 55 [deg]F
zero-load temperature, with sizing based on the nominal cooling
capacity) would reduce the average HSPF difference between two stage
and variable speed models as compared to the current heating load line
equation (0.77 slope factor and 65 [deg]F zero-load temperature, with
sizing based on the nominal heating capacity) from 1 HSPF point
currently to roughly 0.35. DOE presented the methodology, findings,
conclusions, and implications of the analysis during the CAC/HP ECS
Working Group meetings. (CAC ECS: ASRAC Public Meeting, No. 63 at pp.
1-7).
DOE acknowledges the impact on differentiation of variable speed
heat pumps when calculating HSPF with a higher-slope factor heating
load line equation. However, EPCA requires test procedures to be
representative of the covered product's average use cycle--not that the
test procedure should favor particular design options. (42 U.S.C.
6292(b)(3)) DOE evaluated the proposed amendment with a focus on
accurately capturing field performance and believes that the
performance of models that clearly perform better in the field will be
captured and reflected in higher ratings when tested using a field-
representative efficiency metric. Nevertheless, DOE agrees that all
variable speed CAC/HP designs should be considered carefully in the
analysis to assure that the resulting test procedure fairly represents
their performance. As described below, ORNL has made some revisions in
its analysis that DOE has incorporated into a revised proposal that
improves the differentiation of variable speed heat pumps.
General Impact on Current HSPF Ratings
Comments on the overall impact of the proposed heating load line
equation on current HSPF ratings were also received. Carrier/UTC
reported a dramatic impact on all types of equipment, with reductions
in HSPF ranging from 15 to 25 percent as a result of the proposed
change in the November 2015 SNOPR. (CAC TP: Carrier/UTC, No. 62 at p.
21). Rheem commented that the proposal would reduce the HSPF of heat
pumps designed for southern market installations but did not clarify
why southern market heat pumps would be more affected. (CAC TP: Rheem,
No. 69 at p. 17).
DOE notes that, as indicated in the ORNL report, field studies have
shown that HSPF ratings based on the current test procedure may be
higher than actual performance. Hence, a reduction in the rating with
the revised test procedure would be consistent with observations of
actual heat pump field performance.
Sizing Based on Cooling Capacity
Other comments addressed DOE's proposal in the November 2015 SNOPR
to base the heating load line equation on cooling capacity rather than
heating capacity. NEEA and NPCC recommended that each heat pump be
assigned one of several heating load line equations based on heating
capacity and
[[Page 58188]]
balance point temperature. The appropriate heating load line equation
would be the one where the load at 30 [deg]F is most nearly equal to
the heat pump capacity at that temperature. (CAC TP: NEEA and NPCC, No.
64 at p. 11) However, ACEEE expressed support for the cooling capacity
basis during the ASRAC meetings. (CAC ECS: ASRAC Public Meeting, No. 88
at p. 92).
DOE understands that the balance point temperature for heat pumps
operating in the field is closer to 30 [deg]F than the 17 [deg]F
calculated for the current heating load line equation. For the heating
load line equation proposed in the November 2015 SNOPR, the average
balance point temperature is between 27 and 28 [deg]F. However, DOE
does not agree with NEEA and NPCC that heat pumps are typically sized
in the field based on heating capacity or the balance point
temperature. The sizing instructions outlined in ACCA Manual S
specifically state that ``heat pump equipment shall not be sized for
the design day heating load, or for an arbitrary thermal balance
point.'' DOE further understands that most heat pump units in the field
are sized based on cooling capacity as opposed to heat pump capacity,
which is consistent with the Manual S provision that ``heat pumps shall
be sized for cooling.'' \20\ To ensure field representativeness, DOE
proposes to maintain the approach that assumes heat pumps are sized
based on cooling capacity. This approach also benefits heat pump units
that have higher nominal heating to cooling capacity ratios by boosting
their HSPF.
Overall Regulatory Approach
Other comments concerned the regulatory approach regarding the
heating load line equation. Carrier/UTC encouraged DOE to go beyond
adjusting the heating load line equation, suggesting that the current
HSPF procedure does not adequately account for the benefits of variable
speed designs and that DOE should fund research into a completely new
procedure rather than applying corrections to the existing procedure by
changing the slope (CAC TP: Carrier/UTC, No. 62 at p. 21). Unico
suggested tabling the change until the next [CAC test procedure]
rulemaking when and if there would be support for changing it (CAC TP:
Unico, No. 63 at p. 13). JCI added that changing the temperature at
which the heating cyclic test is performed would be acceptable for
Appendix M1 but not for Appendix M. (CAC TP: JCI, No. 66 at p. 21).
ACEEE, NRDC, and ASAP proposed that AHRI, ASHRAE, DOE, and all
other stakeholders begin work now on a new ``clean-sheet'' rating
method for heat pumps, to be effective in the next rule after this
current rulemaking, as was recently done for water heaters. ACEEE,
NRDC, and ASAP stated that the current heat pump test method is
obsolete. It was developed when essentially all air-source heat pumps
were single-stage, and it appears that the present method is not
technology-neutral. According to ACEEE, NRDC, and ASAP, the current
test method should be revised to avoid penalizing advanced technologies
with the potential for higher efficiency, lower heating bills, and
reduced impact on winter grid peaks. ACEEE, NRDC, and ASAP recommended
that the test procedure for variable speed heat pumps be revised in a
future rulemaking to better reflect both the relative performance and
field energy use of this equipment. (CAC TP: ACEEE, NRDC, and ASAP, No.
72 at p. 5-6).
CAC/HP ECS Working Group members ultimately did not agree on a
resolution on the current heating load line equation regulatory
approach and agreed (as reflected in the Final Term Sheet
Recommendation #4) that DOE should make a final decision based on a
review of available information. (CAC ECS: ASRAC Term Sheet, No. 76 at
p. 3).
DOE acknowledges that another test method could be developed rather
than the current heating load line equation approach, but DOE does not
wish to propose a sweeping overhaul with this notice. DOE has taken the
steps agreed to in the ASRAC Final Term Sheet: To evaluate past
comments, improve the current analysis, and recommend an improved
heating load line equation based on a modest departure from the
existing approach. These steps taken leading up to the proposal in this
notice do not preclude DOE from evaluating more fundamental changes in
future rulemakings. DOE will continue to evaluate test methodologies
and will work with AHRI and other interested parties to evaluate other
approaches for testing heat pumps, determining the suitability of a
more fundamental change in a future rulemaking.
In response to JCI's comment regarding changes to the cyclic test,
DOE proposed in the November 2015 SNOPR to change the cyclic test
temperature for variable speed heat pumps only in Appendix M1 of 10 CFR
part 430 subpart B, and not to Appendix M of the same Part and
Subpart--DOE has not changed this aspect of the proposal in this
notice.
Heating Load Line Equation Slope Factor and Zero-Load Temperature
DOE also received specific recommendations on the heating load line
equation slope factor and zero-load temperature. In its comments,
Lennox opposed the heating load line equation slope factor change from
0.77 to 1.3 and recommended 1.02, citing better field
representativeness and wider product differentiation. (CAC TP: Lennox,
No. 61 at p. 12) During the ASRAC meetings, AHRI concurred, indicating
that (a) differentiation of variable speed products from two stage or
single stage products is better with the 1.02 slope factor, and (b) the
2012 IECC building requirements (for which the ORNL study showed a 1.02
slope) would better represent building stock in 2021 than the 2006 IECC
requirements. (CAC ECS: ASRAC Public Meeting, No. 88 at p. 83).
Regarding the heating load line equation zero-load temperature, the
California IOUs deferred to the CAC/HP ECS Working Group consensus,
generally accepting the 55 [deg]F zero-load temperature proposed in the
November 2015 SNOPR. (CAC TP: CA IOUs, No. 67 at p.7) JCI suggested
retaining the 65 [deg]F intercept and 0.7 slope factor of the current
test procedure. JCI argued for the 65 [deg]F intercept, referring to
evidence shared during the ASRAC meetings by Ingersoll-Rand, which JCI
indicated shows that heat pump operation does occur at these mild
conditions. JCI cited the negative impact on variable speed product
differentiation in supporting the lower slope factor. (CAC TP: JCI, No.
66 at p. 13).
In response to JCI's concerns outlined in this preamble, model
differentiation is not an EPCA requirement for test procedures.
Additional 35 [deg]F Test for Variable-Speed Heat Pumps
In the November 2015 SNOPR, DOE requested comment regarding the
appropriate approach for rating of variable-speed heat pumps if DOE
were not to adopt the proposed general heating load line equation. More
specifically, DOE was concerned about a potential inaccuracy associated
with the use of extrapolation of the minimum-speed performance measured
in 47 [deg]F and 62 [deg]F ambient temperatures for characterization of
heat pump performance below 47 [deg]F. In the November 2015 SNOPR, DOE
described two options. In Option 1, DOE would base performance on
minimum speed tests at 47 [deg]F and intermediate speed tests at 35
[deg]F, an approach which would involve no additional test burden. In
Option 2, DOE would require an additional minimum speed test at 35
[deg]F, which would likely be more accurate, at the cost of a higher
test burden.
In its comments, UTC/Carrier supported Option 1, because it would
[[Page 58189]]
not result in an increase in testing burden. (CAC TP: UTC/Carrier, No.
62 at p. 22) The California IOUs supported Option 2, and argued that
the additional test burden would be justified by the accuracy
improvements. (CAC TP: CA IOUs, No. 67 at p. 7) Johnson Controls asked
for more time to study both options, requesting that the discussion be
incorporated as part of the 2015-2016 ASRAC Negotiations. (CAC TP: JCI,
No. 66 at p. 22).
DOE has responded to the comments received and addressed this issue
in the context of the revised heating load line equation proposed in
section III.C.3.i of this notice.
e. Modifications to the 2015 ORNL Analysis
Following the conclusion of the CAC/HP ECS Working Group meetings,
ORNL reexamined key assumptions adopted in its 2015 report \23\ and
determined that three modifications would be beneficial in order to
improve the field representativeness of the analysis. The analysis
revisions and its results are described in an addendum to the 2015
report. (CAC TP: ORNL Report Addendum, No. 2) Ultimately the
modifications to the analysis led DOE to propose lower heating load
line equation slope factors (as discussed later in this section), which
addresses the comments of several stakeholders.
First, ORNL removed continuous mechanical ventilation as a feature
of the Prototype Residential Houses used in the analysis. While housing
models used in the initial analysis included continuous mechanical
ventilation, the 2006 IECC does not include that requirement, and DOE
believes that a prototype design without continuous mechanical
ventilation would be more representative of the average housing stock.
ORNL also modified the heat pump sizing approach used by the
analysis. In the 2015 study, the auto-sizing feature of EnergyPlus was
used. The auto-sizing feature uses a heat pump sized for the 0.4%
cooling design dry-bulb temperature, based on a 24-hour design day
calculation using the heat balance method, which includes the effects
of house thermal mass on the peak load. However, this approach does not
provide cooling capacity sufficient to meet the load for all hours of
the year. For the revised analysis, ORNL increased the heat pump size
so that cooling capacity would match or exceed the cooling load for all
hours of the year. This increases heat pumps capacities from 6% to 12%,
depending on the cities evaluated. This approach also better aligns the
sizing approach of the analysis with the sizing assumptions used in the
DOE test procedure, meaning that the heat pump's cooling capacity is
very close to 1.1 times the cooling load for 95 [deg]F ambient
temperature, consistent with equation 4.1-2 of the current test
procedure. ORNL also applied an additional 10% oversizing to heat pumps
for Region V, based on the observation that this adjustment is required
to achieve consistency with the 1.1 factor oversizing for cooling used
in the DOE test procedure.
The changes in heating load and heat pumps sizing led to reduction
in all of the regional heating load line equation slope factors.
Removing continuous ventilation reduced both the zero-load temperatures
and the heating load line equation slope factor across each region.
This change reduced the heating load line equation slope factor an
average (across all regions) of 5% while the zero-load temperatures
dropped on average by about 1-2 [deg]F. The adjustment in heat pump
size led to an average additional reduction in the slope factor of
roughly 9%, but did not change the zero-load temperatures. The
calculated heating load line equation slope factors of the modified
analysis vary sufficiently that DOE is proposing regional heating load
line equation slope factors as opposed to a single slope factor, using
Region IV as the basis for the HSPF rating. (CAC TP: ORNL Report
Addendum, No. 2)
f. DOE Proposal Based on Revised Analysis
Based on ORNL's revised findings, DOE has revised its heating load
line equation proposal from the November 2015 SNOPR. DOE introduced a
final adjustment to the slope factors developed by ORNL to address
variable speed systems. This aligns the analysis more closely with the
range of capacity recommended in ACCA Manual S, which allows
significantly more oversizing for variable-speed heat pumps than for
single speed or two-stage heat pumps. The range of recommended capacity
factor is 0.9 to 1.15 for single-stage heat pumps and 0.9 to 1.30 for
variable-speed. DOE recognizes that such oversizing is much more
tolerable with variable-speed heat pumps as compared to single-speed
heat pumps, due to their ability to better match mild-weather loads in
both heating and cooling seasons, and thus limit the inefficiencies
associated with cycling losses. Based on the averages of these ranges,
DOE calculated a size adjustment factor for variable-speed units equal
to (0.9 + 1.30) divided by (0.9 + 1.15), which equals 1.07, essentially
suggesting an additional 7 percent oversizing for variable-speed heat
pumps. Applying this to the heating load line equation analysis leads
to a corresponding reduction in the slope factors for variable-speed
products. DOE notes that for consistency, this oversizing would be
applied in seasonal performance calculations for cooling mode and for
heating mode.
With the analysis changes and the adjustment for variable-speed
models, DOE is proposing the following heating load line equation
changes from the November 2015 SNOPR:
The zero-load temperature would vary by climate region
according to the values provided in Table III.10, but remain at 55
[deg]F for Region IV;
The heating load line equation slope factor for single-
and two-stage heat pumps would vary by climate region, as shown in
Table III.7, and be 1.15 for Region IV; and
For variable speed heat pumps, the heating load line
equation slope factor would be 7 percent less than for single- and two-
stage heat pumps. It would vary by climate region, as shown in Table
III.7, and be 1.07 for Region IV;
DOE also revised the heating load hours based on the new zero load
temperatures of each climate region. The revised heating load hours are
also given in Table III.10.
Table III.7--Climate Region Information Proposed in This Notice
--------------------------------------------------------------------------------------------------------------------------------------------------------
Region No. I II III IV V VI *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Heating Load Hours...................................... 493 857 1280 1701 2202 1842
Zero-Load Temperature, Tzl.............................. 58 57 56 55 55 57
Heating Load Line Equation Slope Factor, C.............. 1.10 1.06 1.29 1.15 1.16 1.11
[[Page 58190]]
Variable Speed Slope Factor, CVS........................ 1.03 0.99 1.20 1.07 1.08 1.03
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Pacific Coast Region.
Following from this proposed heating load line equation change, DOE
also proposes in this SNOPR to require cyclic testing for variable
speed heat pumps be run at 47 [deg]F, rather than using the 62 [deg]F
ambient temperature that is required by the current test procedure (see
Appendix M, section 3.6.4 Table 11). The test would still be conducted
using minimum compressor speed. The modified heating load line cyclic
test at 47 [deg]F would be more representative of the conditions for
which cycling operation is considered in the HSPF calculation.
In addition, for variable-speed heat pumps, the SEER would be
calculated using a building load that is adjusted downwards by 7
percent, consistent with the heating load adjustment.
Issue 20: DOE requests comments on the adjustments to the proposals
for calculating HSPF for heat pumps and SEER for variable-speed heat
pumps.
g. Impact of DOE Proposal on Current HSPF Ratings and Model
Differentiation
DOE examined the impact of the present proposal on HSPF ratings
based on test results for 2, 3, and 5-ton heat pumps provided by AHRI.
Table III.8 presents the effect of different Region IV heating load
line equation slope factors on the average HSPF of two-stage and
variable speed units using these results. For two-stage units, the
average HSPF reduction from measurements using the current test
procedure to the current proposal would be 13.9%. For variable speed
products, the average reduction resulting from the current proposal
would be 15.3%. The purpose of the test procedure is to evaluate the
performance during a representative average use cycle. Nevertheless,
DOE believes that reasonable differentiation is still preserved with
the current proposal in this SNOPR. Further, DOE believes that heat
pumps with good heating mode performance will continue to stand out as
compared to heat pumps without good heating mode performance. The test
procedure changes proposed in this notice to allow higher speed
operation at lower temperature and for a 5 [deg]F optional test (see
section III.C.4) should allow for even greater differentiation for
variable-speed heat pumps with good heating performance.
Table III.8--Effect of Region IV Slope Factors on HSPF of Two-Stage (TS) and Variable Speed (VS) Models
----------------------------------------------------------------------------------------------------------------
Region IV slope factors
-------------------------------------------------------------------------------
2010 Final
rule * 1.02 1.15 1.30 2016 SNOPR **
----------------------------------------------------------------------------------------------------------------
Avg. TS HSPF.................... 9.49 8.47 8.17 7.80 8.17
Avg. VS HSPF.................... 10.93 9.44 8.95 8.44 9.26
Avg. HSPF Differential.......... 1.44 0.97 0.79 0.64 1.09
----------------------------------------------------------------------------------------------------------------
* Slope factor for all equipment: 0.77.
** Slope factor for two-stage equipment: 1.15. Slope factor for variable speed equipment: 1.07.
h. Translation of CAC/HP ECS Working Group Recommended HSPF Levels
Using Proposed Heating Load Line Equation Changes
Recommendation #9 of the CAC/HP ECS Working Group Term Sheet
included two sets of recommended national HSPF standard levels. The
Working Group based these levels on heating load line equation slope
factors of 1.02 and 1.30 to reflect the two factors primarily discussed
during the negotiations. The Working Group designated these levels as
``HSPF2'' to indicate that they are not equivalent to current HSPF
ratings. Table III.9 includes the Working Group's recommended HSPF
levels:
Table III.9--CAC/HP ECS Working Group Recommended HSPF Levels Based on
Previously Proposed Heating Load Line Equations
------------------------------------------------------------------------
Product class HSPF2-1.02 HSPF2-1.30
------------------------------------------------------------------------
Split-System Heat Pumps............. 7.8 7.1
Single-Package Heat Pumps........... 7.1 6.5
------------------------------------------------------------------------
As mentioned, the Working Group ultimately left the decision of the
appropriate heating load line equation factor up to DOE. The HSPF
levels recommended by the Working Group are based on different heating
load line equation factors than DOE is proposing in this SNOPR.
Consequently, DOE determined HSPF levels that are consistent with those
recommended by the Working Group but based on the 1.15 heating load
line equation factor DOE proposes in this notice. DOE does not have
access to all of the data or details of the methodology used by the
Working Group to derive the HSPF levels it recommended. In the absence
of this information, DOE used linear interpolation between the HSPF
values recommended by the Working Group using 1.02 and 1.30 to derive
the associated HSPF values using a heating load line equation factor of
1.15. DOE confirmed that linear interpolation provides good match to
directly calculated results using available heat pump performance data.
Specifically,
[[Page 58191]]
the maximum deviation for an interpolated value is 0.04 HSPF points for
a representative sample of heat pumps, and the average deviation is
0.005 HSPF points. Table III.10 includes the HSPF levels that are
consistent with the Working Group recommended HSPF levels, but based on
a 1.15 heating load line equation slope factor.
Table III.10--CAC/HP ECS Working Group Recommended HSPF Levels Based on
Currently Proposed Heating Load Line Equation
------------------------------------------------------------------------
Product class HSPF
------------------------------------------------------------------------
Split-System Heat Pumps...................................... 7.5
Single-Package Heat Pumps.................................... 6.8
------------------------------------------------------------------------
Issue 21: DOE requests comments on the adjusted values of minimum
HSPF based on the HSPF efficiency levels recommended by the CAC/HP ECS
Working Group.
i. Consideration of Inaccuracies Associated With Minimum-Speed
Extrapolation for Variable-Speed Heat Pumps
DOE discussed in the November 2015 SNOPR potential inaccuracy
associated with the use of test data conducted at minimum speed in 47
[deg]F and 62 [deg]F ambient temperature to estimate heat pump
performance below 47 [deg]F. 80 FR at 69322-3 (Nov. 9, 2015).
Specifically, for heat pumps that increase compressor speed as ambient
temperature drops below 47 [deg]F, the extrapolation of performance
based on the 47 [deg]F and 62 [deg]F minimum-speed tests over-estimates
efficiency. Because the bins in this temperature range have many hours
associated with them, the impact on HSPF of this inaccuracy can be
significant, particularly with the current test procedure, which uses a
0.77 heating load line equation slope factor. However, for the 1.3
slope factor proposed in the November 2015 SNOPR, DOE found that the
impact on HSPF for the available heat pump data was too small to
justify modifying the test procedure. The higher slope factor reduces
the impact of the issue because the higher heating load reduces the
weighting of the HSPF on minimum-speed performance. DOE indicated that,
because the higher slope factor alleviated the minimum-speed
inaccuracy, it did not propose any test procedure amendment to address
this issue, but that it might reconsider this possibility if a lower
heating load line equation slope factor were adopted. Id.
DOE proposed two potential approaches to resolve this minimum-speed
issue. The first would have involved approximation of minimum-speed
performance between 35 [deg]F and 47 [deg]F based on the intermediate-
speed frosting-operation test at 35 [deg]F and the minimum-speed test
at 47 [deg]F, and assuming that below 35 [deg]F the nominal minimum
speed is the same as the intermediate speed. This first approach would
not have required any additional testing. The second approach discussed
for resolving the issue was to require two additional tests, one
intermediate-speed test at 17 [deg]F and one minimum-speed frosting-
operation test at 35 [deg]F. DOE requested comment on which of these
approaches would be preferable. 80 FR at 69323 (Nov. 9, 2015). A
summary of the comments received is located in section III.C.3.d.
As discussed in this preamble, DOE is proposing in this SNOPR to
reduce the heating load line equation slope factor to 1.07 for
variable-speed heat pumps. At this level, the data currently available
to DOE suggests that the HSPF may be overestimated by as much as 16
percent as a result of the inaccuracy associated with the minimum-speed
extrapolation. Hence, DOE is also proposing revision to the estimation
of minimum-speed performance to reduce the impact of the error.
Consistent with stakeholder comments, DOE is proposing to adopt the
approach discussed in the November 2015 SNOPR that does not require
additional testing. Further, DOE proposes that the approach be used
only for heat pumps that vary the minimum speed when operating in
outdoor temperatures that are in a range for which the minimum-speed
performance factors into the HSPF calculation. For example, if the
rotational compressor operating speed for a heat pump operating at its
minimum speed remains constant down to 37 [deg]F and the HSPF
calculation considers minimum-speed operation only down to the 37
[deg]F temperature bin (this would occur if the calculated heating load
is equal to or greater than the intermediate-speed capacity for
temperature bins below 37 [deg]F), any rotational speed increase below
37 [deg]F would not require use of the alternative calculation. DOE
proposes adoption of a definition, ``minimum-speed-limiting variable-
speed heat pump,'' to refer to such heat pumps.
For the variable-speed heat pumps for which DOE's contractor
received data from AHRI during the 2015-2016 ASRAC Negotiations, use of
this approach would reduce average HSPF from 9.26 to 9.13, reducing the
VS/TS differential to 0.96, which is equivalent to the differential for
a 1.02 slope factor without considering any different treatment of
variable-speed heat pumps (see Table III-11). However, it is not clear
that all the heat pumps of the AHRI dataset would have required use of
the alternative calculation approach, so the actual reduction in the
average HSPF could be less.
DOE notes that it described another option for reducing the
minimum-speed inaccuracy in the November 2015 SNOPR, specifically
requiring additional tests to more thoroughly explore the heat pump's
performance for the range of different operating speeds and ambient
conditions. DOE could consider additional tests to improve accuracy
further. Potential additional tests would include an intermediate-speed
test at 17 [deg]F, and either minimum-speed frosting-condition tests
near 35 [deg]F or minimum-speed steady-state tests at 40 [deg]F or
above. The HSPF calculation could be adjusted to provide better
estimates of variable-speed heat pump performance over the range of
conditions considered in the calculation based on one or more of these
tests.
DOE also proposes that certification reports indicate as part of
non-public data whether the alternative calculation method was used to
determine the heat pump's rating.
Issue 22: DOE requests comment on its proposal to require use of an
alternative HSPF rating approach (for heat pumps that raise minimum
compressor speed in ambient temperatures that impact the HSPF
calculation) that estimates minimum-speed performance (a) between 35
[deg]F and 47 [deg]F using the intermediate-speed frosting-operation
test at 35 [deg]F and the minimum-speed test at 47 [deg]F, and (b)
below 35 [deg]F assuming that minimum-speed and intermediate-speed
performance are the same. In addition, DOE requests comment on
including in certification reports for variable-speed heat pumps
whether this alternative approach was used to determine the rating.
Finally, DOE requests comment on whether any of the additional tests
that could be used to further improve the accuracy of variable-speed
heat pump performance estimates should be required in the test
procedure.
4. Revised Heating Mode Test Procedure for Units Equipped With Variable
Speed Compressors
In the November 2015 SNOPR, DOE revisited the heating season
ratings procedure for variable speed heat pumps found in section 4.2.4
of Appendix M of 10 CFR part 430 subpart B. 80 FR at 69322 (Nov. 9,
2015).
DOE proposed as part of Appendix M1 that for variable speed units
that
[[Page 58192]]
limit the maximum speed operation below 17 [deg]F and have a low cutoff
temperature (temperature below which the unit will not operate in heat
pump mode) less than 12 [deg]F, the manufacturer could choose to
calculate the maximum heating capacity and the corresponding energy
usage for ambient temperatures less than 17 [deg]F based on two maximum
speed tests at: (1) 17 [deg]F outdoor temperature, and (2) 2 [deg]F
outdoor temperature or at the low cutoff temperature, whichever is
higher.\25\ The proposal would have allowed manufacturers to choose to
conduct one additional steady state test, at maximum compressor speed
and at a low temperature of 2 [deg]F or at a low cutoff temperature,
whichever is higher. 80 FR at 69323 (Nov. 9, 2015).
---------------------------------------------------------------------------
\25\ In the November 2015 SNOPR, DOE proposed that in the case
that the low cutoff temperature is higher than 12 [deg]F, the
manufacturer would not be allowed to utilize this option for
calculation of the maximum heating load capacity.
---------------------------------------------------------------------------
Testing done by ORNL found that the unit efficiency at maximum
speed below 17[emsp14][deg]F is slightly higher than the extrapolated
values in the current test procedure, and this proposed option would
provide a more accurate prediction of heat pump low-ambient
performance, not only for those units that limit maximum speed
operation below 17[emsp14][deg]F, but also for those that do not.\26\
DOE therefore proposed to revise Appendix M1 such that, for variable
speed units that do not limit maximum speed operation below
17[emsp14][deg]F, manufacturers would also have the option to use this
revised method if it is more representative of low ambient performance.
80 FR at 69323 (Nov. 9, 2015).
---------------------------------------------------------------------------
\26\ Rice et al. (2015) Review of Test Procedure for Determining
HSPFs of Residential Variable-Speed Heat pumps. (Docket No. EERE-
2009-BT-TP-0004-0047).
---------------------------------------------------------------------------
DOE developed the proposal based on review of the results of a
limited number of tests. DOE requested test results and other data to
show whether the impact on HSPF of the proposal is similar for other
variable speed heat pumps, and also requested comment on the additional
test burden of the proposed modification. 80 FR at 69323 (Nov. 9,
2015).
Several stakeholders provided comments in response to these
requests for data and comments.
JCI supported the proposal on the condition that the tests be made
optional, but at a higher temperature (e.g., 10 degrees) so that more
test labs can perform the test. (CAC TP: JCI, No. 66 at p. 22)
Lennox and ADP expressed concerns over the difficulty of testing at
2[emsp14][deg]F for many labs, commenting that the test would greatly
increase the burden on manufacturers as it would greatly increase the
test time to achieve the 2[emsp14][deg]F test point, possibly require
expensive hardware upgrades for labs, or force manufacturers to use
outside labs. (CAC TP: Lennox, No. 61 at p. 20; ADP, No. 59 at p. 13)
Rheem commented that the proposed 2[emsp14][deg]F outdoor
temperature introduces testing variability, and that the very low test
temperature introduces a significant test burden because it is rare for
manufacturers or independent labs to have such facilities. Rheem
commented that there is no justification that the resulting HSPF
results will more closely match the resulting energy costs to
consumers. Major capital investment by manufacturers and independent-
labs would be required to add this capability. (CAC TP: Rheem, No. 69
at p. 17)
Unico commented that most heat pumps are not able to be tested
below 17[emsp14][deg]F and that most test laboratories cannot test
below 17[emsp14][deg]F. Nevertheless, they also mentioned (a) public
interest in heat pumps that operate at significantly lower temperatures
and (b) manufacturers that are publishing data and promoting such cold
climate heat pumps. Unico expressed support for a separate heat pump
test standard for cold-weather heat pumps, indicating that such a test
standard would require testing at 2[emsp14][deg]F. (CAC TP: Unico, No.
63 at p. 13)
UTC/Carrier commented that the test point at 2[emsp14][deg]F
outdoor temperature is challenging for most test facilities (if it is
possible at all). (CAC TP: UTC/Carrier, No. 62 at p. 22)
The California IOUs and ACEEE, NRDC, and ASAP commented that in
response to industry's concerns over testing at 2[emsp14][deg]F, they
recommend that variable speed heat pumps be tested at 5[emsp14][deg]F,
in addition to the 17[emsp14][deg]F cold temperature point. ACEEE,
NRDC, and ASAP commented that requiring the 5[emsp14][deg]F test seems
to be a reasonable way to differentiate excellent cold-temperature
performance, which is critical for customer acceptance nationally, and
for mitigating winter peaks for utilities. The California IOUs noted
that the European standard requires testing at 5[emsp14][deg]F and that
manufacturers participate in the global market and Europe, so that they
must test at 5[emsp14][deg]F. (CAC TP: California IOUs, No. 67 at p. 7;
ACEEE, NRDC, and ASAP, No. 72 at p. 5)
NEEA and NPCC commented that they do not believe that the current
test procedure for variable speed systems in any way delivers annual
energy use or efficiency ratings that are reasonably reflective of an
average use cycle. (CAC TP: NEEA and NPCC, No. 64 at p. 9)
The possible adoption of a very-low-temperature test for rating of
variable speed heat pumps was also discussed during the CAC/HP ECS
Working Group meetings, ultimately leading to Recommendation #5 in the
Term Sheet, that a 5[emsp14][deg]F ambient temperature optional test be
adopted for variable speed heat pumps. (CAC ECS: ASRAC Term Sheet, No.
76 at p. 3) Given the consensus among Working Group members regarding
this recommendation, DOE believes that the concerns expressed by the
initial comments about this optional test would be resolved by adopting
a 5[emsp14][deg]F ambient temperature for the test rather than the
2[emsp14][deg]F initially proposed.
In addition, DOE discussed in the November 2015 SNOPR the
possibility of making an adjustment to the test procedure to address
potential accuracy issues associated with estimation of minimum-speed
heat pump performance for temperatures below 47[emsp14][deg]F based on
extrapolation of the results of tests conducted in 47[emsp14][deg]F and
62[emsp14][deg]F ambient temperatures. Specifically, testing by ORNL
indicated that the HSPF may be over-predicted for heat pumps that do
not allow use of the same minimum speed for ambient temperatures below
47[emsp14][deg]F. 80 FR 69322-3 (Nov. 9, 2015). However, DOE did not
propose to make this change in the November 2015 SNOPR, explaining that
the modification of the heating load line equation would sufficiently
alleviate the potential inaccuracy, making adjustment to the test
procedure unnecessary. However, DOE did request comment on preferences
for approaches to modification to the test procedure in case the
modified heating load line equation was not adopted, describing
approaches that would involve an additional test and an approach that
would not require additional testing. Id. This issue and DOE's proposal
to resolve it is discussed in greater detail in section III.C.3.i.
The revised variable speed heat pump test procedure proposed in
this notice would include the following changes in Appendix M1.
If the optional 5[emsp14][deg]F full-speed test (to be
designated H42) is conducted, full-speed performance for
ambient temperatures between 5[emsp14][deg]F and 17[emsp14][deg]F would
be calculated using interpolation between full-speed test measurements
conducted at these two temperatures, rather than the current approach,
which uses extrapolation of performance measured at 17[emsp14][deg]F
and 47[emsp14][deg]F ambient temperatures. For all heat pumps for which
the 5[emsp14][deg]F full-speed test is not
[[Page 58193]]
conducted, the extrapolation approach would still be used to represent
performance for all ambient temperatures below 17[emsp14][deg]F.
A target wet bulb temperature of 3.5[emsp14][deg]F for the
optional 5[emsp14][deg]F test.
If the optional 5[emsp14][deg]F full-speed test is
conducted, performance for ambient temperatures below 5[emsp14][deg]F
would be calculated using extrapolation below 5[emsp14][deg]F using the
same slopes (capacity vs. temperature and power input vs. temperature)
as determined for the heat pump between 17[emsp14][deg]F and
47[emsp14][deg]F. Specifically, the extrapolation would be based on the
17[emsp14][deg]F-to-47[emsp14][deg]F slope rather than the
5[emsp14][deg]F-to-17[emsp14][deg]F slope. If the 47[emsp14][deg]F
full-speed test is conducted at a different speed than the
17[emsp14][deg]F full-speed test, the extrapolation would be based on
the standardized slope discussed in section III.B.7.
Manufacturers would have to indicate in certification
reports whether the 5[emsp14][deg]F full-speed test was conducted.
As proposed for Appendix M and discussed in section
III.B.7, a 47[emsp14][deg]F full-speed test, designated the
H1N test, would be used to represent the heating capacity.
However, for Appendix M1, this test would be conducted at the maximum
speed at which the system controls would operate the compressor in
normal operation in a 47[emsp14][deg]F ambient temperature.
If the heat pump limits the use of the minimum speed
(measured in terms of RPM or power input frequency) of the heat pump
when operating at ambient temperatures below 47[emsp14][deg]F (i.e.
does not allow use of speeds as low as the minimum speed used at
47[emsp14][deg]F for any temperature below 47[emsp14][deg]F), a
modified calculation would be used to determine minimum-speed
performance below 47[emsp14][deg]F.
Development of these proposals and decisions regarding their
details is explained further below (except for the last proposal, which
is discussed in section III.C.3.i).
For heat pumps using the 5[emsp14][deg]F test, the CAC/HP ECS
Working Group Term Sheet recommended use of interpolation to calculate
heat pump performance in the temperature range from 5[emsp14][deg]F to
17[emsp14][deg]F based on the test results for the 5[emsp14][deg]F and
17[emsp14][deg]F tests (CAC ECS: ASRAC Term Sheet, No. 76 at p. 3,
Recommendation #5) DOE considered what approach to use for calculation
of heat pump performance below 5[emsp14][deg]F, with the understanding
that extrapolation of the 5[emsp14][deg]F-to-17[emsp14][deg]F trend
below 5[emsp14][deg]F is not likely to be accurate because full-speed
operation could be very different at 5[emsp14][deg]F than it is at
17[emsp14][deg]F. Although the November 2015 SNOPR primarily addressed
cases where the compressor speed could be lower at the lower
temperature (see, e.g. 80 FR at 69323 (Nov. 9, 2015)), the comments
focus more on the possibility of higher speed at lower temperature. In
any case, as indicated in this preamble, DOE does not believe such
extrapolation is appropriate when the compressor speeds may be very
different. DOE considered different approaches to calculate the
performance below 5[emsp14][deg]F and evaluated some of them using data
obtained from the NEEP cold climate heat pump database.\27\ Many of the
heat pumps in the database have performance data for both
5[emsp14][deg]F and for a lower ambient temperature. DOE evaluated for
each such heat pump of the database how closely the performance at the
lower ambient temperature could be predicted using the other available
performance data. DOE concluded that a good approach is to apply the
17[emsp14][deg]F-to-47[emsp14][deg]F slope below 5[emsp14][deg]F, for
both capacity and power input. Using this approach, the lower-
temperature capacity and power input were predicted within 10 percent
for at least two thirds of the evaluated heat pumps.\28\ DOE considers
this to be acceptable accuracy for HSPF calculations, considering that
the annual hours with temperature lower than 5[emsp14][deg]F are
limited, representing roughly one percent of heating season hours in
Region IV. Hence, DOE has proposed an approach for extrapolation of
heat pump performance for temperatures below 5[emsp14][deg]F based on
the slopes of the capacity and power input levels between
17[emsp14][deg]F and 47[emsp14][deg]F.
---------------------------------------------------------------------------
\27\ http://www.neep.org/initiatives/high-efficiency-products/emerging-technologies/ashp/cold-climate-air-source-heat-pump.
\28\ In contrast, if extrapolation of performance based on the 5
[deg]F and 17 [deg]F tests was used below 5 [deg]F, the capacity
would be within the 10% tolerance for none of the heat pumps, and
the power input would be within 10% for six percent of the analyzed
heat pumps.
---------------------------------------------------------------------------
Issue 23: DOE requests comment on the proposals for evaluation of
heat pump capacity and power input as a function of ambient temperature
based on test measurements, both for cases where a 5[emsp14][deg]F test
is conducted and where it isn't.
DOE chose a target wet bulb temperature for the 5[emsp14][deg]F
test equal to 3.5[emsp14][deg]F, corresponding to roughly 60 percent
relative humidity which is consistent with the range of relative
humidity of the other low temperature heating mode tests.
Issue 24: DOE requests comment on the target wet bulb temperature
for the 5[emsp14][deg]F test.
Issue 25: DOE requests general comments regarding its proposal to
adopt an optional 5[emsp14][deg]F test and regarding any other details
of the related amendments proposed for calculation of HSPF.
As discussed in this preamble, DOE has proposed changing the
ambient temperature requirement for the very-low-temperature heating
mode test for variable-speed heat pumps from 2[emsp14][deg]F to
5[emsp14][deg]F. DOE notes that it proposed a 2[emsp14][deg]F test for
triple-capacity northern heat pumps in the June 2010 NOPR which was
established as part of the test procedure in the June 2016 final rule.
81 FR at 37020 (June 8, 2016).
Issue 26: DOE requests comments on whether the very-low-temperature
heating mode test for triple-capacity northern heat pumps should be
changed to a 5[emsp14][deg]F test for consistency with the proposed
5[emsp14][deg]F variable-speed test.
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Order 12866
The Office of Management and Budget (OMB) has determined that test
procedure rulemakings do not constitute ``significant regulatory
actions'' under section 3(f) of Executive Order 12866, Regulatory
Planning and Review, 58 FR 51735 (Oct. 4, 1993). Accordingly, this
action was not subject to review under the Executive Order by the
Office of Information and Regulatory Affairs (OIRA) in the Office of
Management and Budget.
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires
preparation of an initial regulatory flexibility analysis (IFRA) for
any rule that by law must be proposed for public comment, unless the
agency certifies that the rule, if promulgated, will not have a
significant economic impact on a substantial number of small entities.
As required by Executive Order 13272, ``Proper Consideration of Small
Entities in Agency Rulemaking,'' 67 FR 53461 (August 16, 2002), DOE
published procedures and policies on February 19, 2003, to ensure that
the potential impacts of its rules on small entities are properly
considered during the DOE rulemaking process. 68 FR 7990. DOE has made
its procedures and policies available on the Office of the General
Counsel's Web site: http://energy.gov/gc/office-general-counsel.
DOE reviewed this proposed rule, which would amend the test
procedure for CAC/HP, under the provisions of the Regulatory
Flexibility Act and the procedures and policies published on February
19, 2003. DOE has estimated
[[Page 58194]]
the impacts of the test procedure changes on small business
manufacturers.
For the purpose of the regulatory flexibility analysis for this
rule, the DOE adopts the Small Business Administration (SBA) definition
of a small entity within this industry as a manufacturing enterprise
with 1,250 employees or fewer. DOE used the small business size
standards published by the SBA to determine whether any small entities
would be required to comply with this rule. The size standards are
codified at 13 CFR part 121. The standards are listed by North American
Industry Classification System (NAICS) code and industry description
and are available at https://www.sba.gov/sites/default/files/files/Size_Standards_Table.pdf.
CAC/HP manufacturing is classified under NAICS 333415, ``Air
Conditioning and Warm Air Heating Equipment and Commercial and
Industrial Refrigeration Equipment Manufacturing.'' 70 FR 12395 (March
11, 2005). DOE reviewed publicly available data and contacted various
companies on its complete list of manufacturers to determine whether
they met the SBA's definition of a small business manufacturer. As a
result of this review, DOE identified 22 manufacturers of CAC/HP that
would be considered domestic small businesses with a total of less than
3 percent of the market sales.
Issue 27: DOE seeks comment on its estimate of the number of small
entities that may be impacted by the proposed test procedure.
Potential impacts of the proposed test procedure on all
manufacturers, including small businesses, come from impacts associated
with the cost of proposed additional testing. DOE expects that many of
the provisions proposed in this notice will result in no increase to
test burden. DOE's proposals to use new heating load line equation
provisions to calculate HSPF for heat pumps, new default values for
indoor fan power consumption, and a new interpolation approach for COP
of variable speed heat pumps are changes to calculations and do not
require any additional time or investment from manufacturers.
Similarly, DOE's proposal to require certification of the time delay
used when testing coil-only units does not affect testing. DOE's
proposal to test at new minimum external static pressure conditions
would require manufacturers to test at different, but not additional
test points using the same equipment and methodologies required by the
current test procedure. DOE's proposal for single-package units to make
the official test the test that does not include the secondary outdoor
air enthalpy method measurement also does not require any additional
testing. Similarly, DOE's proposal to include an optional test at
5[emsp14][deg]F for variable speed heat pumps does not require
manufacturers to do any additional testing. Other proposed provisions
may increase test burden. DOE anticipates that its proposed changes to
provisions for mini-split refrigerant pressure lines may cause labs and
manufacturers to relocate pressure transducers or in a worst case
scenario, build a separate satellite test instrumentation console for
pressure measurements closer to the test samples. DOE estimates that
building such a satellite console would constitute a one-time cost on
the order of $1,000 per test room. DOE's proposal to modify the off
mode test for units with self-regulated crankcase heaters could result
in more significant increases to test burden, but for a small number of
models. DOE estimates that the new provisions could add 8 hours per
test for units with self-regulated crankcase heaters and an additional
8 hours for those units with self-regulated crankcase heaters that also
have a compressor sound blanket. Sound blankets are premium features.
DOE estimates that less than 25 percent of all units have self-
regulated crankcase heaters and less than 5 percent have self-regulated
crankcase heaters and sound blankets. DOE estimates the additional cost
of testing to be $250 for units with self-regulating crankcase heaters
and $500 for units with self-regulating crankcase heaters and sound
blankets. DOE also estimates that testing of basic models may not have
to be updated more than once every five years, and therefore the
average incremental burden of testing one basic model may be one-fifth
of these values when the cost is spread over several years.
DOE is proposing labeling requirements for the indoor and outdoor
units of mobile home blower coil and coil-only systems and is also
proposing that manufacturers include a specific designation in the
installation instructions for these units. For further discussion of
the proposed labeling requirements, see section III.C.1. As discussed
in that section, DOE expects the additional cost to manufacturers
associated with meeting the labeling requirement would be marginal as
compared to the total production cost. The overall impact would be
small.
As discussed in this preamble, DOE identified 22 domestic small
business manufacturers of CAC/HP. Of these, only OUMs that operate
their own manufacturing facilities (i.e., are not private labelers
selling only models manufactured by other entities) and OUM importing
private labelers would be subject to the additional requirements for
testing required by this proposed rule. DOE identified 12 such small
businesses but was able to estimate the number of basic models
associated only with nine of these.
DOE requires that only one combination associated with any given
outdoor unit be laboratory tested. 10 CFR 429.16(b). The majority of
CAC/HP offered by a manufacturer are split-system combinations that are
not required to be laboratory tested but can be certified using an AEDM
that does not require DOE testing of these units. DOE reviewed
available data for the nine small businesses to estimate the
incremental testing cost burden those firms might experience due to the
revised test procedure. These manufacturers had an average of 35 models
requiring testing. DOE determined the numbers of models using the AHRI
Directory of Certified Product Performance, www.ahridirectory.org/ahridirectory/pages/home.aspx. As discussed, DOE estimates that less
than 25 percent of models have self-regulating crankcase heaters and
less than 5 percent have self-regulating crankcase heaters with
blankets. Applying these estimates to the average 35 models for each
small manufacturer results in an estimated two models with $500 per
model in additional test costs and nine models with $250 per model in
additional test costs as a result of the proposed changes. The
additional testing cost for final certification of these models was
therefore estimated at $3,250. Meanwhile, these certifications would be
expected to last the CAC/HP life, estimated to be at least five years
based on the time frame established in EPCA for DOE review of central
air conditioner efficiency standards. Hence, average annual additional
costs for these small business manufacturers to perform the tests as
revised by the proposal is $650.
DOE does not expect ICMs to incur any additional burden as a result
of the proposed changes because the changes for which DOE estimates
there will be increased burden do not apply to ICMs. Only outdoor units
include self-regulating crankcase heaters with or without blankets, and
DOE assumes that ICM manufacturers do not produce indoor units that
have components with off mode power consumption. Consequently, ICMs
would be able to use the off mode power measurements acquired and
certified by OUMs to meet
[[Page 58195]]
the test procedure requirements for off mode. Regarding the proposed
changes for mini-split refrigerant lines, DOE is not aware of any ICMs
that maintain in-house test facilities. Consequently, the one-time cost
associated with the proposed changes for mini-split refrigerant lines
would not be incurred by the ICM. DOE also anticipates that the one-
time cost is low enough that the per-test cost charged by independent
labs that provide testing services to ICMs would not increase as a
result of this proposed change.
Issue 28: DOE seeks comment on its estimate of the impact of the
proposed test procedure amendments on small entities.
C. Review Under the Paperwork Reduction Act of 1995
Manufacturers of central air conditioners and heat pumps must
certify to DOE that their products comply with any applicable energy
conservation standards. In certifying compliance, manufacturers must
test their products according to the DOE test procedures for central
air conditioners and heat pumps, including any amendments adopted for
those test procedures. DOE has established regulations for the
certification and recordkeeping requirements for all covered consumer
products and commercial equipment, including central air conditioners
and heat pumps. 76 FR 12422 (March 7, 2011); 80 FR 5099 (Jan. 30,
2015). The collection-of-information requirement for the certification
and recordkeeping is subject to review and approval by OMB under the
Paperwork Reduction Act (PRA). This requirement has been approved by
OMB under OMB control number 1910-1400. Public reporting burden for the
certification is estimated to average 30 hours per response, including
the time for reviewing instructions, searching existing data sources,
gathering and maintaining the data needed, and completing and reviewing
the collection of information.
Notwithstanding any other provision of the law, no person is
required to respond to, nor shall any person be subject to a penalty
for failure to comply with, a collection of information subject to the
requirements of the PRA, unless that collection of information displays
a currently valid OMB Control Number.
D. Review Under the National Environmental Policy Act of 1969
In this proposed rule, DOE proposes test procedure amendments that
it expects will be used to develop and implement future energy
conservation standards for central air conditioners and heat pumps. DOE
has determined that this rule falls into a class of actions that are
categorically excluded from review under the National Environmental
Policy Act of 1969 (42 U.S.C. 4321 et seq.) and DOE's implementing
regulations at 10 CFR part 1021. Specifically, this proposed rule would
amend the existing test procedures without affecting the amount,
quality or distribution of energy usage, and, therefore, would not
result in any environmental impacts. Thus, this rulemaking is covered
by Categorical Exclusion A5 under 10 CFR part 1021, subpart D, which
applies to any rulemaking that interprets or amends an existing rule
without changing the environmental effect of that rule. Accordingly,
neither an environmental assessment nor an environmental impact
statement is required.
DOE's CX determination for this proposed rule is available at
http://energy.gov/nepa/categorical-exclusion-cx-determinations-cx.
E. Review Under Executive Order 13132
Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4, 1999)
imposes certain requirements on agencies formulating and implementing
policies or regulations that preempt State law or that have Federalism
implications. The Executive Order requires agencies to examine the
constitutional and statutory authority supporting any action that would
limit the policymaking discretion of the States and to carefully assess
the necessity for such actions. The Executive Order also requires
agencies to have an accountable process to ensure meaningful and timely
input by State and local officials in the development of regulatory
policies that have Federalism implications. On March 14, 2000, DOE
published a statement of policy describing the intergovernmental
consultation process it will follow in the development of such
regulations. 65 FR 13735. DOE has examined this proposed rule and has
determined that it would not have a substantial direct effect on the
States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government. EPCA governs and prescribes Federal
preemption of State regulations as to energy conservation for the
products that are the subject of this proposed rule. States can
petition DOE for exemption from such preemption to the extent, and
based on criteria, set forth in EPCA. (42 U.S.C. 6297(d)) No further
action is required by Executive Order 13132.
F. Review Under Executive Order 12988
Regarding the review of existing regulations and the promulgation
of new regulations, section 3(a) of Executive Order 12988, ``Civil
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal
agencies the general duty to adhere to the following requirements: (1)
Eliminate drafting errors and ambiguity; (2) write regulations to
minimize litigation; (3) provide a clear legal standard for affected
conduct rather than a general standard; and (4) promote simplification
and burden reduction. Section 3(b) of Executive Order 12988
specifically requires that Executive agencies make every reasonable
effort to ensure that the regulation: (1) Clearly specifies the
preemptive effect, if any; (2) clearly specifies any effect on existing
Federal law or regulation; (3) provides a clear legal standard for
affected conduct while promoting simplification and burden reduction;
(4) specifies the retroactive effect, if any; (5) adequately defines
key terms; and (6) addresses other important issues affecting clarity
and general draftsmanship under any guidelines issued by the Attorney
General. Section 3(c) of Executive Order 12988 requires Executive
agencies to review regulations in light of applicable standards in
sections 3(a) and 3(b) to determine whether they are met or it is
unreasonable to meet one or more of them. DOE has completed the
required review and determined that, to the extent permitted by law,
the proposed rule meets the relevant standards of Executive Order
12988.
G. Review Under the Unfunded Mandates Reform Act of 1995
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA)
requires each Federal agency to assess the effects of Federal
regulatory actions on State, local, and Tribal governments and the
private sector. Public Law 104-4, sec. 201 (codified at 2 U.S.C. 1531).
For a proposed regulatory action likely to result in a rule that may
cause the expenditure by State, local, and Tribal governments, in the
aggregate, or by the private sector of $100 million or more in any one
year (adjusted annually for inflation), section 202 of UMRA requires a
Federal agency to publish a written statement that estimates the
resulting costs, benefits, and other effects on the national economy.
(2 U.S.C. 1532(a), (b)) The UMRA also requires a Federal agency to
develop an effective process to permit timely input by elected officers
of State, local, and Tribal governments on a proposed ``significant
intergovernmental mandate,'' and
[[Page 58196]]
requires an agency plan for giving notice and opportunity for timely
input to potentially affected small governments before establishing any
requirements that might significantly or uniquely affect small
governments. On March 18, 1997, DOE published a statement of policy on
its process for intergovernmental consultation under UMRA. 62 FR 12820;
also available at http://energy.gov/gc/office-general-counsel. DOE
examined this proposed rule according to UMRA and its statement of
policy and determined that the rule contains neither an
intergovernmental mandate, nor a mandate that may result in the
expenditure of $100 million or more in any year, so these requirements
do not apply.
H. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family
Policymaking Assessment for any rule that may affect family well-being.
This rule would not have any impact on the autonomy or integrity of the
family as an institution. Accordingly, DOE has concluded that it is not
necessary to prepare a Family Policymaking Assessment.
I. Review Under Executive Order 12630
DOE has determined, under Executive Order 12630, ``Governmental
Actions and Interference with Constitutionally Protected Property
Rights'' 53 FR 8859 (March 18, 1988), that this regulation would not
result in any takings that might require compensation under the Fifth
Amendment to the U.S. Constitution.
J. Review Under Treasury and General Government Appropriations Act,
2001
Section 515 of the Treasury and General Government Appropriations
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most
disseminations of information to the public under guidelines
established by each agency pursuant to general guidelines issued by
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). DOE has
reviewed this proposed rule under the OMB and DOE guidelines and has
concluded that it is consistent with applicable policies in those
guidelines.
K. Review Under Executive Order 13211
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355
(May 22, 2001), requires Federal agencies to prepare and submit to OMB,
a Statement of Energy Effects for any proposed significant energy
action. A ``significant energy action'' is defined as any action by an
agency that promulgated or is expected to lead to promulgation of a
final rule, and that: (1) Is a significant regulatory action under
Executive Order 12866, or any successor order; and (2) is likely to
have a significant adverse effect on the supply, distribution, or use
of energy; or (3) is designated by the Administrator of OIRA as a
significant energy action. For any proposed significant energy action,
the agency must give a detailed statement of any adverse effects on
energy supply, distribution, or use should the proposal be implemented,
and of reasonable alternatives to the action and their expected
benefits on energy supply, distribution, and use.
The proposed regulatory action to amend the test procedure for
measuring the energy efficiency of central air conditioners and heat
pumps is not a significant regulatory action under Executive Order
12866. Moreover, it would not have a significant adverse effect on the
supply, distribution, or use of energy, nor has it been designated as a
significant energy action by the Administrator of OIRA. Therefore, it
is not a significant energy action, and, accordingly, DOE has not
prepared a Statement of Energy Effects.
L. Review Under Section 32 of the Federal Energy Administration Act of
1974
Under section 301 of the Department of Energy Organization Act
(Pub. L. 95-91; 42 U.S.C. 7101), DOE must comply with section 32 of the
Federal Energy Administration Act of 1974, as amended by the Federal
Energy Administration Authorization Act of 1977. (15 U.S.C. 788; FEAA)
Section 32 essentially provides in relevant part that, where a proposed
rule authorizes or requires use of commercial standards, the notice of
proposed rulemaking must inform the public of the use and background of
such standards. In addition, section 32(c) requires DOE to consult with
the Attorney General and the Chairman of the Federal Trade Commission
(FTC) concerning the impact of the commercial or industry standards on
competition.
The proposed rule incorporates testing methods contained in the
following commercial standards: AHRI 210/240-2008 with Addendum 1 and
2, Performance Rating of Unitary Air Conditioning & Air-Source Heat
Pump Equipment; and ANSI/AHRI 1230-2010 with Addendum 2, Performance
Rating of Variable Refrigerant Flow Multi-Split Air Conditioning and
Heat Pump Equipment. While the proposed test procedure is not
exclusively based on AHRI 210/240-2008 or ANSI/AHRI 1230-2010, one
component of the test procedure, namely test setup requirements, adopts
language from AHRI 210/240-2008 without amendment; and another
component of the test procedure, namely test setup and test performance
requirements for multi-split systems, adopts language from ANSI/AHRI
1230-2010 without amendment. The Department has evaluated these
standards and is unable to conclude whether they fully comply with the
requirements of section 32(b) of the FEAA, (i.e., that they were
developed in a manner that fully provides for public participation,
comment, and review). DOE will consult with the Attorney General and
the Chairman of the FTC concerning the impact of these test procedures
on competition, prior to prescribing a final rule.
M. Description of Materials Incorporated by Reference
In this SNOPR, DOE proposes to incorporate by reference (IBR) into
the proposed Appendix M1 to subpart B of part 430 specific sections,
figures, and tables of several test standards published by AHRI,
ASHRAE, and AMCA that are already incorporated by reference into
Appendix M to subpart B of part 430: ANSI/AHRI 210/240-2008 with
Addenda 1 and 2, titled ``Performance Rating of Unitary Air-
Conditioning & Air-Source Heat Pump Equipment;'' ANSI/AHRI 1230-2010
with Addendum 2, titled ``Performance Rating of Variable Refrigerant
Flow (VRF) Multi-Split Air-Conditioning and Heat Pump Equipment;''
ASHRAE 23.1-2010, titled ``Methods of Testing for Rating the
Performance of Positive Displacement Refrigerant Compressors and
Condensing Units that Operate at Subcritical Temperatures of the
Refrigerant;'' ASHRAE Standard 37-2009, titled ``Methods of Testing for
Rating Electrically Driven Unitary Air-Conditioning and Heat Pump
Equipment;'' ASHRAE 41.1-2013, titled ``Standard Method for Temperature
Measurement;'' ASHRAE 41.2-1987 (RA 1992), titled ``Standard Methods
for Laboratory Airflow Measurement;'' ASHRAE 41.6-2014, titled
``Standard Method for Humidity Measurement;''
[[Page 58197]]
ASHRAE 41.9-2011, titled ``Standard Methods for Volatile-Refrigerant
Mass Flow Measurements Using Calorimeters;'' ASHRAE 116-2010, titled
``Methods of Testing for Rating Seasonal Efficiency of Unitary Air
Conditioners and Heat Pumps;'' and AMCA 210-2007, titled ``Laboratory
Methods of Testing Fans for Certified Aerodynamic Performance Rating.''
ANSI/AHRI 210/240-2008 is an industry accepted test procedure that
measures the cooling and heating performance of central air
conditioners and heat pumps and is applicable to products sold in North
America. The test procedure proposed in this SNOPR references various
sections of ANSI/AHRI 210/240-2008 that address test setup, test
conditions, and rating requirements. ANSI/AHRI 210/240-2008 is readily
available on AHRI's Web site at http://www.ahrinet.org/site/686/Standards/HVACR-Industry-Standards/Search-Standards.
ANSI/AHRI 1230-2010 is an industry accepted test procedure that
measures the cooling and heating performance of variable refrigerant
flow (VRF) multi-split air conditioners and heat pumps and is
applicable to products sold in North America. The test procedure
proposed in this SNOPR for VRF multi-split systems references various
sections of ANSI/AHRI 1230-2010 that address test setup, test
conditions, and rating requirements. ANSI/AHRI 1230-2010 is readily
available on AHRI's Web site at http://www.ahrinet.org/site/686/Standards/HVACR-Industry-Standards/Search-Standards.
ASHRAE 23.1-2010 is an industry accepted test procedure for rating
the thermodynamic performance of positive displacement refrigerant
compressors and condensing units that operate at subcritical
temperatures. The test procedure proposed in this SNOPR references
sections of ASHRAE 23.1-2010 that address requirements, instruments,
methods of testing, and testing procedure specific to compressor
calibration. ASHRAE 23.1-2010 can be purchased from ASHRAE's Web site
at https://www.ashrae.org/resources-publications.
ASHRAE Standard 37-2009 is an industry accepted standard that
provides test methods for determining the cooling capacity of unitary
air conditioning equipment and the cooling or heating capacities, or
both, of unitary heat pump equipment. The test procedure proposed in
this SNOPR references various sections of ASHRAE Standard 37-2009 that
address test conditions and test procedures. ASHRAE Standard 37-2009
can be purchased from ASHRAE's Web site at https://www.ashrae.org/resources-publications.
ASHRAE 41.1-2013 is an industry accepted method for measuring
temperature in testing heating, refrigerating, and air conditioning
equipment. The test procedure proposed in this SNOPR references
sections of ASHRAE 41.1-2013 that address requirements, instruments,
and methods for measuring temperature. ASHRAE 41.1-2013 can be
purchased from ASHRAE's Web site at https://www.ashrae.org/resources-publications.
ASHRAE 41.2-1987 (RA 1992) is an industry accepted test method for
measuring airflow. The test procedure proposed in this SNOPR references
sections of ASHRAE 41.2-1987 (RA 1992) that address test setup and test
methods. ASHRAE 41.2-1987 (RA 1992) can be purchased from ASHRAE's Web
site at https://www.ashrae.org/resources-publications.
ASHRAE 41.6-2014 is an industry accepted test method for measuring
humidity of moist air. The test procedure proposed in this SNOPR
references sections of ASHRAE 41.6-2014 that address requirements,
instruments, and methods for measuring humidity. ASHRAE 41.6-2014 can
be purchased from ASHRAE's Web site at https://www.ashrae.org/resources-publications.
ASHRAE 41.9-2011 is an industry accepted standard that provides
recommended practices for measuring the mass flow rate of volatile
refrigerants using calorimeters. The test procedure proposed in this
SNOPR references sections of ASHRAE 41.9-2011 that address
requirements, instruments, and methods for measuring refrigerant flow
during compressor calibration. ASHRAE 41.9-2011 can be purchased from
ASHRAE's Web site at https://www.ashrae.org/resources-publications.
ANSI/ASHRAE Standard 116-2010 is an industry accepted standard that
provides test methods and calculation procedures for determining the
capacities and cooling seasonal efficiency ratios for unitary air-
conditioning, and heat pump equipment and heating seasonal performance
factors for heat pump equipment. The test procedure proposed in this
SNOPR references various sections of ANSI/ASHRAE 116-2010 that
addresses test methods and calculations. ANSI/ASHRAE Standard 116-2010
can be purchased from ASHRAE's Web site at https://www.ashrae.org/resources-publications.
AMCA 210-2007 is an industry accepted standard that establishes
uniform test methods for a laboratory test of a fan or other air moving
device to determine its aerodynamic performance in terms of airflow
rate, pressure developed, power consumption, air density, speed of
rotation, and efficiency for rating or guarantee purposes. The test
procedure in this SNOPR references various sections of AMCA 210-2007
that address test conditions. AMCA 210-2007 can be purchased from
AMCA's Web site at http://www.amca.org/store/index.php.
V. Public Participation
A. Attendance at the Public Meeting
The time, date, and location of the public meeting are listed in
the DATES and ADDRESSES sections at the beginning of this document. If
you plan to attend the public meeting, please notify the Appliance and
Equipment Standards staff at (202) 586-6636 or
[email protected].
Please note that foreign nationals participating in the public
meeting are subject to advance security screening procedures which
require advance notice prior to attendance at the public meeting. If a
foreign national wishes to participate in the public meeting, please
inform DOE as soon as possible by contacting Ms. Regina Washington at
(202) 586-1214 or by email: [email protected] so that the
necessary procedures can be completed.
DOE requires visitors to have laptops and other devices, such as
tablets, checked upon entry into the building. Any person wishing to
bring these devices into the Forrestal Building will be required to
obtain a property pass. Visitors should avoid bringing these devices,
or allow an extra 45 minutes to check in. Please report to the
visitor's desk to have devices checked before proceeding through
security.
Due to the REAL ID Act implemented by the Department of Homeland
Security (DHS), there have been recent changes regarding ID
requirements for individuals wishing to enter Federal buildings from
specific states and U.S. territories. Driver's licenses from the
following states or territory will not be accepted for building entry
and one of the alternate forms of ID listed below will be required. DHS
has determined that regular driver's licenses (and ID cards) from the
following jurisdictions are not acceptable for entry into DOE
facilities: Alaska, American Samoa, Arizona, Louisiana, Maine,
Massachusetts, Minnesota, New York, Oklahoma, and Washington.
Acceptable alternate forms of Photo-ID include: U.S. Passport or
Passport Card; an Enhanced
[[Page 58198]]
Driver's License or Enhanced ID-Card issued by the states of Minnesota,
New York or Washington (Enhanced licenses issued by these states are
clearly marked Enhanced or Enhanced Driver's License); a military ID or
other Federal government issued Photo-ID card.
In addition, you can attend the public meeting via webinar. Webinar
registration information, participant instructions, and information
about the capabilities available to webinar participants will be
published on DOE's Web site at: https://www1.eere.energy.gov/buildings/appliance_standards/standards.aspx?productid=48&action=viewlive.
Participants are responsible for ensuring their systems are compatible
with the webinar software.
B. Procedure for Submitting Prepared General Statements for
Distribution
Any person who has plans to present a prepared general statement
may request that copies of his or her statement be made available at
the public meeting. Such persons may submit requests, along with an
advance electronic copy of their statement in PDF (preferred),
Microsoft Word or Excel, WordPerfect, or text (ASCII) file format, to
the appropriate address shown in the ADDRESSES section at the beginning
of this document. The request and advance copy of statements must be
received at least one week before the public meeting and may be
emailed, hand-delivered, or sent by mail. DOE prefers to receive
requests and advance copies via email. Please include a telephone
number to enable DOE staff to make follow-up contact, if needed.
C. Conduct of the Public Meeting
DOE will designate a DOE official to preside at the public meeting
and may also use a professional facilitator to aid discussion. The
meeting will not be a judicial or evidentiary-type public hearing, but
DOE will conduct it in accordance with section 336 of EPCA (42 U.S.C.
6306). A court reporter will be present to record the proceedings and
prepare a transcript. DOE reserves the right to schedule the order of
presentations and to establish the procedures governing the conduct of
the public meeting. After the public meeting, interested parties may
submit further comments on the proceedings as well as on any aspect of
the rulemaking until the end of the comment period.
The public meeting will be conducted in an informal, conference
style. DOE will present summaries of comments received before the
public meeting, allow time for prepared general statements by
participants, and encourage all interested parties to share their views
on issues affecting this rulemaking. Each participant will be allowed
to make a general statement (within time limits determined by DOE),
before the discussion of specific topics. DOE will allow, as time
permits, other participants to comment briefly on any general
statements.
At the end of all prepared statements on a topic, DOE will permit
participants to clarify their statements briefly and comment on
statements made by others. Participants should be prepared to answer
questions by DOE and by other participants concerning these issues. DOE
representatives may also ask questions of participants concerning other
matters relevant to this rulemaking. The official conducting the public
meeting will accept additional comments or questions from those
attending, as time permits. The presiding official will announce any
further procedural rules or modification of the above procedures that
may be needed for the proper conduct of the public meeting.
A transcript of the public meeting will be included in the docket,
which can be viewed as described in the Docket section at the beginning
of this document. In addition, any person may buy a copy of the
transcript from the transcribing reporter.
D. Submission of Comments
DOE will accept comments, data, and information regarding this
proposed rule no later than the date provided in the DATES section at
the beginning of this proposed rule. Interested parties may submit
comments using any of the methods described in the ADDRESSES section at
the beginning of this notice.
Under EPCA, DOE may not amass more than 270 days of public comment
during a test procedure rulemaking. (42 U.S.C. 6293(b)(2)) Since the
beginning of this test procedure rulemaking on June 2, 2010 (75 FR
31223), DOE has provided 216 days of public comment, in all.\29\ Thus,
DOE is providing 30 days of public comment for this SNOPR to ensure
that parties have a chance to comment throughout the rest of this
rulemaking.
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\29\ This includes the comment period from the April 2011 SNOPR
and the comment period extension, the October 2011 SNOPR and its
comment period extension, and the November 2015 SNOPR. See 76 FR
18105 (April 1, 2011); 76 FR 30555 (May 26, 2011); 76 FR 65616 (Oct.
24, 2011); 76 FR 79135 (Dec. 21, 2011); 80 FR 69277 (Nov. 9, 2015).
---------------------------------------------------------------------------
Submitting comments via regulations.gov. The regulations.gov Web
page will require you to provide your name and contact information.
Your contact information will be viewable to DOE Building Technologies
staff only. Your contact information will not be publicly viewable
except for your first and last names, organization name (if any), and
submitter representative name (if any). If your comment is not
processed properly because of technical difficulties, DOE will use this
information to contact you. If DOE cannot read your comment due to
technical difficulties and cannot contact you for clarification, DOE
may not be able to consider your comment.
However, your contact information will be publicly viewable if you
include it in the comment or in any documents attached to your comment.
Any information that you do not want to be publicly viewable should not
be included in your comment, nor in any document attached to your
comment. Persons viewing comments will see only first and last names,
organization names, correspondence containing comments, and any
documents submitted with the comments.
Do not submit to regulations.gov information for which disclosure
is restricted by statute, such as trade secrets and commercial or
financial information (hereinafter referred to as Confidential Business
Information (CBI)). Comments submitted through regulations.gov cannot
be claimed as CBI. Comments received through the Web site will waive
any CBI claims for the information submitted. For information on
submitting CBI, see the Confidential Business Information section.
DOE processes submissions made through regulations.gov before
posting. Normally, comments will be posted within a few days of being
submitted. However, if large volumes of comments are being processed
simultaneously, your comment may not be viewable for up to several
weeks. Please keep the comment tracking number that regulations.gov
provides after you have successfully uploaded your comment.
Submitting comments via email, hand delivery, or mail. Comments and
documents submitted via email, hand delivery, or mail also will be
posted to regulations.gov. If you do not want your personal contact
information to be publicly viewable, do not include it in your comment
or any accompanying documents. Instead, provide your contact
information on a cover letter. Include your first and last names, email
address, telephone number, and optional mailing address. The cover
letter will not be publicly viewable as long as it does not include any
comments
[[Page 58199]]
Include contact information each time you submit comments, data,
documents, and other information to DOE. If you submit via mail or hand
delivery, please provide all items on a CD, if feasible. It is not
necessary to submit printed copies. No facsimiles (faxes) will be
accepted.
Comments, data, and other information submitted to DOE
electronically should be provided in PDF (preferred), Microsoft Word or
Excel, WordPerfect, or text (ASCII) file format. Provide documents that
are not secured, written in English and free of any defects or viruses.
Documents should not contain special characters or any form of
encryption and, if possible, they should carry the electronic signature
of the author.
Campaign form letters. Please submit campaign form letters by the
originating organization in batches of between 50 to 500 form letters
per PDF or as one form letter with a list of supporters' names compiled
into one or more PDFs. This reduces comment processing and posting
time.
Confidential Business Information. According to 10 CFR 1004.11, any
person submitting information that he or she believes to be
confidential and exempt by law from public disclosure should submit via
email, postal mail, or hand delivery two well-marked copies: One copy
of the document marked confidential including all the information
believed to be confidential, and one copy of the document marked non-
confidential with the information believed to be confidential deleted.
Submit these documents via email or on a CD, if feasible. DOE will make
its own determination about the confidential status of the information
and treat it according to its determination.
Factors of interest to DOE when evaluating requests to treat
submitted information as confidential include: (1) A description of the
items; (2) whether and why such items are customarily treated as
confidential within the industry; (3) whether the information is
generally known by or available from other sources; (4) whether the
information has previously been made available to others without
obligation concerning its confidentiality; (5) an explanation of the
competitive injury to the submitting person which would result from
public disclosure; (6) when such information might lose its
confidential character due to the passage of time; and (7) why
disclosure of the information would be contrary to the public interest.
It is DOE's policy that all comments may be included in the public
docket, without change and as received, including any personal
information provided in the comments (except information deemed to be
exempt from public disclosure).
E. Issues on Which DOE Seeks Comment
Although DOE welcomes comments on any aspect of this proposal, DOE
is particularly interested in receiving comments and views of
interested parties concerning the following issues:
Issue 1: DOE requests comment on its proposed certification
requirements for outdoor units with no match. Also, DOE seeks comment
on what fin style options should be considered as options for CCMS
database data entry.
Issue 2: DOE requests comment on its proposed language in 429.16
related to allowable ICM ratings and compliance with regional
standards.
Issue 3: DOE requests comment on its proposal to allow a one-sided
tolerance on represented values of cooling and heating capacity that
allows underrating of any amount but only overrating up to 5 percent.
Issue 4: DOE seeks comments from interested parties about its
proposal to impose time delays to allow approach to equilibrium for
measurements of off-mode power for units with self-regulating crankcase
heaters. DOE requests comment regarding the 4-hour and 8-hour delay
times proposed for units without and with compressor sound blankets,
respectively.
Issue 5: DOE requests comment on its proposal to limit the internal
volume of pressure measurement systems for cooling/heating heat pumps
where the pressure measurement location may switch from liquid to vapor
state when changing operating modes and for all systems undergoing
cyclic tests. DOE also requests comment specifically on (a) the
proposed 0.25 cubic inch per 12,000 Btu/h maximum internal volume for
such systems, and (b) the proposals for default internal volumes to
assign to pressure transducers and gauges of 0.1 and 0.2 cubic inches,
respectively.
Issue 6: DOE requests comment on the proposal to require the use of
a bin-by-bin method to calculate EER and COP for intermediate-speed
operation for SEER and HSPF calculations for variable-speed units.
Issue 7: DOE requests comment on its proposed modifications to
requirements when using the outdoor air enthalpy method as the
secondary test method, including its proposal that the official test be
conducted without the outdoor air-side test apparatus connected.
Issue 8: DOE requests comments on its proposal to require
certification reports for coil-only units to indicate whether testing
was conducted using a time-delay relay to provide an off-cycle time
delay, and the duration of the time delay.
Issue 9: DOE requests comment on its proposal to limit the NGIFS of
tested coil-only single-split systems to 2.0 sq.in/Btu/hr.
Issue 10: DOE requests comments on its proposal to require that
full-speed tests conducted in 17[emsp14][deg]F and 35[emsp14][deg]F
ambient temperatures use the maximum compressor speed at which the
system controls would operate the compressor in normal operation in a
17[emsp14][deg]F ambient temperatures. DOE requests comment on the
proposed approach of using standardized slope factors for calculation
of representative performance at 47[emsp14][deg]F ambient temperature
for heat pumps for which the 47[emsp14][deg]F full-speed test cannot be
conducted at the same speed as the 17[emsp14][deg]F full-speed test.
Further, DOE requests comment on the specific slope factors proposed,
and/or data to show that different slope factors should be used.
Issue 11: DOE requests comments on its proposal to allow the full
speed test in 47[emsp14][deg]F ambient temperature that is used to
represent heat pump heating capacity, to use any speed that is no lower
than used for the 95[emsp14][deg]F full-speed cooling test for Appendix
M.
Issue 12: DOE requests comments on its clarifications regarding use
of break-in, including use of the certified break-in period for each
compressor of the unit, regardless of who conducts the test, prior to
any test period used to measure performance.
Issue 13: DOE requests comments on removing from section 2.2.3.a of
Appendix M the 5 percent tolerance for part load operation when
comparing the sum of nominal capacities of the indoor units and the
intended system part load capacity.
Issue 14: DOE requests comment on whether removing the statement
about insulating or sealing cased coils in Appendix M, section 2.2.c
would be sufficient to avoid confusion regarding whether sealing of
duct connections is allowed.
Issue 15: DOE requests comments on the proposed minimum external
static pressure requirements.
DOE proposes to establish the certification requirements for
Appendix M1 to require manufacturers to certify the kind(s) of CAC/HP
associated with the minimum external static pressure used in testing or
rating (i.e., ceiling-mount, wall-mount, mobile home, low-static, mid-
static, small duct high velocity, space constrained, or conventional/
not otherwise listed). In the case of mix-match ratings for multi-
[[Page 58200]]
split, multi-head mini-split, and multi-circuit systems, manufacturers
may select two kinds. In addition, models of outdoor units for which
some combinations distributed in commerce meet the definition for
ceiling-mount and wall-mount blower coil system are still required to
have at least one coil-only rating (which uses the 441W/1000 scfm
default fan power value) that is representative of the least efficient
coil distributed in commerce with the particular model of outdoor unit.
Mobile home systems are also required to have at least one coil-only
rating that is representative of the least efficient coil distributed
in commerce with the particular model of outdoor unit. DOE proposes to
specify a default fan power value of 406W/1000 scfm, rather than 441W/
1000 scfm, for mobile home coil-only systems. Details of this proposal
are discussed in detail in section III.C.2.
Issue 16: DOE requests comment on the proposed definitions for
kinds of CAC/HP associated with administering minimum external static
pressure requirements.
Issue 17: DOE requests comments on not including a reduced minimum
external static pressure requirement for blower coil or single-package
systems tested with a condensing furnace.
Issue 18: DOE requests comment on the proposed default fan power
value for coil-only mobile home systems. DOE also requests mobile home
indoor fan performance data for units of all capacities and that use
all available motor technologies in order to allow confirmation that
the proposed default value is a good representation for mobile home
units.
Issue 19: DOE requests comments on its proposed definition for
mobile home coil-only unit.
Issue 20: DOE requests comments on the adjustments to the proposals
for calculating HSPF for heat pumps and SEER for variable-speed heat
pumps.
Issue 21: DOE requests comments on the adjusted values of minimum
HSPF based on the HSPF efficiency levels recommended by the CAC/HP ECS
Working Group.
Issue 22: DOE requests comment on its proposal to require use of an
alternative HSPF rating approach (for heat pumps that raise minimum
compressor speed in ambient temperatures that impact the HSPF
calculation) that estimates minimum-speed performance (a) between 35
[deg]F and 47 [deg]F using the intermediate-speed frosting-operation
test at 35 [deg]F and the minimum-speed test at 47 [deg]F, and (b)
below 35 [deg]F assuming that minimum-speed and intermediate-speed
performance are the same. In addition, DOE requests comment on
including in certification reports for variable-speed heat pumps
whether this alternative approach was used to determine the rating.
Finally, DOE requests comment on whether any of the additional tests
that could be used to further improve the accuracy of variable-speed
heat pump performance estimates should be required in the test
procedure.
Issue 23: DOE requests comment on the proposals for evaluation of
heat pump capacity and power input as a function of ambient temperature
based on test measurements, both for cases where a 5 [deg]F test is
conducted and where it isn't.
Issue 24: DOE requests comment on the target wet bulb temperature
for the 5 [deg]F test.
Issue 25: DOE requests general comments regarding its proposal to
adopt an optional 5 [deg]F test and regarding any other details of the
related amendments proposed for calculation of HSPF.
Issue 26: DOE requests comments on whether the very-low-temperature
heating mode test for triple-capacity northern heat pumps should be
changed to a 5 [deg]F test for consistency with the proposed 5 [deg]F
variable-speed test.
Issue 27: DOE seeks comment on its estimate of the number of small
entities that may be impacted by the proposed test procedure.
Issue 28: DOE seeks comment on its estimate of the impact of the
proposed test procedure amendments on small entities.
VI. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this proposed
rule.
List of Subjects
10 CFR Part 429
Administrative practice and procedure, Confidential business
information, Energy conservation, Reporting and recordkeeping
requirements.
10 CFR Part 430
Administrative practice and procedure, Confidential business
information, Energy conservation, Energy conservation test procedures,
Household appliances, Imports, Incorporation by reference,
Intergovernmental relations, Small businesses.
Issued in Washington, DC, on August 1, 2016.
Kathleen B. Hogan,
Deputy Assistant Secretary for Energy Efficiency, Energy Efficiency and
Renewable Energy.
For the reasons stated in the preamble, DOE is proposing to amend
parts 429 and 430 of chapter II of title 10, subpart B, Code of Federal
Regulations, as set forth below:
PART 429--CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER
PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT
0
1. The authority citation for part 429 continues to read as follows:
Authority: 42 U.S.C. 6291-6317.
0
2. Section 429.11 is amended by revising paragraph (a) to read as
follows:
Sec. 429.11 General sampling requirements for selecting units to be
tested.
(a) When testing of covered products or covered equipment is
required to comply with section 323(c) of the Act, or to comply with
rules prescribed under sections 324, 325, or 342, 344, 345 or 346 of
the Act, a sample comprised of production units (or units
representative of production units) of the basic model being tested
must be selected at random and tested, and must meet the criteria found
in Sec. Sec. 429.14 through 429.62. Components of similar design may
be substituted without additional testing if the substitution does not
affect energy or water consumption. Any represented values of measures
of energy efficiency, water efficiency, energy consumption, or water
consumption for all individual models represented by a given basic
model must be the same, except for central air conditioners and central
air conditioning heat pumps, as specified in Sec. 429.16.
* * * * *
0
3. Section 429.16 is amended by:
0
a. Revising paragraph (a)(1);
0
b. Redesignating paragraphs (a)(3) and (a)(4) as (a)(4) and (a)(5) and
revising newly designated (a)(4)(i);
0
c. Adding new paragraph (a)(3);
0
d. Revising paragraph (b)(2)(i);
0
e. Revising the introductory text of paragraph (b)(3)(i), and revising
paragraphs (b)(3)(iii) and (b)(3)(iv);
0
f. Revising paragraphs (c)(1)(i)(B), (c)(3), (d)(3) and (d)(4);
0
g. Revising paragraphs (e)(2), (e)(3) and (e)(4); and
0
h. Revising paragraphs (f) introductory text, (f)(1), (f)(2), (f)(4),
and (f)(5).
[[Page 58201]]
The revisions and addition read as follows:
Sec. 429.16 Central air conditioners and central air conditioning
heat pumps.
(a) Determination of Represented Value--(1) Required represented
values. Determine the represented values (including SEER, EER, HSPF,
PW,OFF, cooling capacity, and heating capacity, as
applicable) for the individual models/combinations (or ``tested
combinations'') specified in the following table.
------------------------------------------------------------------------
Equipment Required represented
Category subcategory values
------------------------------------------------------------------------
Single-Package Unit........... Single-Package AC Every individual
(including Space- model distributed in
Constrained). commerce.
Single-Package HP
(including Space-
Constrained).
Outdoor Unit and Indoor Unit Single-Split- Every individual
(Distributed in Commerce by System AC with combination
OUM). Single-Stage or distributed in
Two-Stage commerce, including
Compressor all coil-only and
(including Space- blower coil
Constrained and combinations. Every
Small-Duct, High outdoor unit and
Velocity Systems indoor unit
(SDHV)). combination, must
have a coil-only
rating. For each
model of outdoor
unit, this must
include at least one
coil-only value that
is representative of
the least efficient
combination
distributed in
commerce with the
particular model of
outdoor unit.
Single-Split- Every individual
System AC with combination
Other Than distributed in
Single-Stage or commerce, including
Two-Stage all coil-only and
Compressor blower coil
(including Space- combinations.
Constrained and
SDHV).
Single-Split- Every individual
System HP combination
(including Space- distributed in
Constrained and commerce.
SDHV).
Multi-Split, For each model of
Multi-Circuit, outdoor unit, at a
or Multi-Head minimum, a non-
Mini-Split Split ducted ``tested
System--non-SDHV. combination.'' For
any model of outdoor
unit also sold with
models of ducted
indoor units, a
ducted ``tested
combination.'' When
determining
represented values
on or after January
1, 2023, the ducted
``tested
combination'' must
comprise the highest
static variety of
ducted indoor unit
distributed in
commerce (i.e.,
conventional, mid-
static, or low-
static). Additional
representations are
allowed, as
described in
paragraph (c)(3)(i)
of this section.
Multi-Split, For each model of
Multi-Circuit, outdoor unit, an
or Multi-Head SDHV ``tested
Mini-Split Split combination.''
System--SDHV. Additional
representations are
allowed, as
described in
paragraph (c)(3)(ii)
of this section.
Indoor Unit Only Distributed Single-Split- Every individual
in Commerce by ICM). System Air combination
Conditioner distributed in
(including Space- commerce.
Constrained and
SDHV).
Single-Split-
System Heat Pump
(including Space-
Constrained and
SDHV).
Multi-Split, For a model of indoor
Multi-Circuit, unit within each
or Multi-Head basic model, an SDHV
Mini-Split Split ``tested
System--SDHV. combination.''
Additional
representations are
allowed, as
described in section
(c)(3)(ii) of this
section.
--------------------------------------------------
Outdoor Unit with no Match Every model of
outdoor unit
distributed in
commerce (tested
with a model of coil-
only indoor unit as
specified in
paragraph (b)(2)(i)
of this section).
------------------------------------------------------------------------
* * * * *
(3) Refrigerants. If a model of outdoor unit (used in a single-
split, multi-split, multi-circuit, multi-head mini-split, and/or
outdoor unit with no match system) is distributed in commerce with
multiple refrigerants, a manufacturer must determine all represented
values for each refrigerant that can be used in an individual
combination of the basic model (including outdoor units with no match
or ``tested combinations'') without voiding the manufacturer's
warranty. This requirement may apply across the listed categories in
the table in paragraph (a)(1) of this section. If the warranty
information specifies acceptable refrigerant characteristics rather
than specific refrigerants and HCFC-22 meets these characteristics, a
manufacturer must determine represented values (including SEER, EER,
HSPF, PW,OFF, cooling capacity, and heating capacity, as
applicable) for, at a minimum, an outdoor unit with no match. If a
model of outdoor unit (used in a single-split, multi-split, multi-
circuit, multi-head mini-split, and/or outdoor unit with no match
system) is distributed in commerce without a specific refrigerant
specified or not charged with a specified refrigerant from the point of
manufacture, if the unit is shipped requiring addition of more than a
pound of refrigerant to meet the charge recommended by the
manufacturer's installation instructions (or section 2.2.5 of appendix
M or appendix M1), or if the unit is shipped with any amount of charge
of R-407C, a manufacturer must determine represented values (including
SEER, EER, HSPF, PW,OFF, cooling capacity, and heating
capacity, as applicable) for, at a minimum, an outdoor unit with no
match.
(4) * * *
(i) Regional. A basic model may only be certified as compliant with
a regional standard if all individual combinations within that basic
model meet the regional standard for which it is certified. A model of
outdoor unit that is certified below a regional standard can only be
rated and certified as compliant with a regional standard if the model
of outdoor unit has a unique model number and has been certified as a
different basic model for distribution in each region. An ICM cannot
certify an individual combination with a rating that is compliant with
a regional standard if the individual combination
[[Page 58202]]
includes a model of outdoor unit that the OUM has certified with a
rating that is not compliant with a regional standard. Conversely, an
ICM cannot certify an individual combination with a rating that is not
compliant with a regional standard if the individual combination
includes a model of outdoor unit that an OUM has certified with a
rating that is compliant with a regional standard.
* * * * *
(b) * * *
(2) Individual model/combination selection for testing. (i) The
table identifies the minimum testing requirements for each basic model
that includes multiple individual models/combinations; if a basic model
spans multiple categories listed in the table, multiple testing
requirements apply. For each basic model that includes only one
individual model/combination, test that individual model/combination.
For single-split-system non-space-constrained air conditioners and heat
pumps, when testing is required in accordance with 10 CFR part 430,
subpart B, appendix M1, these requirements do not apply until July 1,
2024, provided that the manufacturer is certifying compliance of all
basic models using an AEDM in accordance with paragraph (c)(1)(i)(B) of
this section and paragraph (e)(2)(i)(A) of Sec. 429.70.
----------------------------------------------------------------------------------------------------------------
Category Equipment subcategory Must test: With:
----------------------------------------------------------------------------------------------------------------
Single-Package Unit............... Single-Package AC The lowest SEER N/A.
(including Space- individual model.
Constrained).
Single-Package HP
(including Space-
Constrained).
Outdoor Unit and Indoor Unit Single-Split-System AC The model of outdoor A model of coil-only
(Distributed in Commerce by OUM). with Single-Stage or Two- unit. indoor unit meeting the
Stage Compressor requirements of section
(including Space- 2.2h of appendix M or M1
Constrained and Small- to subpart B of part
Duct, High Velocity 430.
Systems (SDHV)).
Single-Split-System AC The model of outdoor A model of indoor unit.
with Other Than Single- unit. If the tested model of
Stage or Two-Stage indoor unit is coil-
Compressor (including only, it must meet the
Space-Constrained and requirements of section
SDHV). 2.2h of appendix M or M1
Single-Split-System HP to subpart B of part
(including Space- 430.
Constrained and SDHV).
Multi-Split, Multi- The model of outdoor At a minimum, a ``tested
Circuit, or Multi-Head unit. combination'' composed
Mini-Split Split System-- entirely of non-ducted
non-SDHV. indoor units. For any
models of outdoor units
also sold with models of
ducted indoor units,
test a second ``tested
combination'' composed
entirely of ducted
indoor units (in
addition to the non-
ducted combination). If
testing under appendix
M1 to subpart B of part
430, the ducted ``tested
combination'' must
comprise the highest
static variety of ducted
indoor unit distributed
in commerce (i.e.,
conventional, mid-
static, or low-static).
Multi-Split, Multi- The model of outdoor A ``tested combination''
Circuit, or Multi-Head unit. composed entirely of
Mini-Split Split System-- SDHV indoor units.
SDHV.
Indoor Unit Only (Distributed in Single-Split-System Air A model of indoor The least efficient model
Commerce by ICM). Conditioner (including unit. of outdoor unit with
Space-Constrained and Nothing, as long as which it will be paired
SDHV). an equivalent air where the least
Single-Split-System Heat conditioner basic efficient model of
Pump (including Space- model has been outdoor unit is the
Constrained and SDHV). tested.. model of outdoor unit in
If an equivalent air the lowest SEER
conditioner basic combination as certified
model has not been by the OUM. If there are
tested, must test a multiple models of
model of indoor unit. outdoor unit with the
same lowest SEER
represented value, the
ICM may select one for
testing purposes.
Multi-Split, Multi- A model of indoor A ``tested combination''
Circuit, or Multi-Head unit. composed entirely of
Mini-Split Split System-- SDHV indoor units, where
SDHV. the outdoor unit is the
least efficient model of
outdoor unit with which
the SDHV indoor unit
will be paired. The
least efficient model of
outdoor unit is the
model of outdoor unit in
the lowest SEER
combination as certified
by the OUM. If there are
multiple models of
outdoor unit with the
same lowest SEER
represented value, the
ICM may select one for
testing purposes.
---------------------------------------------------------------
Outdoor Unit with No Match The model of outdoor A model of coil-only
unit. indoor unit meeting the
requirements of section
2.2e of appendix M or M1
to subpart B of part
430.
----------------------------------------------------------------------------------------------------------------
* * * * *
(3) Sampling plans and represented values. For individual models
(for single-package systems) or individual combinations (for split-
systems, including ``tested combinations'' for multi-split, multi-
circuit, and multi-head mini-split systems) with represented values
determined through testing, each individual model/combination (or
``tested combination'') must have a sample of sufficient size
[[Page 58203]]
tested in accordance with the applicable provisions of this subpart.
For heat pumps (other than heating-only heat pumps), all units of the
sample population must be tested in both the cooling and heating modes
and the results used for determining all representations. The
represented values for any individual model/combination must be
assigned such that:
* * * * *
(iii) Cooling Capacity. The represented value of cooling capacity
must be a self-declared value that is no more than 105 percent of the
mean of the cooling capacities measured for the units in the sample,
rounded:
(A) To the nearest 100 Btu/h if cooling capacity is less than
20,000 Btu/h,
(B) To the nearest 200 Btu/h if cooling capacity is greater than or
equal to 20,000 Btu/h but less than 38,000 Btu/h, and
(C) To the nearest 500 Btu/h if cooling capacity is greater than or
equal to 38,000 Btu/h and less than 65,000 Btu/h.
(iv) Heating Capacity. The represented value of heating capacity
must be a self-declared value that is no more than 105 percent of the
mean of the heating capacities measured for the units in the sample,
rounded:
(A) To the nearest 100 Btu/h if heating capacity is less than
20,000 Btu/h,
(B) To the nearest 200 Btu/h if heating capacity is greater than or
equal to 20,000 Btu/h but less than 38,000 Btu/h, and
(C) To the nearest 500 Btu/h if heating capacity is greater than or
equal to 38,000 Btu/h and less than 65,000 Btu/h.
(c) * * *
(1) * * *
(i) * * *
(B) The representative values of the measures of energy efficiency
or energy consumption through the application of an AEDM in accordance
with paragraph (d) of this section and Sec. 429.70. An AEDM may only
be used to determine represented values for individual models or
combinations in a basic model other than the individual model or
combination(s) required for mandatory testing under paragraph (b)(2) of
this section, except that, for single-split, non-space-constrained
systems, when testing is required in accordance with 10 CFR part 430,
subpart B, appendix M1, an AEDM may be used to rate the individual
model or combination(s) required for mandatory testing under paragraph
(b)(2) of this section until July 1, 2024, in accordance with paragraph
(e)(2)(i)(A) of Sec. 429.70.
* * * * *
(3) For multi-split systems, multi-circuit systems, and multi-head
mini-split systems. The following applies:
(i) For basic models that include additional varieties of ducted
indoor units (i.e., conventional, low-static, or mid-static) other than
the one for which representation is required in paragraph (a)(1) of
this section, if a manufacturer chooses to make a representation, the
manufacturer must conduct testing of a tested combination in accordance
with 10 CFR part 430, subpart B, appendix M1 and according to the
requirements in paragraph (b)(3)(i) of this section.
(ii) For basic models composed of both non-ducted and ducted
combinations, the represented value based on testing in accordance with
10 CFR part 430, subpart B, appendix M for the mixed non-ducted/ducted
combination is the mean of the represented values for the non-ducted
and ducted combinations as determined in accordance with paragraph
(b)(3)(i) of this section. For basic models that include mixed
combinations of indoor units (any two kinds of non-ducted, low-static,
mid-static, and conventional ducted indoor units), the represented
value based on testing in accordance with 10 CFR part 430, subpart B,
appendix M1 for the mixed combination is the mean of the represented
values for the individual component combinations as determined in
accordance with paragraph (b)(3)(i) of this section.
(iii) For basic models composed of both SDHV and non-ducted or
ducted combinations, the represented value based on testing in
accordance with 10 CFR part 430, subpart B, appendix M for the mixed
SDHV/non-ducted or SDHV/ducted combination is the mean of the
represented values for the SDHV, non-ducted, or ducted combinations, as
applicable, as determined in accordance with paragraph (b)(3)(i) of
this section. For basic models including mixed combinations of SDHV and
another kind of indoor unit (any of non-ducted, low-static, mid-static,
and conventional ducted), the represented value based on testing in
accordance with 10 CFR part 430, subpart B, appendix M1 for the mixed
SDHV/other combination is the mean of the represented values for the
SDHV and other tested combination as determined in accordance with
paragraph (b)(3)(i) of this section.
(iv) All other individual combinations of models of indoor units
for the same model of outdoor unit for which the manufacturer chooses
to make representations must be rated as separate basic models, and the
provisions of paragraphs (b)(1) through (3) and (c)(3)(i) through(iii)
of this section apply.
(v) With respect to PW,OFF only, for every individual
combination (or ``tested combination'') within a basic model tested
pursuant to paragraph (b)(2) of this section, but for which
PW,OFF testing was not conducted, the representative values
of PW,OFF may be assigned through either:
(A) The testing result from an individual model or combination of
similar off-mode construction, or
(B) Application of an AEDM in accordance with paragraph (d) of this
section and Sec. 429.70.
(d) * * *
(3) Cooling capacity. The represented value of cooling capacity of
an individual model/combination must be no greater than 105% of the
cooling capacity output simulated by the AEDM.
(4) Heating capacity. The represented value of heating capacity of
an individual model/combination must be no greater than 105% of the
heating capacity output simulated by the AEDM.
(e) * * *
(2) Public product-specific information. Pursuant to Sec.
429.12(b)(13), for each individual model (for single-package systems)
or individual combination (for split-systems, including outdoor units
with no match and ``tested combinations'' for multi-split, multi-
circuit, and multi-head mini-split systems), a certification report
must include the following public product-specific information: The
seasonal energy efficiency ratio (SEER in British thermal units per
Watt-hour (Btu/W-h)); the average off mode power consumption
(PW,OFF in Watts); the cooling capacity in British thermal
units per hour (Btu/h); the region(s) in which the basic model can be
sold; when certifying compliance with amended energy conservation
standards, the kind(s) of air conditioner or heat pump associated with
the minimum external static pressure used in testing or rating
(ceiling-mount, wall-mount, mobile home, low-static, mid-static, small
duct high velocity, space constrained, or conventional/not otherwise
listed); and
(i) For heat pumps, the heating seasonal performance factor (HSPF
in British thermal units per Watt-hour (Btu/W-h));
(ii) For central air conditioners (excluding space constrained
products), the energy efficiency ratio (EER in British thermal units
per Watt-hour (Btu/W-h));
(iii) For single-split-systems, whether the represented value is
for a coil-only or blower coil system;
[[Page 58204]]
(iv) For multi-split, multiple-circuit, and multi-head mini-split
systems (including VRF and SDHV), when certifying compliance with
current energy conservation standards, whether the represented value is
for a non-ducted, ducted, mixed non-ducted/ducted system, SDHV, mixed
non-ducted/SDHV system, or mixed ducted/SDHV system;
(v) For all split systems including outdoor units with no match,
the refrigerant.
(3) Basic and individual model numbers. The basic model number and
individual model number(s) required to be reported under Sec.
429.12(b)(6) must consist of the following:
----------------------------------------------------------------------------------------------------------------
Individual model Nos.
Equipment type Basic model No. -------------------------------------------------------------
1 2 3
----------------------------------------------------------------------------------------------------------------
Single-Package (including Space- Number unique to Package............... N/A.............. N/A.
Constrained). the basic model.
Single-Split System (including Number unique to Outdoor Unit.......... Indoor Unit...... Air Mover (could
Space-Constrained and SDHV). the basic model. be same as
indoor unit if
fan is part of
indoor unit
model number).
Multi-Split, Multi-Circuit, and Number unique to Outdoor Unit.......... When certifying a When certifying a
Multi-Head Mini-Split System the basic model. basic model basic model
(including SDHV). based on tested based on tested
combination(s): combination(s):
* * *............ * * *
When certifying When certifying
an individual an individual
combination: combination: Air
Indoor Unit(s). Mover(s).
Outdoor Unit with No Match..... Number unique to Outdoor Unit.......... N/A.............. N/A.
the basic model.
----------------------------------------------------------------------------------------------------------------
(4) Additional product-specific information. Pursuant to Sec.
429.12(b)(13), for each individual model/combination (including outdoor
units with no match and ``tested combinations''), a certification
report must include the following additional product-specific
information: the cooling full load air volume rate for the system or
for each indoor unit as applicable (in cubic feet per minute of
standard air (scfm)); the air volume rates for other test conditions
including minimum cooling air volume rate, intermediate cooling air
volume rate, full load heating air volume rate, minimum heating air
volume rate, intermediate heating air volume rate, and nominal heating
air volume rate (scfm) for the system or for each indoor unit as
applicable, if different from the cooling full load air volume rate;
whether the individual model uses a fixed orifice, thermostatic
expansion valve, electronic expansion valve, or other type of metering
device; the duration of the compressor break-in period, if used;
whether the optional tests were conducted to determine the Cc value
used to represent cooling mode cycling losses or whether the default
value was used; the temperature at which the crankcase heater with
controls is designed to turn on, if applicable; the duration of the
crankcase heater time delay for the shoulder season and heating season,
if such time delay is employed; the maximum time between defrosts as
allowed by the controls (in hours); whether an inlet plenum was
installed during testing; the duration of the indoor fan time delay, if
used; and
(i) For heat pumps, whether the optional tests were conducted to
determine the Cc value or whether the default value was used;
(ii) For multi-split, multiple-circuit, and multi-head mini-split
systems, the number of indoor units tested with the outdoor unit; the
nominal cooling capacity of each indoor unit and outdoor unit in the
combination; and the indoor units that are not providing heating or
cooling for part-load tests;
(iii) For ducted systems having multiple indoor fans within a
single indoor unit, the number of indoor fans; the nominal cooling
capacity of the indoor unit and outdoor unit; which fan(s) operate to
attain the full-load air volume rate when controls limit the
simultaneous operation of all fans within the single indoor unit; and
the allocation of the full-load air volume rate to each operational fan
when different capacity blowers are connected to the common duct;
(iv) For blower coil systems, the airflow-control settings
associated with full load cooling operation; and the airflow-control
settings or alternative instructions for setting fan speed to the speed
upon which the rating is based;
(v) For models with time-adaptive defrost control, the frosting
interval to be used during Frost Accumulation tests and the procedure
for manually initiating the defrost at the specified time;
(vi) For models of indoor units designed for both horizontal and
vertical installation or for both up-flow and down-flow vertical
installations, the orientation used for testing;
(vii) For variable speed models, the compressor frequency set
points, and the required dip switch/control settings for step or
variable components; and
(viii) For variable speed heat pumps, whether the optional
H42 low temperature test was used to characterize
performance at temperatures below 17[emsp14][deg]F, whether the
H1N or H12 test speed is the same as the
H32 test speed, and whether the alternative test required
for minimum-speed-limiting variable-speed heat pumps was used;
(ix) For models of outdoor units with no match, the following
characteristics of the indoor coil: the face area, the coil depth in
the direction of airflow, the fin density (fins per inch), the fin
material, the fin style, the tube diameter, the tube material, and the
numbers of tubes high and deep;
(x) For single-split-system coil-only ratings, NGIFS and the OFF-
cycle time delay for the indoor fan, if used for certification testing;
and
(xi) For central air conditioners and heat pumps that have two-
capacity compressors that lock out low capacity operation for cooling
at higher outdoor temperatures and/or heating at lower outdoor
temperatures, the outdoor temperature(s) at which the unit locks out
low capacity operation.
(f) Represented values for the Federal Trade Commission. Use the
following represented value determinations to meet the requirements of
the Federal Trade Commission.
(1) Annual Operating Cost--Cooling. Determine the represented value
of estimated annual operating cost for cooling-only units or the
cooling portion
[[Page 58205]]
of the estimated annual operating cost for air-source heat pumps that
provide both heating and cooling by calculating the product of:
(i) The value determined in paragraph (A) if using appendix M to
subpart B of part 430 or the value determined in paragraph (B) if using
appendix M1 to subpart B of part 430;
(A) the quotient of the represented value of cooling capacity, in
Btu's per hour as determined in paragraph (b)(3)(i)(C) of this section,
divided by the represented value of SEER, in Btu's per watt-hour, as
determined in paragraph (b)(3)(i)(B) of this section;
(B) the quotient of the represented value of cooling capacity, in
Btu's per hour as determined in paragraph (b)(3)(i)(C) of this section,
and multiplied by 0.93 for variable-speed heat pumps only, divided by
the represented value of SEER, in Btu's per watt-hour, as determined in
paragraph (b)(3)(i)(B) of this section.
(ii) The representative average use cycle for cooling of 1,000
hours per year;
(iii) A conversion factor of 0.001 kilowatt per watt; and
(iv) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act.
(2) Annual Operating Cost--Heating. Determine the represented value
of estimated annual operating cost for air-source heat pumps that
provide only heating or for the heating portion of the estimated annual
operating cost for air-source heat pumps that provide both heating and
cooling, as follows:
(i) When using appendix M to subpart B of part 430, the product of:
(A) The quotient of the mean of the standardized design heating
requirement for the sample, in Btu's per hour, nearest to the Region IV
minimum design heating requirement, determined for each unit in the
sample in section 4.2 of appendix M to subpart B of part 430, divided
by the represented value of heating seasonal performance factor (HSPF),
in Btu's per watt-hour, calculated for Region IV corresponding to the
above-mentioned standardized design heating requirement, as determined
in paragraph (b)(3)(i)(B) of this section;
(B) The representative average use cycle for heating of 2,080 hours
per year;
(C) The adjustment factor of 0.77, which serves to adjust the
calculated design heating requirement and heating load hours to the
actual load experienced by a heating system;
(D) A conversion factor of 0.001 kilowatt per watt; and
(E) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act;
(ii) When using appendix M1 to subpart B of part 430, the product
of:
(A) The quotient of the represented value of cooling capacity (for
air-source heat pumps that provide both cooling and heating) in Btu's
per hour, as determined in paragraph (b)(3)(i)(C) of this section, or
the represented value of heating capacity (for air-source heat pumps
that provide only heating), as determined in paragraph (b)(3)(i)(D) of
this section, divided by the represented value of heating seasonal
performance factor (HSPF), in Btu's per watt-hour, calculated for
Region IV, as determined in paragraph (b)(3)(i)(B) of this section;
(B) The representative average use cycle for heating of 1,572 hours
per year;
(C) The adjustment factor of 1.15 (for heat pumps that are not
variable-speed) or 1.07 (for heat pumps that are variable-speed), which
serves to adjust the calculated design heating requirement and heating
load hours to the actual load experienced by a heating system;
(D) A conversion factor of 0.001 kilowatt per watt; and
(E) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act;
* * * * *
(4) Regional Annual Operating Cost--Cooling. Determine the
represented value of estimated regional annual operating cost for
cooling-only units or the cooling portion of the estimated regional
annual operating cost for air-source heat pumps that provide both
heating and cooling by calculating the product of:
(i) The value determined in paragraph (A) if using appendix M to
subpart B of part 430 or the value determined in paragraph (B) if using
appendix M1 to subpart B of part 430;
(A) the quotient of the represented value of cooling capacity, in
Btu's per hour as determined in paragraph (b)(3)(i)(C) of this section,
divided by the represented value of SEER, in Btu's per watt-hour, as
determined in paragraph (b)(3)(i)(B) of this section;
(B) the quotient of the represented value of cooling capacity, in
Btu's per hour as determined in paragraph (b)(3)(i)(C) of this section,
and multiplied by 0.93 for variable-speed heat pumps only, divided by
the represented value of SEER, in Btu's per watt-hour, as determined in
paragraph (b)(3)(i)(B) of this section;
(ii) The value determined in paragraph (A) if using appendix M to
subpart B of part 430 or the value determined in paragraph (B) if using
appendix M1 to subpart B of part 430;
(A) the estimated number of regional cooling load hours per year
determined from Table 21 in section 4.4 of appendix M to subpart B of
part 430;
(B) the estimated number of regional cooling load hours per year
determined from Table 20 in section 4.4 of appendix M1 to subpart B of
part 430;
(iii) A conversion factor of 0.001 kilowatts per watt; and
(iv) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act.
(5) Regional Annual Operating Cost--Heating. Determine the
represented value of estimated regional annual operating cost for air-
source heat pumps that provide only heating or for the heating portion
of the estimated regional annual operating cost for air-source heat
pumps that provide both heating and cooling as follows:
(i) When using appendix M to subpart B of part 430, the product of:
(A) The estimated number of regional heating load hours per year
determined from Table 21 in section 4.4 of appendix M to subpart B of
part 430;
(B) The quotient of the mean of the standardized design heating
requirement for the sample, in Btu's per hour, for the appropriate
generalized climatic region of interest (i.e., corresponding to the
regional heating load hours from ``A'') and determined for each unit in
the sample in section 4.2 of appendix M to subpart B of part 430,
divided by the represented value of HSPF, in Btu's per watt-hour,
calculated for the appropriate generalized climatic region of interest
and corresponding to the above-mentioned standardized design heating
requirement, and determined in paragraph (b)(3)(i)(B);
(C) The adjustment factor of 0.77; which serves to adjust the
calculated design heating requirement and heating load hours to the
actual load experienced by a heating system;
(D) A conversion factor of 0.001 kilowatts per watt; and
(E) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act.
(ii) When using appendix M1 to subpart B of part 430, the product
of:
(A) The estimated number of regional heating load hours per year
determined from Table 20 in section 4.4 of appendix M1 to subpart B of
part 430;
(B) The quotient of the represented value of cooling capacity (for
air-source
[[Page 58206]]
heat pumps that provide both cooling and heating) in Btu's per hour, as
determined in paragraph (b)(3)(i)(C) of this section, or the
represented value of heating capacity (for air- source heat pumps that
provide only heating), as determined in paragraph (b)(3)(i)(D) of this
section, divided by the represented value of HSPF, in Btu's per watt-
hour, calculated for the appropriate generalized climatic region of
interest, and determined in paragraph (b)(3)(i)(B) of this section;
(C) The adjustment factor of 1.15 (for heat pumps that are not
variable-speed) or 1.07 (for heat pumps that are variable-speed), which
serves to adjust the calculated design heating requirement and heating
load hours to the actual load experienced by a heating system;
(D) A conversion factor of 0.001 kilowatts per watt; and
(E) The representative average unit cost of electricity in dollars
per kilowatt-hour as provided pursuant to section 323(b)(2) of the Act.
* * * * *
0
4. Section 429.70 is amended by revising paragraph (e)(2)(i) and the
introductory text of paragraph (e)(5)(iv) to read as follows:
Sec. 429.70 Alternative methods for determining energy efficiency or
energy use.
* * * * *
(e) * * *
(2) * * *
(i) Conduct minimum testing and compare to AEDM output as described
in paragraphs (A) and (B) respectively.
(A) Minimum testing. (1) For non-space constrained single-split
system air conditioners and heat pumps rated based on testing in
accordance with appendix M to subpart B of part 430, the manufacturer
must test each basic model as required under Sec. 429.16(b)(2). Until
July 1, 2024, for non-space constrained single-split-system air
conditioners and heat pumps rated based on testing in accordance with
appendix M1 to subpart B of part 430, the manufacturer must test a
single-unit sample from 20 percent of the basic models distributed in
commerce to validate the AEDM. On or after July 1, 2024, for non-space
constrained single-split-system air conditioners and heat pumps rated
based on testing in accordance with appendix M1 to subpart B of part
430, the manufacturer must complete testing of each basic model as
required under Sec. 429.16(b)(2).
(2) For other than non-space constrained single-split-system air
conditioners and heat pumps, the manufacturer must test each basic
model as required under Sec. 429.16(b)(2).
(B) Using the AEDM, calculate the energy use or efficiency for each
of the tested individual models/combinations within each basic model.
Compare the represented value based on testing and the AEDM energy use
or efficiency output according to paragraph (e)(2)(ii) of this section.
The manufacturer is responsible for ensuring the accuracy and
reliability of the AEDM and that their representations are appropriate
and the models being distributed in commerce meet the applicable
standards, regardless of the amount of testing required in paragraphs
(e)(2)(i)(A) and (e)(2)(i)(B) of this section.
* * * * *
(5) * * *
(iv) Failure to meet certified value. If an individual model/
combination tests worse than its certified value (i.e., lower than the
certified efficiency value or higher than the certified consumption
value) by more than 5 percent, or the test results in cooling capacity
that is greater than 105 percent of its certified cooling capacity, DOE
will notify the manufacturer. DOE will provide the manufacturer with
all documentation related to the test set up, test conditions, and test
results for the unit. Within the timeframe allotted by DOE, the
manufacturer:
* * * * *
PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS
0
5. The authority citation for part 430 continues to read as follows:
Authority: 42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.
Sec. 430.3 [Amended]
0
6. Section 430.3 is amended by removing, in paragraphs (b)(2), (c)(1),
(c)(3), (g)(2), (g)(4), (g)(7), (g)(8), (g)(9), (g)(10) and (g)(13),
``appendix M'' and adding in its place, ``appendices M and M1''.
0
7. Section 430.23 is amended by revising paragraph (m) to read as
follows:
Sec. 430.23 Test procedures for the measurement of energy and water
consumption.
* * * * *
(m) Central air conditioners and heat pumps. See the note at the
beginning of appendix M and M1 to determine the appropriate test
method. Determine all values discussed in this section using a single
appendix.
(1) Determine cooling capacity from the steady-state wet-coil test
(A or A2 Test), as described in section 3.2 of appendix M or M1 to this
subpart, and rounded off to the nearest
(i) To the nearest 50 Btu/h if cooling capacity is less than 20,000
Btu/h;
(ii) To the nearest 100 Btu/h if cooling capacity is greater than
or equal to 20,000 Btu/h but less than 38,000 Btu/h; and
(iii) To the nearest 250 Btu/h if cooling capacity is greater than
or equal to 38,000 Btu/h and less than 65,000 Btu/h.
(2) Determine seasonal energy efficiency ratio (SEER) as described
in section 4.1 of appendix M or M1 to this subpart, and round off to
the nearest 0.025 Btu/W-h.
(3) Determine EER as described in section 4.7 of appendix M or M1
to this subpart, and round off to the nearest 0.025 Btu/W-h.
(4) Determine heating seasonal performance factors (HSPF) as
described in section 4.2 of appendix M or M1 to this subpart, and round
off to the nearest 0.025 Btu/W-h.
(5) Determine average off mode power consumption as described in
section 4.3 of appendix M or M1 to this subpart, and round off to the
nearest 0.5 W.
(6) Determine all other measures of energy efficiency or
consumption or other useful measures of performance using appendix M or
M1 of this subpart.
* * * * *
0
8. Appendix M to subpart B of part 430 is amended by:
0
a. Revising the definition of ``service coil'' in Section 1.2.,
Definitions;
0
b. Revising paragraph c. and adding paragraphs g. and h. in Section
2.2, Test Unit Installation Requirements;
0
c. Revising paragraph a. in section 2.2.3;
0
d. Removing in, Section 2.10.1, paragraph (c) first sentence, the word
``preliminary'' and adding in its place the word ``non-ducted'';
0
e. Revising section 3.1.7;
0
f. Revising the introductory paragraph of section 3.5.1;
0
g. Revising section 3.6.4;
0
h. Revising section 3.11.1;
0
i. Revising section 3.11.1.1;
0
j. Revising section 3.11.1.2;
0
l. Revising paragraphs b., and d., in section 3.13.2;
0
m. Revising the last paragraph in section 4.1.3;
0
n. Revising section 4.1.4.2;
0
o. Revising paragraph b., in section 4.2;
0
p. Redesignating paragraph c. as paragraph d. in section 4.2 and adding
paragraph c., respectively;
0
q. Revising the first paragraph in section 4.2.3;
[[Page 58207]]
0
r. Revising the second paragraph in section 4.2.4; and
0
s. Revising section 4.2.4.2.
The additions and revisions read as follows:
Appendix M to Subpart B of Part 430--Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps
* * * * *
1.2 Definitions
* * * * *
Service coil means an arrangement of refrigerant-to-air heat
transfer coil(s), condensate drain pan, sheet metal or plastic parts
to direct/route airflow over the coil(s), which may or may not
include external cabinetry and/or a cooling mode expansion device,
distributed in commerce solely for replacing an uncased coil or
cased coil that has already been placed into service, and that has
been labeled ``for indoor coil replacement only'' on the nameplate
and in manufacturer technical and product literature. The model
number for any service coil must include some mechanism (e.g., an
additional letter or number) for differentiating a service coil from
a coil intended for an indoor unit.
* * * * *
2.2 Test Unit Installation Requirements.
* * * * *
c. Testing a ducted unit without having an indoor air filter
installed is permissible as long as the minimum external static
pressure requirement is adjusted as stated in Table 3, note 3 (see
section 3.1.4 of this appendix). Except as noted in section 3.1.10
of this appendix, prevent the indoor air supplementary heating coils
from operating during all tests. For uncased coils, create an
enclosure using 1 inch fiberglass foil-faced ductboard having a
nominal density of 6 pounds per cubic foot. Or alternatively,
construct an enclosure using sheet metal or a similar material and
insulating material having a thermal resistance (``R'' value)
between 4 and 6 hr[middot]ft\2\[middot][deg]F/Btu. Size the
enclosure and seal between the coil and/or drainage pan and the
interior of the enclosure as specified in installation instructions
shipped with the unit. Also seal between the plenum and inlet and
outlet ducts.
* * * * *
g. If pressure measurement devices are connected to refrigerant
lines at locations where the refrigerant state changes from liquid
to vapor for different parts of the test (e.g. heating mode vs.
cooling mode, on-cycle vs. off-cycle during cyclic test), the total
internal volume of the pressure measurement system (transducers,
gauges, connections, and lines) must be no more than 0.25 cubic
inches per 12,000 Btu/h certified cooling capacity. Calculate total
system internal volume using internal volume reported for pressure
transducers and gauges in product literature, if available. If such
information is not available, use the value of 0.1 cubic inches
internal volume for each pressure transducer, and 0.2 cubic inches
for each pressure gauge.
h. For single-split-system coil-only air conditioners, test
using an indoor coil that has a normalized gross indoor fin surface
(NGIFS) no greater than 2.0 square inches per British thermal unit
per hour (sq. in./Btu/hr). NGIFS is calculated as follows:
NGIFS = 2 x Lf x Wf x Nf / Qc(95)
Where:
Lf = Indoor coil fin length in inches, also height of the
coil transverse to the tubes.
Wf = Indoor coil fin width in inches, also depth of the
coil.
Nf = Number of fins.
Qc = the measured space cooling capacity of the tested outdoor unit/
indoor unit combination as determined from the A2 or A Test
whichever applies, Btu/h.
* * * * *
2.2.3 Special Requirements for Multi-Split Air Conditioners and Heat
Pumps and Ducted Systems Using a Single Indoor Section Containing
Multiple Indoor Blowers That Would Normally Operate Using Two or More
Indoor Thermostats.
* * * * *
a. Additional requirements for multi-split air conditioners and
heat pumps. For any test where the system is operated at part load
(i.e., one or more compressors ``off'', operating at the
intermediate or minimum compressor speed, or at low compressor
capacity), record the indoor coil(s) that are not providing heating
or cooling during the test. For variable-speed systems, the
manufacturer must designate in the certification report at least one
indoor unit that is not providing heating or cooling for all tests
conducted at minimum compressor speed.
* * * * *
3.1 * * *
* * * * *
3.1.7 Test Sequence
Before making test measurements used to calculate performance,
operate the equipment for a ``break-in'' period, which may not
exceed 20 hours. Each compressor of the unit must undergo this
``break-in'' period. Record the duration of the break-in period.
When testing a ducted unit (except if a heating-only heat pump),
conduct the A or A2 Test first to establish the cooling full-load
air volume rate. * * *
* * * * *
3.5.1 Procedures When Testing Ducted Systems
The automatic controls that are normally installed with the test
unit must govern the OFF/ON cycling of the air moving equipment on
the indoor side (exhaust fan of the airflow measuring apparatus and
the indoor blower of the test unit). For ducted coil-only systems
rated based on using a fan time-delay relay, control the indoor coil
airflow according to the OFF delay listed by the manufacturer in the
certification report. For ducted units having a variable-speed
indoor blower that has been disabled (and possibly removed), start
and stop the indoor airflow at the same instances as if the fan were
enabled. * * *
* * * * *
3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor
a. Conduct one maximum temperature test (H01), two
high temperature tests (H1N and H11), one
frost accumulation test (H2V), and one low temperature
test (H32). Conducting one or both of the following tests
is optional: An additional high temperature test (H12)
and an additional frost accumulation test (H22). Conduct
the optional maximum temperature cyclic (H0C1) test to
determine the heating mode cyclic-degradation coefficient,
CD\h\. If this optional test is conducted but yields a
tested CD\h\ that exceeds the default CD\h\ or
if the optional test is not conducted, assign CD\h\ the
default value of 0.25. Test conditions for the eight tests are
specified in Table 13. The compressor shall operate at the same
heating full speed, measured by RPM or power input frequency (Hz),
equal to the maximum speed at which the system controls would
operate the compressor in normal operation in 17 [deg]F ambient
temperature, for the H12, H22 and
H32 tests. For a cooling/heating heat pump, the
compressor shall operate for the H1N test at a speed,
measured by RPM or power input frequency (Hz), no lower than the
speed used in the A2 test. The compressor shall operate
at the same heating minimum speed, measured by RPM or power input
frequency (Hz), for the H01, H1C1, and
H11 Tests. Determine the heating intermediate compressor
speed cited in Table 13 using the heating mode full and minimum
compressors speeds and:
Heating intermediate speed
[GRAPHIC] [TIFF OMITTED] TP24AU16.003
Where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
b. If the H12 test is conducted, set the 47 [deg]F
capacity and power input values used for calculation of HSPF equal
to the measured values for that test:
Qhcalck=2(47) = Qhk=2(47);
Ehcalck=2(47) = Ehk=2(47)
Where:
[[Page 58208]]
Qhcalck=2(47) and Ehcalck=2(47) are the
capacity and power input representing full-speed operation at 47
[deg]F for the HSPF calculations,
Qhk=2(47) is the capacity measured in the H12
test, and
Ehk=2(47) is the power input measured in the
H12 test.
Evaluate the quantities Qhk=2(47) and from
Ehk=2(47) according to section 3.7.
Otherwise, if the H1N test is conducted using the
same compressor speed (RPM or power input frequency) as the
H32 test, set the 47 [deg]F capacity and power input
values used for calculation of HSPF equal to the measured values for
that test:
Qhcalck=2(47) = Qhk=N(47); Ehcalck=2(47) =
Ehk=N(47)
Where:
Qhcalck=2(47) and Ehcalck=2(47) are the
capacity and power input representing full-speed operation at 47
[deg]F for the HSPF calculations,
Qhk=N(47) is the capacity measured in the H1N test, and
Ehk=N(47) is the power input measured in the H1N test.
Evaluate the quantities Qhk=N(47) and from
Ehk=N(47) according to section 3.7.
Otherwise (if no high temperature test is conducted using the
same speed (RPM or power input frequency) as the H32
test), calculate the 47 [deg]F capacity and power input values used
for calculation of HSPF as follows:
Qhcalck=2(47) = Qhk=2(17) * (1 + 30 [deg]F *
CSF);
Ehcalck=2(47) = Ehk=2(17) * (1 + 30 [deg]F *
PSF)
Where:
Qhcalck=2(47) and Ehcalck=2(47) are the
capacity and power input representing full-speed operation at 47
[deg]F for the HSPF calculations,
Qhk=2(17) is the capacity measured in the H32
test,
Ehk=2(17) is the power input measured in the
H32 test,
CSF is the capacity slope factor, equal to 0.0204/[deg]F for split
systems and 0.0262/[deg]F for single-package systems, and
PSF is the Power Slope Factor, equal to 0.00455/[deg]F.
c. If the H22 test is not done, use the following
equations to approximate the capacity and electrical power at the
H22 test conditions:
Qhk=2(35) = 0.90 * {Qhk=2(17) + 0.6 *
[Qhcalck=2(47) - Qhk=2(17)]{time}
Ehk=2(35) = 0.985 * {Ehk=2(17) + 0.6 *
[Ehcalck=2(47) - Ehk=2(17)]{time}
Where:
Qhcalck=2(47) and Ehcalck=2(47) are the
capacity and power input representing full-speed operation at 47
[deg]F for the HSPF calculations, calculated as described in section
b above.
Qhk=2(17) and Ehk=2(17) are the capacity and
power input measured in the H32 test.
d. Determine the quantities Qhk=2(17) and
Ehk=2(17) from the H32 test,
determine the quantities Qhk=2(5) and
Ehk=2(5) and Ehk=2(5)
from the H42 test, and evaluate all four according to
section 3.10.
Table 13--Heating Mode Test Conditions for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor speed Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady).......... 70 60\(max)\ 62 56.5 Heating Minimum......... Heating Minimum.\1\
H12 test (optional, steady).......... 70 60\(max)\ 47 43 Heating Full \4\........ Heating Full-Load.\3\
H11 test (required, steady).......... 70 60\(max)\ 47 43 Heating Minimum......... Heating Minimum.\1\
H1N test (required, steady).......... 70 60\(max)\ 47 43 Heating Full............ Heating Full-Load.\3\
H1C1 test (optional, cyclic)......... 70 60\(max)\ 47 43 Heating Minimum......... (\2\)
H22 test (optional).................. 70 60\(max)\ 35 33 Heating Full \4\........ Heating Full-Load.\3\
H2V test (required).................. 70 60\(max)\ 35 33 Heating Intermediate.... Heating
Intermediate.\5\
H32 test (required, steady).......... 70 60\(max)\ 17 15 Heating Full \4\........ Heating Full-Load.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17[emsp14][deg]F ambient temperature. The H12 test is not
needed if the H1N test uses this same compressor speed.
\5\ Defined in section 3.1.4.6 of this appendix.
* * * * *
3.11.1 If Using the Outdoor Air Enthalpy Method as the Secondary Test
Method
a. For all cooling mode and heating mode tests, first conduct a
test without the outdoor air-side test apparatus described in
section 2.10.1 of this appendix connected to the outdoor unit
(``non-ducted'' test).
b. For the first section 3.2 steady-state cooling mode test and
the first section 3.6 steady-state heating mode test, conduct a
second test in which the outdoor-side apparatus is connected
(``ducted'' test). No other cooling mode or heating mode tests
require the ducted test so long as the unit operates the outdoor fan
during all cooling mode steady-state tests at the same speed and all
heating mode steady-state tests at the same speed. If using more
than one outdoor fan speed for the cooling mode steady-state tests,
however, conduct the ducted test for each cooling mode test where a
different fan speed is first used. This same requirement applies for
the heating mode tests.
* * * * *
3.11.1.1 Non-Ducted Test
a. For the non-ducted test, connect the indoor air-side test
apparatus to the indoor coil; do not connect the outdoor air-side
test apparatus. Allow the test room reconditioning apparatus and the
unit being tested to operate for at least one hour. After attaining
equilibrium conditions, measure the following quantities at equal
intervals that span 5 minutes or less:
(1) The section 2.10.1 evaporator and condenser temperatures or
pressures;
(2) Parameters required according to the indoor air enthalpy
method.
Continue these measurements until a 30-minute period (e.g.,
seven consecutive 5-minute samples) is obtained where the Table 8 or
Table 15, whichever applies, test tolerances are satisfied.
b. For cases where a ducted test is not required per section
3.11.1.b of this appendix, the non-ducted test constitutes the
``official'' test for which validity is not based on comparison with
a secondary test.
c. For cases where a ducted test is required per section
3.11.1.b of this appendix, the following conditions must be met for
the non-ducted test to constitute a valid ``official'' test:
(1) The energy balance specified in section 3.1.1 of this
appendix is achieved for the ducted test (i.e., compare the
capacities determined using the indoor air enthalpy method and the
outdoor air enthalpy method).
(2) The capacities determined using the indoor air enthalpy
method from the ducted and non-ducted tests must agree within 2.0
percent.
3.11.1.2 Ducted Test
a. The test conditions and tolerances for the ducted test are
the same as specified for the official test.
b. After collecting 30 minutes of steady-state data during the
non-ducted test, connect the outdoor air-side test apparatus to the
unit for the ducted test. Adjust the exhaust fan of the outdoor
airflow measuring apparatus until averages for the evaporator and
condenser temperatures, or the saturated temperatures corresponding
to the measured pressures, agree within 0.5[emsp14][deg]F of the averages achieved during the non-
ducted test. Calculate the averages for the ducted test using five
or more consecutive readings taken
[[Page 58209]]
at one minute intervals. Make these consecutive readings after re-
establishing equilibrium conditions.
c. During the ducted test, at one minute intervals, measure the
parameters required according to the indoor air enthalpy method and
the outdoor air enthalpy method.
d. For cooling mode ducted tests, calculate capacity based on
outdoor air-enthalpy measurements as specified in sections 7.3.3.2
and 7.3.3.3 of ASHRAE 37-2009 (incorporated by reference, see Sec.
430.3). For heating mode ducted tests, calculate heating capacity
based on outdoor air-enthalpy measurements as specified in sections
7.3.4.2 and 7.3.3.4.3 of the same ASHRAE Standard. Adjust the
outdoor-side capacity according to section 7.3.3.4 of ASHRAE 37-2009
to account for line losses when testing split systems.
* * * * *
* * * * *
3.13.2 This test determines the off mode average power rating
for central air conditioners and heat pumps for which ambient
temperature can affect the measurement of crankcase heater power.
* * * * *
b. Configure Controls: Position a temperature sensor to measure
the outdoor dry-bulb temperature in the air between 2 and 6 inches
from the crankcase heater control temperature sensor or, if no such
temperature sensor exists, position it in the air between 2 and 6
inches from the crankcase heater. Utilize the temperature
measurements from this sensor for this portion of the test
procedure. Configure the controls of the central air conditioner or
heat pump so that it operates as if connected to a building
thermostat that is set to the OFF position. Use a compatible
building thermostat if necessary to achieve this configuration.
Conduct the test after completion of the B, B1, or
B2 test. Alternatively, start the test when the outdoor
dry-bulb temperature is at 82[emsp14][deg]F and the temperature of
the compressor shell (or temperature of each compressor's shell if
there is more than one compressor) is at least 81[emsp14][deg]F.
Then adjust the outdoor temperature and achieve an outdoor dry-bulb
temperature of 72[emsp14][deg]F. If the unit's compressor has no
sound blanket, wait at least 4 hours after the outdoor temperature
reaches 72[emsp14][deg]F. Otherwise, wait at least 8 hours after the
outdoor temperature reaches 72[emsp14][deg]F. Maintain this
temperature within +/-2[emsp14][deg]F while the compressor
temperature equilibrates and while making the power measurement, as
described in section 3.13.2.c of this appendix.
* * * * *
d. Reduce outdoor temperature: Approach the target outdoor dry-
bulb temperature by adjusting the outdoor temperature. This target
temperature is five degrees Fahrenheit less than the temperature
certified by the manufacturer as the temperature at which the
crankcase heater turns on. If the unit's compressor has no sound
blanket, wait at least 4 hours after the outdoor temperature reaches
the target temperature. Otherwise, wait at least 8 hours after the
outdoor temperature reaches the target temperature. Maintain the
target temperature within +/-2[emsp14][deg]F while the compressor
temperature equilibrates and while making the power measurement, as
described in section 3.13.2.e of this appendix.
4.1 * * *
* * * * *
4.1.3 SEER Calculations for an Air Conditioner or Heat Pump Having a
Two-Capacity Compressor
* * * * *
The calculation of Equation 4.1-1 quantities
qc(Tj)/N and ec(Tj)/N
differs depending on whether the test unit would operate at low
capacity (section 4.1.3.1 of this appendix), cycle between low and
high capacity (section 4.1.3.2 of this appendix), or operate at high
capacity (sections 4.1.3.3 and 4.1.3.4 of this appendix) in
responding to the building load. For units that lock out low
capacity operation at higher outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations are used. Use Equation 4.1-2 to calculate the building
load, BL(Tj), for each temperature bin.
* * * * *
4.1.4.2 Unit operates at an intermediate compressor speed (k=i)
in order to match the building cooling load at temperature
Tj,Qc\k=1\(Tj) j)
c\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.004
Where:
Qc\k=i\(Tj) = BL(Tj), the space
cooling capacity delivered by the unit in matching the building load
at temperature Tj, Btu/h. The matching occurs with the
unit operating at compressor speed k = i.
[GRAPHIC] [TIFF OMITTED] TP24AU16.005
EER\k=i\(Tj), the steady-state energy efficiency ratio of
the test unit when operating at a compressor speed of k = i and
temperature Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. For each temperature bin where the
unit operates at an intermediate compressor speed, determine the
energy efficiency ratio EER\k=i\(Tj) using the following
equations,
For each temperature bin where Qc\k=1\(Tj)
j) c\k=v\(Tj),
[GRAPHIC] [TIFF OMITTED] TP24AU16.006
For each temperature bin where
QcK=v(Tj) <=BL(Tj)
cK=2(Tj),
[[Page 58210]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.007
Where:
EER\k=1\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at minimum compressor speed and
temperature Tj, Btu/h per W, calculated using capacity
Qc\k=1\(Tj) calculated using Equation 4.1.4-1
and electrical power consumption Ec\k=1\(Tj)
calculated using Equation 4.1.4-2;
EER\k=v\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at intermediate compressor speed and
temperature Tj, Btu/h per W, calculated using capacity
Qc\k=v\(Tj) calculated using Equation 4.1.4-3
and electrical power consumption Ec\k=v\(Tj)
calculated using Equation 4.1.4-4;
EER\k=2\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at full compressor speed and
temperature Tj, Btu/h per W, calculated using capacity
Qc\k=2\(Tj) and electrical power consumption
Ec\k=2\(Tj), both calculated as described in
section 4.1.4; and
BL(Tj) is the building cooling load at temperature
Tj, Btu/h.
* * * * *
4.2 * * *
* * * * *
b. For a section 3.6.2 single-speed heat pump or a two-capacity
heat pump not covered by item d, Qh\k\(47) =
Qh\k=2\(47), the space heating capacity determined from
the H1 or H12 test.
c. For a variable-speed heat pump, Qh\k\(47) =
Qh\k=N\(47), the space heating capacity determined from
the H1N test.
d. For two-capacity, northern heat pumps (see section 1.2 of
this appendix, Definitions), Qh\k\h(47) =
Q\k=1\h(47), the space heating capacity determined from
the H11 test.
For all heat pumps, HSPF accounts for * * *
* * * * *
4.2.3 Additional Steps for Calculating the HSPF of a Heat Pump Having a
Two-Capacity Compressor
The calculation of the Equation 4.2-1 quantities differ
depending upon whether the heat pump would operate at low capacity
(section 4.2.3.1 of this appendix), cycle between low and high
capacity (section 4.2.3.2 of this appendix), or operate at high
capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in
responding to the building load. For heat pumps that lock out low
capacity operation at low outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations can be selected.
* * * * *
4.2.4 * * *
* * * * *
Evaluate the space heating capacity,
Qh\k=2\(Tj), and electrical power consumption,
Eh\k=2\(Tj), of the heat pump when operating
at full compressor speed and outdoor temperature Tj by
solving Equations 4.2.2-3 and 4.2.2-4, respectively, for k=2. For
Equation 4.2.2-3, use Qhcalc\k=2\(47) to represent
Qh\k=2\(47), and for Equation 4.2.2-4, use
Ehcalc\k=2\(47) to represent Ehcalc\k=2\(47)--
evaluate Qhcalc\k=2\(47) and Ehcalc\k=2\(47)
as specified in section 3.6.4b of this appendix. * * *
* * * * *
4.2.4.2 Heat pump operates at an intermediate compressor speed
(k=i) in order to match the building heating load at a temperature
Tj, Qh\k=1\(Tj) j)
h\k=2\(Tj). Calculate
[GRAPHIC] [TIFF OMITTED] TP24AU16.008
and [delta](Tj) is evaluated using Equation 4.2.3-3
while,
Qh\k=i\(Tj) = BL(Tj), the space
heating capacity delivered by the unit in matching the building load
at temperature (Tj), Btu/h. The matching occurs with the
heat pump operating at compressor speed k=i.
COP\k=i\(Tj) = the steady-state coefficient of
performance of the heat pump when operating at compressor speed k=i
and temperature Tj, dimensionless.
For each temperature bin where the heat pump operates at an
intermediate compressor speed, determine COP\k=i\(Tj)
using the following equations,
For each temperature bin where Qh\k=1\(Tj)
j) h\k=v\(Tj),
[[Page 58211]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.009
Where:
COPh\k=1\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at minimum compressor
speed and temperature Tj, dimensionless, calculated using capacity
Qh\k=1\(Tj) calculated using Equation 4.2.4-1
and electrical power consumption Eh\k=1\(Tj)
calculated using Equation 4.2.4-2;
COPh\k=v\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at intermediate
compressor speed and temperature Tj, dimensionless, calculated using
capacity Qh\k=v\(Tj) calculated using Equation
4.2.4-3 and electrical power consumption
Eh\k=v\(Tj) calculated using Equation 4.2.4-4;
COPh\k=2\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at full compressor
speed and temperature Tj, dimensionless, calculated using capacity
Qh\k=2\(Tj) and electrical power consumption
Eh\k=2\(Tj), both calculated as described in
section 4.2.4; and
BL(Tj) is the building heating load at temperature
Tj, Btu/h.
0
9. Add appendix M1 to subpart B of part 430 to read as follows:
Appendix M1 to Subpart B of Part 430--Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps
Prior to January 1, 2023, any representations, including
compliance certifications, made with respect to the energy use,
power, or efficiency of central air conditioners and central air
conditioning heat pumps must be based on the results of testing
pursuant to Appendix M of this subpart.
On or after January 1, 2023, any representations, including
compliance certifications, made with respect to the energy use,
power, or efficiency of central air conditioners and central air
conditioning heat pumps must be based on the results of testing
pursuant to this appendix.
1. Scope and Definitions
1.1 Scope
This test procedure provides a method of determining SEER, EER,
HSPF and PW,OFF for central air conditioners and central
air conditioning heat pumps including the following categories:
(a) Split-system air conditioners, including single-split, multi-
head mini-split, multi-split (including VRF), and multi-circuit
systems
(b) Split-system heat pumps, including single-split, multi-head
mini-split, multi-split (including VRF), and multi-circuit systems
(c) Single-package air conditioners
(d) Single-package heat pumps
(e) Small-duct, high-velocity systems (including VRF)
(f) Space-constrained products--air conditioners
(g) Space-constrained products--heat pumps
For the purposes of this appendix, the Department of Energy
incorporates by reference specific sections of several industry
standards, as listed in Sec. 430.3. In cases where there is a
conflict, the language of the test procedure in this appendix takes
precedence over the incorporated standards.
All section references refer to sections within this appendix
unless otherwise stated.
1.2 Definitions
Airflow-control settings are programmed or wired control system
configurations that control a fan to achieve discrete, differing
ranges of airflow--often designated for performing a specific
function (e.g., cooling, heating, or constant circulation)--without
manual adjustment other than interaction with a user-operable
control (i.e., a thermostat) that meets the manufacturer
specifications for installed-use. For the purposes of this appendix,
manufacturer specifications for installed-use are those found in the
product literature shipped with the unit.
Air sampling device is an assembly consisting of a manifold with
several branch tubes with multiple sampling holes that draws an air
sample from a critical location from the unit under test (e.g.
indoor air inlet, indoor air outlet, outdoor air inlet, etc.).
Airflow prevention device denotes a device that prevents airflow
via natural convection by mechanical means, such as an air damper
box, or by means of changes in duct height, such as an upturned
duct.
Aspirating psychrometer is a piece of equipment with a monitored
airflow section that draws uniform airflow through the measurement
section and has probes for measurement of air temperature and
humidity.
Blower coil indoor unit means an indoor unit either with an
indoor blower housed with the coil or with a separate designated air
mover such as a furnace or a modular blower (as defined in appendix
AA to the subpart).
Blower coil system refers to a split system that includes one or
more blower coil indoor units.
Cased coil means a coil-only indoor unit with external
cabinetry.
Ceiling-mount blower coil system means a split-system air
conditioner or heat pump for which the outdoor unit has a certified
cooling capacity less than or equal to 36,000 Btu/h and the indoor
unit is shipped with manufacturer-supplied installation instructions
that specify to secure the indoor unit only to the ceiling of the
conditioned space, with return air directly to the bottom of the
unit (without ductwork), having an installed height no more than 12
inches (not including condensate drain lines) and depth (in the
direction of airflow) of no more than 30 inches, with supply air
discharged horizontally.
Coefficient of Performance (COP) means the ratio of the average
rate of space heating delivered to the average rate of electrical
energy consumed by the heat pump. Determine these rate quantities
from a single test or, if derived via interpolation, determine at a
single set of operating conditions. COP is a dimensionless quantity.
When determined for a ducted coil-only system, COP must be
calculated using the default values for heat output and power input
of a fan motor specified in sections 3.7 and 3.9.1 of this appendix.
Coil-only indoor unit means an indoor unit that is distributed
in commerce without an indoor blower or separate designated air
mover. A coil-only indoor unit installed in the field relies on a
separately-installed furnace or a modular blower for indoor air
movement.
Coil-only system means a system that includes only (one or more)
coil-only indoor units.
Condensing unit removes the heat absorbed by the refrigerant to
transfer it to the outside environment and consists of an outdoor
coil, compressor(s), and air moving device.
Constant-air-volume-rate indoor blower means a fan that varies
its operating speed to provide a fixed air-volume-rate from a ducted
system.
Continuously recorded, when referring to a dry bulb measurement,
dry bulb temperature used for test room control, wet bulb
temperature, dew point temperature, or relative humidity
measurements, means that the specified value must be sampled at
regular intervals that are equal to or less than 15 seconds.
Cooling load factor (CLF) means the ratio having as its
numerator the total cooling delivered during a cyclic operating
interval
[[Page 58212]]
consisting of one ON period and one OFF period, and as its
denominator the total cooling that would be delivered, given the
same ambient conditions, had the unit operated continuously at its
steady-state, space-cooling capacity for the same total time (ON +
OFF) interval.
Crankcase heater means any electrically powered device or
mechanism for intentionally generating heat within and/or around the
compressor sump volume. Crankcase heater control may be achieved
using a timer or may be based on a change in temperature or some
other measurable parameter, such that the crankcase heater is not
required to operate continuously. A crankcase heater without
controls operates continuously when the compressor is not operating.
Cyclic Test means a test where the unit's compressor is cycled
on and off for specific time intervals. A cyclic test provides half
the information needed to calculate a degradation coefficient.
Damper box means a short section of duct having an air damper
that meets the performance requirements of section 2.5.7 of this
appendix.
Degradation coefficient (CD) means a parameter used
in calculating the part load factor. The degradation coefficient for
cooling is denoted by CD\c\. The degradation coefficient
for heating is denoted by CD\h\.
Demand-defrost control system means a system that defrosts the
heat pump outdoor coil-only when measuring a predetermined
degradation of performance. The heat pump's controls either:
(1) Monitor one or more parameters that always vary with the
amount of frost accumulated on the outdoor coil (e.g., coil to air
differential temperature, coil differential air pressure, outdoor
fan power or current, optical sensors) at least once for every ten
minutes of compressor ON-time when space heating or
(2) Operate as a feedback system that measures the length of the
defrost period and adjusts defrost frequency accordingly. In all
cases, when the frost parameter(s) reaches a predetermined value,
the system initiates a defrost. In a demand-defrost control system,
defrosts are terminated based on monitoring a parameter(s) that
indicates that frost has been eliminated from the coil. (Note:
Systems that vary defrost intervals according to outdoor dry-bulb
temperature are not demand-defrost systems.) A demand-defrost
control system, which otherwise meets the requirements, may allow
time-initiated defrosts if, and only if, such defrosts occur after 6
hours of compressor operating time.
Design heating requirement (DHR) predicts the space heating load
of a residence when subjected to outdoor design conditions.
Estimates for the minimum and maximum DHR are provided for six
generalized U.S. climatic regions in section 4.2 of this appendix.
Dry-coil tests are cooling mode tests where the wet-bulb
temperature of the air supplied to the indoor unit is maintained low
enough that no condensate forms on the evaporator coil.
Ducted system means an air conditioner or heat pump that is
designed to be permanently installed equipment and delivers
conditioned air to the indoor space through a duct(s). The air
conditioner or heat pump may be either a split-system or a single-
package unit.
Energy efficiency ratio (EER) means the ratio of the average
rate of space cooling delivered to the average rate of electrical
energy consumed by the air conditioner or heat pump. Determine these
rate quantities must be determined from a single test or, if derived
via interpolation, determine at a single set of operating
conditions. EER is expressed in units of
[GRAPHIC] [TIFF OMITTED] TP24AU16.010
When determined for a ducted coil-only system, EER must include,
from this appendix, the section 3.3 and 3.5.1 default values for the
heat output and power input of a fan motor.
Evaporator coil means an assembly that absorbs heat from an
enclosed space and transfers the heat to a refrigerant.
Heat pump means a kind of central air conditioner that utilizes
an indoor conditioning coil, compressor, and refrigerant-to-outdoor
air heat exchanger to provide air heating, and may also provide air
cooling, air dehumidifying, air humidifying, air circulating, and
air cleaning.
Heat pump having a heat comfort controller means a heat pump
with controls that can regulate the operation of the electric
resistance elements to assure that the air temperature leaving the
indoor section does not fall below a specified temperature. Heat
pumps that actively regulate the rate of electric resistance heating
when operating below the balance point (as the result of a second
stage call from the thermostat) but do not operate to maintain a
minimum delivery temperature are not considered as having a heat
comfort controller.
Heating load factor (HLF) means the ratio having as its
numerator the total heating delivered during a cyclic operating
interval consisting of one ON period and one OFF period, and its
denominator the heating capacity measured at the same test
conditions used for the cyclic test, multiplied by the total time
interval (ON plus OFF) of the cyclic-test.
Heating season means the months of the year that require
heating, e.g., typically, and roughly, October through April.
Heating seasonal performance factor (HSPF) means the total space
heating required during the heating season, expressed in Btu,
divided by the total electrical energy consumed by the heat pump
system during the same season, expressed in watt-hours. The HSPF
used to evaluate compliance with 10 CFR 430.32(c) is based on Region
IV and the sampling plan stated in 10 CFR 429.16(a).
Independent coil manufacturer (ICM) means a manufacturer that
manufactures indoor units but does not manufacture single-package
units or outdoor units.
Indoor unit means a separate assembly of a split system that
includes--
(1) An arrangement of refrigerant-to-air heat transfer coil(s)
for transfer of heat between the refrigerant and the indoor air,
(2) A condensate drain pan, and may or may not include
(3) Sheet metal or plastic parts not part of external cabinetry
to direct/route airflow over the coil(s),
(4) A cooling mode expansion device,
(5) External cabinetry, and
(6) An integrated indoor blower (i.e. a device to move air
including its associated motor). A separate designated air mover
that may be a furnace or a modular blower (as defined in appendix AA
to the subpart) may be considered to be part of the indoor unit. A
service coil is not an indoor unit.
Low-static blower coil system means a ducted multi-split or
multi-head mini-split system for which all indoor units produce
greater than 0.01 in. wc. and a maximum of 0.35 in. wc. external
static pressure when operated at the cooling full-load air volume
rate not exceeding 400 cfm per rated ton of cooling.
Mid-static blower coil system means a ducted multi-split or
multi-head mini-split system for which all indoor units produce
greater than 0.20 in. wc. and a maximum of 0.65 in. wc. when
operated at the cooling full-load air volume rate not exceeding 400
cfm per rated ton of cooling.
Minimum-speed-limiting variable-speed heat pump means a heat
pump for which the compressor speed (represented by revolutions per
minute or motor power input frequency) is higher than its value for
operation in a 47 [deg]F ambient temperature for any bin temperature
Tj for which the calculated heating load is less than the
calculated intermediate-speed capacity.
Mobile home blower coil system means a split system that
contains an outdoor unit and an indoor unit that meet the following
criteria:
(1) Both the indoor and outdoor unit are shipped with
manufacturer-supplied installation instructions that specify
installation only in a mobile home with the home and equipment
complying with HUD Manufactured Home Construction Safety Standard 24
CFR part 3280;
(2) The indoor unit cannot exceed 0.40 in. wc. when operated at
the cooling full-load air volume rate not exceeding 400 cfm per
rated ton of cooling; and
(3)The indoor and outdoor unit each must bear a label in at
least \1/4\ inch font that reads ``For installation only in HUD
manufactured home per Construction Safety Standard 24 CFR part
3280.''
Mobile home coil-only system means a coil-only split system that
includes an outdoor unit and coil-only indoor unit that meet the
following criteria:
(1) The outdoor unit is shipped with manufacturer-supplied
installation instructions that specify installation only for mobile
homes that comply with HUD Manufactured Home Construction Safety
Standard 24 CFR part 3280,
(2) The coil-only indoor unit is shipped with manufacturer-
supplied installation instructions that specify installation only in
a mobile home furnace, modular blower, or designated air mover that
complies with HUD Manufactured Home Construction Safety Standard 24
CFR part 3280, and
(3) The coil-only indoor unit and outdoor unit each has a label
in at least \1/4\ inch font
[[Page 58213]]
that reads ``For installation only in HUD manufactured home per
Construction Safety Standard 24 CFR part 3280.''
Multi-head mini-split system means a split system that has one
outdoor unit and that has two or more indoor units connected with a
single refrigeration circuit. The indoor units operate in unison in
response to a single indoor thermostat.
Multiple-circuit (or multi-circuit) system means a split system
that has one outdoor unit and that has two or more indoor units
installed on two or more refrigeration circuits such that each
refrigeration circuit serves a compressor and one and only one
indoor unit, and refrigerant is not shared from circuit to circuit.
Multiple-split (or multi-split) system means a split system that
has one outdoor unit and two or more coil-only indoor units and/or
blower coil indoor units connected with a single refrigerant
circuit. The indoor units operate independently and can condition
multiple zones in response to at least two indoor thermostats or
temperature sensors. The outdoor unit operates in response to
independent operation of the indoor units based on control input of
multiple indoor thermostats or temperature sensors, and/or based on
refrigeration circuit sensor input (e.g., suction pressure).
Nominal capacity means the capacity that is claimed by the
manufacturer on the product name plate. Nominal cooling capacity is
approximate to the air conditioner cooling capacity tested at A or
A2 condition. Nominal heating capacity is approximate to the heat
pump heating capacity tested in the H1N test.
Non-ducted indoor unit means an indoor unit that is designed to
be permanently installed, mounted on room walls and/or ceilings, and
that directly heats or cools air within the conditioned space.
Normalized Gross Indoor Fin Surface (NGIFS) means the gross fin
surface area of the indoor unit coil divided by the cooling capacity
measured for the A or A2 Test, whichever applies.
Off-mode power consumption means the power consumption when the
unit is connected to its main power source but is neither providing
cooling nor heating to the building it serves.
Off-mode season means, for central air conditioners other than
heat pumps, the shoulder season and the entire heating season; and
for heat pumps, the shoulder season only.
Outdoor unit means a separate assembly of a split system that
transfers heat between the refrigerant and the outdoor air, and
consists of an outdoor coil, compressor(s), an air moving device,
and in addition for heat pumps, may include a heating mode expansion
device, reversing valve, and/or defrost controls.
Outdoor unit manufacturer (OUM) means a manufacturer of single-
package units, outdoor units, and/or both indoor units and outdoor
units.
Part-load factor (PLF) means the ratio of the cyclic EER (or COP
for heating) to the steady-state EER (or COP), where both EERs (or
COPs) are determined based on operation at the same ambient
conditions.
Seasonal energy efficiency ratio (SEER) means the total heat
removed from the conditioned space during the annual cooling season,
expressed in Btu's, divided by the total electrical energy consumed
by the central air conditioner or heat pump during the same season,
expressed in watt-hours.
Service coil means an arrangement of refrigerant-to-air heat
transfer coil(s), condensate drain pan, sheet metal or plastic parts
to direct/route airflow over the coil(s), which may or may not
include external cabinetry and/or a cooling mode expansion device,
distributed in commerce solely for replacing an uncased coil or
cased coil that has already been placed into service, and that has
been labeled ``for indoor coil replacement only'' on the nameplate
and in manufacturer technical and product literature. The model
number for any service coil must include some mechanism (e.g., an
additional letter or number) for differentiating a service coil from
a coil intended for an indoor unit.
Shoulder season means the months of the year in between those
months that require cooling and those months that require heating,
e.g., typically, and roughly, April through May, and September
through October.
Single-package unit means any central air conditioner or heat
pump that has all major assemblies enclosed in one cabinet.
Single-split system means a split system that has one outdoor
unit and one indoor unit connected with a single refrigeration
circuit.
Small-duct, high-velocity system means a split system for which
all indoor units are blower coil indoor units that produce at least
1.2 inches (of water column) of external static pressure when
operated at the full-load air volume rate certified by the
manufacturer of at least 220 scfm per rated ton of cooling.
Split system means any central air conditioner or heat pump that
has at least two separate assemblies that are connected with
refrigerant piping when installed. One of these assemblies includes
an indoor coil that exchanges heat with the indoor air to provide
heating or cooling, while one of the others includes an outdoor coil
that exchanges heat with the outdoor air. Split systems may be
either blower coil systems or coil-only systems.
Standard Air means dry air having a mass density of 0.075 lb/
ft\3\.
Steady-state test means a test where the test conditions are
regulated to remain as constant as possible while the unit operates
continuously in the same mode.
Temperature bin means the 5[emsp14][deg]F increments that are
used to partition the outdoor dry-bulb temperature ranges of the
cooling (>=65[emsp14][deg]F) and heating (<65[emsp14][deg]F)
seasons.
Test condition tolerance means the maximum permissible
difference between the average value of the measured test parameter
and the specified test condition.
Test operating tolerance means the maximum permissible range
that a measurement may vary over the specified test interval. The
difference between the maximum and minimum sampled values must be
less than or equal to the specified test operating tolerance.
Tested combination means a multi-head mini-split, multi-split,
or multi-circuit system having the following features:
(1) The system consists of one outdoor unit with one or more
compressors matched with between two and five indoor units;
(2) The indoor units must:
(i) Collectively, have a nominal cooling capacity greater than
or equal to 95 percent and less than or equal to 105 percent of the
nominal cooling capacity of the outdoor unit;
(ii) Each represent the highest sales volume model family, if
this is possible while meeting all the requirements of this section.
If this is not possible, one or more of the indoor units may
represent another indoor model family in order that all the other
requirements of this section are met.
(iii) Individually not have a nominal cooling capacity greater
than 50 percent of the nominal cooling capacity of the outdoor unit,
unless the nominal cooling capacity of the outdoor unit is 24,000
Btu/h or less;
(iv) Operate at fan speeds consistent with manufacturer's
specifications; and
(v) All be subject to the same minimum external static pressure
requirement while able to produce the same external static pressure
at the exit of each outlet plenum when connected in a manifold
configuration as required by the test procedure.
(3) Where referenced, ``nominal cooling capacity'' means, for
indoor units, the highest cooling capacity listed in published
product literature for 95[emsp14][deg]F outdoor dry bulb temperature
and 80[emsp14][deg]F dry bulb, 67[emsp14][deg]F wet bulb indoor
conditions, and for outdoor units, the lowest cooling capacity
listed in published product literature for these conditions. If
incomplete or no operating conditions are published, use the highest
(for indoor units) or lowest (for outdoor units) such cooling
capacity available for sale.
Time-adaptive defrost control system is a demand-defrost control
system that measures the length of the prior defrost period(s) and
uses that information to automatically determine when to initiate
the next defrost cycle.
Time-temperature defrost control systems initiate or evaluate
initiating a defrost cycle only when a predetermined cumulative
compressor ON-time is obtained. This predetermined ON-time is
generally a fixed value (e.g., 30, 45, 90 minutes) although it may
vary based on the measured outdoor dry-bulb temperature. The ON-time
counter accumulates if controller measurements (e.g., outdoor
temperature, evaporator temperature) indicate that frost formation
conditions are present, and it is reset/remains at zero at all other
times. In one application of the control scheme, a defrost is
initiated whenever the counter time equals the predetermined ON-
time. The counter is reset when the defrost cycle is completed.
In a second application of the control scheme, one or more
parameters are measured (e.g., air and/or refrigerant temperatures)
at the predetermined, cumulative, compressor ON-time. A defrost is
initiated only if the measured parameter(s) falls within a
predetermined range. The ON-time counter is reset regardless of
whether or not a defrost is initiated. If systems of this second
type use cumulative ON-time
[[Page 58214]]
intervals of 10 minutes or less, then the heat pump may qualify as
having a demand defrost control system (see definition).
Triple-capacity, northern heat pump means a heat pump that
provides two stages of cooling and three stages of heating. The two
common stages for both the cooling and heating modes are the low
capacity stage and the high capacity stage. The additional heating
mode stage is the booster capacity stage, which offers the highest
heating capacity output for a given set of ambient operating
conditions.
Triple-split system means a split system that is composed of
three separate assemblies: An outdoor fan coil section, a blower
coil indoor unit, and an indoor compressor section.
Two-capacity (or two-stage) compressor system means a central
air conditioner or heat pump that has a compressor or a group of
compressors operating with only two stages of capacity. For such
systems, low capacity means the compressor(s) operating at low
stage, or at low load test conditions. The low compressor stage that
operates for heating mode tests may be the same or different from
the low compressor stage that operates for cooling mode tests. For
such systems, high capacity means the compressor(s) operating at
high stage, or at full load test conditions.
Two-capacity, northern heat pump means a heat pump that has a
factory or field-selectable lock-out feature to prevent space
cooling at high-capacity. Two-capacity heat pumps having this
feature will typically have two sets of ratings, one with the
feature disabled and one with the feature enabled. The heat pump is
a two-capacity northern heat pump only when this feature is enabled
at all times. The certified indoor coil model number must reflect
whether the ratings pertain to the lockout enabled option via the
inclusion of an extra identifier, such as ``+LO''. When testing as a
two-capacity, northern heat pump, the lockout feature must remain
enabled for all tests.
Uncased coil means a coil-only indoor unit without external
cabinetry.
Variable refrigerant flow (VRF) system means a multi-split
system with at least three compressor capacity stages, distributing
refrigerant through a piping network to multiple indoor blower coil
units each capable of individual zone temperature control, through
proprietary zone temperature control devices and a common
communications network. Note: Single-phase VRF systems less than
65,000 Btu/h are central air conditioners and central air
conditioning heat pumps.
Variable-speed compressor system means a central air conditioner
or heat pump that has a compressor that uses a variable-speed drive
to vary the compressor speed to achieve variable capacities.
Wall-mount blower coil system means a split-system air
conditioner or heat pump for which the outdoor unit has a certified
cooling capacity less than or equal to 36,000 Btu/h and the indoor
unit is shipped with manufacturer-supplied installation instructions
that specify to secure the back side of the unit only to a wall
within the conditioned space, with the capability of front air
return (without ductwork) and not capable of horizontal airflow,
having a height no more than 45 inches, a depth of no more than 22
inches (including tubing connections), and a width no more than 24
inches (in the direction parallel to the wall).
Wet-coil test means a test conducted at test conditions that
typically cause water vapor to condense on the test unit evaporator
coil.
2. Testing Overview and Conditions
(A) Test VRF systems using AHRI 1230-2010 (incorporated by
reference, see Sec. 430.3) and appendix M. Where AHRI 1230-2010
refers to the appendix C therein substitute the provisions of this
appendix. In cases where there is a conflict, the language of the
test procedure in this appendix takes precedence over AHRI 1230-
2010.
For definitions use section 1 of appendix M and section 3 of
AHRI 1230-2010 (incorporated by reference, see Sec. 430.3). For
rounding requirements, refer to Sec. 430.23(m). For determination
of certified ratings, refer to Sec. 429.16 of this chapter.
For test room requirements, refer to section 2.1 of this
appendix. For test unit installation requirements refer to sections
2.2.a, 2.2.b, 2.2.c, 2.2.1, 2.2.2, 2.2.3.a, 2.2.3.c, 2.2.4, 2.2.5,
and 2.4 to 2.12 of this appendix, and sections 5.1.3 and 5.1.4 of
AHRI 1230-2010. The ``manufacturer's published instructions,'' as
stated in section 8.2 of ANSI/ASHRAE 37-2009 (incorporated by
reference, see Sec. 430.3) and ``manufacturer's installation
instructions'' discussed in this appendix mean the manufacturer's
installation instructions that come packaged with or appear in the
labels applied to the unit. This does not include online manuals.
Installation instructions that appear in the labels applied to the
unit take precedence over installation instructions that are shipped
with the unit.
For general requirements for the test procedure, refer to
section 3.1 of this appendix, except for sections 3.1.3 and 3.1.4,
which are requirements for indoor air volume and outdoor air volume.
For indoor air volume and outdoor air volume requirements, refer
instead to section 6.1.5 (except where section 6.1.5 refers to Table
8, refer instead to Table 3 of this appendix) and 6.1.6 of AHRI
1230-2010.
For the test method, refer to sections 3.3 to 3.5 and 3.7 to
3.13 of this appendix. For cooling mode and heating mode test
conditions, refer to section 6.2 of AHRI 1230-2010. For calculations
of seasonal performance descriptors, refer to section 4 of this
appendix.
(B) For systems other than VRF, only a subset of the sections
listed in this test procedure apply when testing and determining
represented values for a particular unit. Table 1 shows the sections
of the test procedure that apply to each system. This table is meant
to assist manufacturers in finding the appropriate sections of the
test procedure; the appendix sections rather than the table provide
the specific requirements for testing, and given the varied nature
of available units, manufacturers are responsible for determining
which sections apply to each unit tested based on the model
characteristics. To use this table, first refer to the sections
listed under ``all units''. Then refer to additional requirements
based on:
(1) System configuration(s),
(2) The compressor staging or modulation capability, and
(3) Any special features.
Testing requirements for space-constrained products do not
differ from similar equipment that is not space-constrained and thus
are not listed separately in this table. Air conditioners and heat
pumps are not listed separately in this table, but heating
procedures and calculations apply only to heat pumps.
[[Page 58215]]
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2.1 Test Room Requirements
a. Test using two side-by-side rooms: an indoor test room and an
outdoor test room. For multiple-split, single-zone-multi-coil or
multi-circuit air conditioners and heat pumps, however, use as many
indoor test rooms as needed to accommodate the total number of
indoor units. These rooms must comply with the requirements
specified in sections 8.1.2 and 8.1.3 of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3).
b. Inside these test rooms, use artificial loads during cyclic
tests and frost accumulation tests, if needed, to produce stabilized
room air temperatures. For one room, select an electric resistance
heater(s) having a heating capacity that is approximately equal to
the heating capacity of the test unit's condenser. For the second
room, select a heater(s) having a capacity that is close to the
sensible cooling capacity of the test unit's evaporator. Cycle the
heater located in the same room as the test unit evaporator coil ON
and OFF when the test unit cycles ON and OFF. Cycle the heater
located in the same room as the test unit condensing coil ON and OFF
when the test unit cycles OFF and ON.
2.2 Test Unit Installation Requirements
a. Install the unit according to section 8.2 of ANSI/ASHRAE 37-
2009 (incorporated by reference, see Sec. 430.3), subject to the
following additional requirements:
(1) When testing split systems, follow the requirements given in
section 6.1.3.5 of AHRI 210/240-2008 (incorporated by reference, see
Sec. 430.3). For the vapor refrigerant line(s), use the insulation
included with the unit; if no insulation is provided, use insulation
meeting the specifications for the insulation in the installation
instructions included with the unit by the manufacturer; if no
insulation is included with the unit and the installation
instructions do not contain provisions for insulating the line(s),
fully insulate the vapor refrigerant line(s) with vapor proof
insulation having an inside diameter that matches the refrigerant
tubing and a nominal thickness of at least 0.5 inches. For the
liquid refrigerant line(s), use the insulation included with the
unit; if no insulation is provided, use insulation meeting the
specifications for the insulation in the installation instructions
included with the unit by the manufacturer; if no insulation is
included with the unit and the installation instructions do not
contain provisions for insulating the line(s), leave the liquid
refrigerant line(s) exposed to the air for air conditioners and heat
pumps that heat and cool; or, for heating-only heat pumps, insulate
the liquid refrigerant line(s) with insulation having an inside
diameter that matches the refrigerant tubing and a nominal thickness
of at least 0.5 inches. Insulation must be the same for the cooling
and heating tests.
(2) When testing split systems, if the indoor unit does not ship
with a cooling mode expansion device, test the system using the
device as specified in the installation instructions provided with
the indoor unit. If none is specified, test the system using a fixed
orifice or piston type expansion device that is sized appropriately
for the system.
(3) When testing triple-split systems (see section 1.2 of this
appendix, Definitions), use the tubing length specified in section
6.1.3.5 of AHRI 210/240-2008 (incorporated by reference, see Sec.
430.3) to connect the outdoor coil, indoor compressor section, and
indoor coil while still meeting the requirement of exposing 10 feet
of the tubing to outside conditions;
(4) When testing split systems having multiple indoor coils,
connect each indoor blower coil unit to the outdoor unit using:
(a) 25 feet of tubing, or
(b) Tubing furnished by the manufacturer, whichever is longer.
(5) When testing split systems having multiple indoor coils,
expose at least 10 feet of the system interconnection tubing to the
outside conditions. If they are needed to make a secondary
measurement of capacity or for verification of refrigerant charge,
install refrigerant pressure measuring instruments as described in
section 8.2.5 of ANSI/ASHRAE 37-2009 (incorporated by reference, see
Sec. 430.3). Section 2.10 of this appendix specifies which
secondary methods require refrigerant pressure measurements and
section 2.2.5.5 of this appendix discusses use of pressure
measurements to verify charge. At a minimum, insulate the low-
pressure line(s) of a split system with insulation having an inside
diameter that matches the refrigerant tubing and a nominal thickness
of 0.5 inch.
b. For units designed for both horizontal and vertical
installation or for both up-flow and down-flow vertical
installations, use the orientation for testing specified by the
manufacturer in the certification report. Conduct testing with the
following installed:
(1) The most restrictive filter(s);
(2) Supplementary heating coils; and
(3) Other equipment specified as part of the unit, including all
hardware used by a heat comfort controller if so equipped (see
section 1 of this appendix, Definitions). For small-duct, high-
velocity systems, configure all balance dampers or restrictor
devices on or inside the unit to fully open or lowest restriction.
c. Testing a ducted unit without having an indoor air filter
installed is permissible as long as the minimum external static
pressure requirement is adjusted as stated in Table 3, note 3 (see
section 3.1.4 of this appendix). Except as noted in section 3.1.10
of this appendix, prevent the indoor air supplementary heating coils
from operating during all tests. For uncased coils, create an
enclosure using 1 inch fiberglass foil-faced ductboard having a
nominal density of 6 pounds per cubic foot. Or alternatively,
construct an enclosure using sheet metal or a similar material and
insulating material having a thermal resistance (``R'' value)
between 4 and 6 hr[middot]ft\2\[middot] [deg]F/Btu. Size the
enclosure and seal between the coil and/or drainage pan and the
interior of the enclosure as specified in installation instructions
shipped with the unit. Also seal between the plenum and inlet and
outlet ducts.
d. When testing a coil-only system, install a toroidal-type
transformer to power the system's low-voltage components, complying
with any additional requirements for the transformer mentioned in
the installation manuals included with the unit by the system
manufacturer. If the installation manuals do not provide
specifications for the transformer, use a transformer having the
following features:
(1) A nominal volt-amp rating such that the transformer is
loaded between 25 and 90 percent of this rating for the highest
level of power measured during the off mode test (section 3.13 of
this appendix);
(2) Designed to operate with a primary input of 230 V, single
phase, 60 Hz; and
(3) That provides an output voltage that is within the specified
range for each low-voltage component. Include the power consumption
of the components connected to the transformer as part of the total
system power consumption during the off mode tests; do not include
the power consumed by the transformer when no load is connected to
it.
e. Test an outdoor unit with no match (i.e., that is not
distributed in commerce with any indoor units) using a coil-only
indoor unit with a single cooling air volume rate whose coil has:
(1) Round tubes of outer diameter no less than 0.375 inches, and
(2) A normalized gross indoor fin surface (NGIFS) no greater
than 1.0 square inches per British thermal unit per hour (sq. in./
Btu/hr). NGIFS is calculated as follows:
NGIFS = 2 x Lf x Wf x Nf / Qc(95)
Where,
Lf = Indoor coil fin length in inches, also height of the
coil transverse to the tubes.
Wf = Indoor coil fin width in inches, also depth of the
coil.
Nf = Number of fins.
Qc = the measured space cooling capacity of the tested outdoor unit/
indoor unit combination as determined from the A2 or A Test
whichever applies, Btu/h.
f. If the outdoor unit or the outdoor portion of a single-
package unit has a drain pan heater to prevent freezing of defrost
water, energize the heater, subject to control to de-energize it
when not needed by the heater's thermostat or the unit's control
system, for all tests.
g. If pressure measurement devices are connected to refrigerant
lines at locations where the refrigerant state changes from liquid
to vapor for different parts of the test (e.g. heating mode vs.
cooling mode, on-cycle vs. off-cycle during cyclic test), the total
internal volume of the pressure measurement system (transducers,
gauges, connections, and lines) must be no more than 0.25 cubic
inches per 12,000 Btu/h certified cooling capacity. Calculate total
system internal volume using internal volume reported for pressure
transducers and gauges in product literature, if available. If such
information is not available, use the value of 0.1 cubic inches
internal volume for each pressure transducer, and 0.2 cubic inches
for each pressure gauge.
h. For single-split-system coil-only air conditioners, test
using an indoor coil that has a normalized gross indoor fin surface
(NGIFS) no greater than 2.5 square inches per British thermal unit
per hour (sq. in./Btu/hr). NGIFS is calculated as follows:
NGIFS = 2 x Lf x Wf x Nf / Qc(95)
Where,
[[Page 58219]]
Lf = Indoor coil fin length in inches, also height of the
coil transverse to the tubes.
Wf = Indoor coil fin width in inches, also depth of the
coil.
Nf = Number of fins.
Qc = the measured space cooling capacity of the tested outdoor unit/
indoor unit combination as determined from the A2 or A Test
whichever applies, Btu/h.
2.2.1 Defrost Control Settings
Set heat pump defrost controls at the normal settings which most
typify those encountered in generalized climatic region IV. (Refer
to Figure 1 and Table 19 of section 4.2 of this appendix for
information on region IV.) For heat pumps that use a time-adaptive
defrost control system (see section 1.2 of this appendix,
Definitions), the manufacturer must specify in the certification
report the frosting interval to be used during frost accumulation
tests and provide the procedure for manually initiating the defrost
at the specified time.
2.2.2 Special Requirements for Units Having a Multiple-Speed Outdoor
Fan
Configure the multiple-speed outdoor fan according to the
installation manual included with the unit by the manufacturer, and
thereafter, leave it unchanged for all tests. The controls of the
unit must regulate the operation of the outdoor fan during all lab
tests except dry coil cooling mode tests. For dry coil cooling mode
tests, the outdoor fan must operate at the same speed used during
the required wet coil test conducted at the same outdoor test
conditions.
2.2.3 Special Requirements for Multi-Split Air Conditioners and Heat
Pumps and Ducted Systems Using a Single Indoor Section Containing
Multiple Indoor Blowers that Would Normally Operate Using Two or More
Indoor Thermostats
Because these systems will have more than one indoor blower and
possibly multiple outdoor fans and compressor systems, references in
this test procedure to a singular indoor blower, outdoor fan, and/or
compressor means all indoor blowers, all outdoor fans, and all
compressor systems that are energized during the test.
a. Additional requirements for multi-split air conditioners and
heat pumps. For any test where the system is operated at part load
(i.e., one or more compressors ``off'', operating at the
intermediate or minimum compressor speed, or at low compressor
capacity), the manufacturer must designate in the certification
report the indoor coil(s) that are not providing heating or cooling
during the test. For variable-speed systems, the manufacturer must
designate in the certification report at least one indoor unit that
is not providing heating or cooling for all tests conducted at
minimum compressor speed. For all other part-load tests, the
manufacturer must choose to turn off zero, one, two, or more indoor
units. The chosen configuration must remain unchanged for all tests
conducted at the same compressor speed/capacity. For any indoor coil
that is not providing heating or cooling during a test, cease forced
airflow through this indoor coil and block its outlet duct.
b. Additional requirements for ducted split systems with a
single indoor unit containing multiple indoor blowers (or for
single-package units with an indoor section containing multiple
indoor blowers) where the indoor blowers are designed to cycle on
and off independently of one another and are not controlled such
that all indoor blowers are modulated to always operate at the same
air volume rate or speed. For any test where the system is operated
at its lowest capacity--i.e., the lowest total air volume rate
allowed when operating the single-speed compressor or when operating
at low compressor capacity--turn off indoor blowers accounting for
at least one-third of the full-load air volume rate unless prevented
by the controls of the unit. In such cases, turn off as many indoor
blowers as permitted by the unit's controls. Where more than one
option exists for meeting this ``off'' requirement, the manufacturer
must indicate in its certification report which indoor blower(s) are
turned off. The chosen configuration shall remain unchanged for all
tests conducted at the same lowest capacity configuration. For any
indoor coil turned off during a test, cease forced airflow through
any outlet duct connected to a switched-off indoor blower.
c. For test setups where the laboratory's physical limitations
require use of more than the required line length of 25 feet as
listed in section 2.2.a.(4) of this appendix, then the actual
refrigerant line length used by the laboratory may exceed the
required length and the refrigerant line length correction factors
in Table 4 of AHRI 1230-2010 are applied to the cooling capacity
measured for each cooling mode test.
2.2.4 Wet-Bulb Temperature Requirements for the Air Entering the Indoor
and Outdoor Coils
2.2.4.1 Cooling Mode Tests
For wet-coil cooling mode tests, regulate the water vapor
content of the air entering the indoor unit so that the wet-bulb
temperature is as listed in Tables 4 to 7. As noted in these same
tables, achieve a wet-bulb temperature during dry-coil cooling mode
tests that results in no condensate forming on the indoor coil.
Controlling the water vapor content of the air entering the outdoor
side of the unit is not required for cooling mode tests except when
testing:
(1) Units that reject condensate to the outdoor coil during wet
coil tests. Tables 4-7 list the applicable wet-bulb temperatures.
(2) Single-package units where all or part of the indoor section
is located in the outdoor test room. The average dew point
temperature of the air entering the outdoor coil during wet coil
tests must be within 3.0[emsp14][deg]F of the average
dew point temperature of the air entering the indoor coil over the
30-minute data collection interval described in section 3.3 of this
appendix. For dry coil tests on such units, it may be necessary to
limit the moisture content of the air entering the outdoor coil of
the unit to meet the requirements of section 3.4 of this appendix.
2.2.4.2 Heating Mode Tests
For heating mode tests, regulate the water vapor content of the
air entering the outdoor unit to the applicable wet-bulb temperature
listed in Tables 11 to 14. The wet-bulb temperature entering the
indoor side of the heat pump must not exceed 60[emsp14][deg]F.
Additionally, if the Outdoor Air Enthalpy test method (section
2.10.1 of this appendix) is used while testing a single-package heat
pump where all or part of the outdoor section is located in the
indoor test room, adjust the wet-bulb temperature for the air
entering the indoor side to yield an indoor-side dew point
temperature that is as close as reasonably possible to the dew point
temperature of the outdoor-side entering air.
2.2.5 Additional Refrigerant Charging Requirements
2.2.5.1 Instructions To Use for Charging
a. Where the manufacturer's installation instructions contain
two sets of refrigerant charging criteria, one for field
installations and one for lab testing, use the field installation
criteria.
b. For systems consisting of an outdoor unit manufacturer's
outdoor section and indoor section with differing charging
procedures, adjust the refrigerant charge per the outdoor
installation instructions.
c. For systems consisting of an outdoor unit manufacturer's
outdoor unit and an independent coil manufacturer's indoor unit with
differing charging procedures, adjust the refrigerant charge per the
indoor unit's installation instructions. If instructions are
provided only with the outdoor unit or are provided only with an
independent coil manufacturer's indoor unit, then use the provided
instructions.
2.2.5.2 Test(s) To Use for Charging
a. Use the tests or operating conditions specified in the
manufacturer's installation instructions for charging. The
manufacturer's installation instructions may specify use of tests
other than the A or A2 test for charging, but, unless the
unit is a heating-only heat pump, determine the air volume rate by
the A or A2 test as specified in section 3.1 of this
appendix.
b. If the manufacturer's installation instructions do not
specify a test or operating conditions for charging or there are no
manufacturer's instructions, use the following test(s):
(1) For air conditioners or cooling and heating heat pumps, use
the A or A2 test.
(2) For cooling and heating heat pumps that do not operate in
the H1 or H12 test (e.g. due to shut down by the unit
limiting devices) when tested using the charge determined at the A
or A2 test, and for heating-only heat pumps, use the H1
or H12 test.
2.2.5.3 Parameters To Set and Their Target Values
a. Consult the manufacturer's installation instructions
regarding which parameters (e.g., superheat) to set and their target
values. If the instructions provide ranges of values, select target
values equal to the midpoints of the provided ranges.
b. In the event of conflicting information between charging
instructions (i.e., multiple conditions given for charge adjustment
where all conditions specified cannot be met), follow the following
hierarchy.
(1) For fixed orifice systems:
(i) Superheat
[[Page 58220]]
(ii) High side pressure or corresponding saturation or dew-point
temperature
(iii) Low side pressure or corresponding saturation or dew-point
temperature
(iv) Low side temperature
(v) High side temperature
(vi) Charge weight
(2) For expansion valve systems:
(i) Subcooling
(ii) High side pressure or corresponding saturation or dew-point
temperature
(iii) Low side pressure or corresponding saturation or dew-point
temperature
(iv) Approach temperature (difference between temperature of liquid
leaving condenser and condenser average inlet air temperature)
(v) Charge weight
c. If there are no installation instructions and/or they do not
provide parameters and target values, set superheat to a target
value of 12 [deg]F for fixed orifice systems or set subcooling to a
target value of 10 [deg]F for expansion valve systems.
2.2.5.4 Charging Tolerances
a. If the manufacturer's installation instructions specify
tolerances on target values for the charging parameters, set the
values within these tolerances.
b. Otherwise, set parameter values within the following test
condition tolerances for the different charging parameters:
1. Superheat: 2.0 [deg]F
2. Subcooling: 2.0 [deg]F
3. High side pressure or corresponding saturation or dew point
temperature: 4.0 psi or 1.0 [deg]F
4. Low side pressure or corresponding saturation or dew point
temperature: 2.0 psi or 0.8 [deg]F
5. High side temperature: 2.0 [deg]F
6. Low side temperature: 2.0 [deg]F
7. Approach temperature: 1.0 [deg]F
8. Charge weight: 2.0 ounce
2.2.5.5 Special Charging Instructions
a. Cooling and Heating Heat Pumps
If, using the initial charge set in the A or A2 test,
the conditions are not within the range specified in manufacturer's
installation instructions for the H1 or H12 test, make as
small as possible an adjustment to obtain conditions for this test
in the specified range. After this adjustment, recheck conditions in
the A or A2 test to confirm that they are still within
the specified range for the A or A2 test.
b. Single-Package Systems
i. Unless otherwise directed by the manufacturer's installation
instructions, install one or more refrigerant line pressure gauges
during the setup of the unit, located depending on the parameters
used to verify or set charge, as described:
(1) Install a pressure gauge at the location of the service
valve on the liquid line if charging is on the basis of subcooling,
or high side pressure or corresponding saturation or dew point
temperature;
(2) Install a pressure gauge at the location of the service
valve on the suction line if charging is on the basis of superheat,
or low side pressure or corresponding saturation or dew point
temperature.
ii. Use methods for installing pressure gauge(s) at the required
location(s) as indicated in manufacturer's instructions if
specified.
2.2.5.6 Near-Azeotropic and Zeotropic Refrigerants
Perform charging of near-azeotropic and zeotropic refrigerants
only with refrigerant in the liquid state.
2.2.5.7 Adjustment of Charge Between Tests
After charging the system as described in this test procedure,
use the set refrigerant charge for all tests used to determine
performance. Do not adjust the refrigerant charge at any point
during testing. If measurements indicate that refrigerant charge has
leaked during the test, repair the refrigerant leak, repeat any
necessary set-up steps, and repeat all tests.
2.3 Indoor Air Volume Rates
If a unit's controls allow for overspeeding the indoor blower
(usually on a temporary basis), take the necessary steps to prevent
overspeeding during all tests.
2.3.1 Cooling Tests
a. Set indoor blower airflow-control settings (e.g., fan motor
pin settings, fan motor speed) according to the requirements that
are specified in section 3.1.4 of this appendix.
b. Express the Cooling full-load air volume rate, the Cooling
Minimum Air Volume Rate, and the Cooling Intermediate Air Volume
Rate in terms of standard air.
2.3.2 Heating Tests
a. Set indoor blower airflow-control settings (e.g., fan motor
pin settings, fan motor speed) according to the requirements that
are specified in section 3.1.4 of this appendix.
b. Express the heating full-load air volume rate, the heating
minimum air volume rate, the heating intermediate air volume rate,
and the heating nominal air volume rate in terms of standard air.
2.4 Indoor Coil Inlet and Outlet Duct Connections. Insulate and/
or construct the outlet plenum as described in section 2.4.1 of this
appendix and, if installed, the inlet plenum described in section
2.4.2 of this appendix with thermal insulation having a nominal
overall resistance (R-value) of at least 19 hr[middot]ft\2\[middot]
[deg]F/Btu.
2.4.1 Outlet Plenum for the Indoor Unit
a. Attach a plenum to the outlet of the indoor coil. (Note: For
some packaged systems, the indoor coil may be located in the outdoor
test room.)
b. For systems having multiple indoor coils, or multiple indoor
blowers within a single indoor section, attach a plenum to each
indoor coil or indoor blower outlet. In order to reduce the number
of required airflow measurement apparati (section 2.6 of this
appendix), each such apparatus may serve multiple outlet plenums
connected to a single common duct leading to the apparatus. More
than one indoor test room may be used, which may use one or more
common ducts leading to one or more airflow measurement apparati
within each test room that contains multiple indoor coils. At the
plane where each plenum enters a common duct, install an adjustable
airflow damper and use it to equalize the static pressure in each
plenum. The outlet air temperature grid(s) (section 2.5.4 of this
appendix) and airflow measuring apparatus shall be located
downstream of the inlet(s) to the common duct(s). For multiple-
circuit (or multi-circuit) systems for which each indoor coil outlet
is measured separately and its outlet plenum is not connected to a
common duct connecting multiple outlet plenums, install the outlet
air temperature grid and airflow measuring apparatus at each outlet
plenum.
c. For small-duct, high-velocity systems, install an outlet
plenum that has a diameter that is equal to or less than the value
listed in Table 2. The limit depends only on the Cooling full-load
air volume rate (see section 3.1.4.1.1 of this appendix) and is
effective regardless of the flange dimensions on the outlet of the
unit (or an air supply plenum adapter accessory, if installed in
accordance with the manufacturer's installation instructions).
d. Add a static pressure tap to each face of the (each) outlet
plenum, if rectangular, or at four evenly distributed locations
along the circumference of an oval or round plenum. Create a
manifold that connects the four static pressure taps. Figure 9 of
ANSI/ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3)
shows allowed options for the manifold configuration. The cross-
sectional dimensions of plenum must be equal to the dimensions of
the indoor unit outlet. See Figures 7a, 7b, and 7c of ANSI/ASHRAE
37-2009 for the minimum length of the (each) outlet plenum and the
locations for adding the static pressure taps for ducted blower coil
indoor units and single-package systems. See Figure 8 of ANSI/ASHRAE
37-2009 for coil-only indoor units.
Table 2--Size of Outlet Plenum for Small-Duct High-Velocity Indoor Units
------------------------------------------------------------------------
Maximum
diameter * of
Cooling full-load air volume rate (scfm) outlet plenum
(inches)
------------------------------------------------------------------------
<=500................................................... 6
501 to 700.............................................. 7
701 to 900.............................................. 8
901 to 1100............................................. 9
1101 to 1400............................................ 10
1401 to 1750............................................ 11
------------------------------------------------------------------------
* If the outlet plenum is rectangular, calculate its equivalent diameter
using (4A/P,) where A is the cross-sectional area and P is the
perimeter of the rectangular plenum, and compare it to the listed
maximum diameter.
2.4.2 Inlet Plenum for the Indoor Unit
Install an inlet plenum when testing a coil-only indoor unit, a
ducted blower coil indoor unit, or a single-package system. See
Figures 7b and 7c of ANSI/ASHRAE 37-2009 for cross-sectional
dimensions, the minimum length of the inlet plenum, and the
locations of the static-pressure taps for ducted blower coil indoor
units and single-package systems. See Figure 8 of ANSI/ASHRAE 37-
2009 for coil-only indoor units. The inlet plenum duct
[[Page 58221]]
size shall equal the size of the inlet opening of the air-handling
(blower coil) unit or furnace. For a ducted blower coil indoor unit
the set up may omit the inlet plenum if an inlet airflow prevention
device is installed with a straight internally unobstructed duct on
its outlet end with a minimum length equal to 1.5 times the square
root of the cross-sectional area of the indoor unit inlet. See
section 2.1.5.2 of this appendix for requirements for the locations
of static pressure taps built into the inlet airflow prevention
device. For all of these arrangements, make a manifold that connects
the four static-pressure taps using one of the three configurations
specified in section 2.4.1.d. of this appendix. Never use an inlet
plenum when testing a non-ducted system.
2.5 Indoor Coil Air Property Measurements and Airflow Prevention
Devices
Follow instructions for indoor coil air property measurements as
described in section 2.14 of this appendix, unless otherwise
instructed in this section.
a. Measure the dry-bulb temperature and water vapor content of
the air entering and leaving the indoor coil. If needed, use an air
sampling device to divert air to a sensor(s) that measures the water
vapor content of the air. See section 5.3 of ANSI/ASHRAE 41.1-2013
(incorporated by reference, see Sec. 430.3) for guidance on
constructing an air sampling device. No part of the air sampling
device or the tubing transferring the sampled air to the sensor must
be within two inches of the test chamber floor, and the transfer
tubing must be insulated. The sampling device may also be used for
measurement of dry bulb temperature by transferring the sampled air
to a remotely located sensor(s). The air sampling device and the
remotely located temperature sensor(s) may be used to determine the
entering air dry bulb temperature during any test. The air sampling
device and the remotely located sensor(s) may be used to determine
the leaving air dry bulb temperature for all tests except:
(1) Cyclic tests; and
(2) Frost accumulation tests.
b. Install grids of temperature sensors to measure dry bulb
temperatures of both the entering and leaving airstreams of the
indoor unit. These grids of dry bulb temperature sensors may be used
to measure average dry bulb temperature entering and leaving the
indoor unit in all cases (as an alternative to the dry bulb sensor
measuring the sampled air). The leaving airstream grid is required
for measurement of average dry bulb temperature leaving the indoor
unit for the two special cases noted in preamble. The grids are also
required to measure the air temperature distribution of the entering
and leaving airstreams as described in sections 3.1.8 of this
appendix. Two such grids may be applied as a thermopile, to directly
obtain the average temperature difference rather than directly
measuring both entering and leaving average temperatures.
c. Use of airflow prevention devices. Use an inlet and outlet
air damper box, or use an inlet upturned duct and an outlet air
damper box when conducting one or both of the cyclic tests listed in
sections 3.2 and 3.6 of this appendix on ducted systems. If not
conducting any cyclic tests, an outlet air damper box is required
when testing ducted and non-ducted heat pumps that cycle off the
indoor blower during defrost cycles and there is no other means for
preventing natural or forced convection through the indoor unit when
the indoor blower is off. Never use an inlet damper box or an inlet
upturned duct when testing non-ducted indoor units. An inlet
upturned duct is a length of ductwork installed upstream from the
inlet such that the indoor duct inlet opening, facing upwards, is
sufficiently high to prevent natural convection transfer out of the
duct. If an inlet upturned duct is used, install a dry bulb
temperature sensor near the inlet opening of the indoor duct at a
centerline location not higher than the lowest elevation of the duct
edges at the inlet, and ensure that any pair of 5-minute averages of
the dry bulb temperature at this location, measured at least every
minute during the compressor OFF period of the cyclic test, do not
differ by more than 1.0 [deg]F.
2.5.1 Test Set-Up on the Inlet Side of the Indoor Coil: For Cases Where
the Inlet Airflow Prevention Device is Installed
a. Install an airflow prevention device as specified in section
2.5.1.1 or 2.5.1.2 of this appendix, whichever applies.
b. For an inlet damper box, locate the grid of entering air dry-
bulb temperature sensors, if used, and the air sampling device, or
the sensor used to measure the water vapor content of the inlet air,
at a location immediately upstream of the damper box inlet. For an
inlet upturned duct, locate the grid of entering air dry-bulb
temperature sensors, if used, and the air sampling device, or the
sensor used to measure the water vapor content of the inlet air, at
a location at least one foot downstream from the beginning of the
insulated portion of the duct but before the static pressure
measurement.
2.5.1.1 If the section 2.4.2 inlet plenum is installed,
construct the airflow prevention device having a cross-sectional
flow area equal to or greater than the flow area of the inlet
plenum. Install the airflow prevention device upstream of the inlet
plenum and construct ductwork connecting it to the inlet plenum. If
needed, use an adaptor plate or a transition duct section to connect
the airflow prevention device with the inlet plenum. Insulate the
ductwork and inlet plenum with thermal insulation that has a nominal
overall resistance (R-value) of at least 19 hr [middot]ft\2\
[middot] [deg]F/Btu.
2.5.1.2 If the section 2.4.2 inlet plenum is not installed,
construct the airflow prevention device having a cross-sectional
flow area equal to or greater than the flow area of the air inlet of
the indoor unit. Install the airflow prevention device immediately
upstream of the inlet of the indoor unit. If needed, use an adaptor
plate or a short transition duct section to connect the airflow
prevention device with the unit's air inlet. Add static pressure
taps at the center of each face of a rectangular airflow prevention
device, or at four evenly distributed locations along the
circumference of an oval or round airflow prevention device. Locate
the pressure taps at a distance from the indoor unit inlet equal to
0.5 times the square root of the cross sectional area of the indoor
unit inlet. This location must be between the damper and the inlet
of the indoor unit, if a damper is used. Make a manifold that
connects the four static pressure taps using one of the
configurations shown in Figure 9 of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3). Insulate the ductwork
with thermal insulation that has a nominal overall resistance (R-
value) of at least 19 hr[middot]ft\2\ [middot] [deg]F/Btu.
2.5.2 Test Set-Up on the Inlet Side of the Indoor Unit: For Cases Where
No Airflow Prevention Device is Installed
If using the section 2.4.2 inlet plenum and a grid of dry bulb
temperature sensors, mount the grid at a location upstream of the
static pressure taps described in section 2.4.2 of this appendix,
preferably at the entrance plane of the inlet plenum. If the section
2.4.2 inlet plenum is not used (i.e. for non-ducted units) locate a
grid approximately 6 inches upstream of the indoor unit inlet. In
the case of a system having multiple non-ducted indoor units, do
this for each indoor unit. Position an air sampling device, or the
sensor used to measure the water vapor content of the inlet air,
immediately upstream of the (each) entering air dry-bulb temperature
sensor grid. If a grid of sensors is not used, position the entering
air sampling device (or the sensor used to measure the water vapor
content of the inlet air) as if the grid were present.
2.5.3 Indoor Coil Static Pressure Difference Measurement
Fabricate pressure taps meeting all requirements described in
section 6.5.2 of ANSI/ASHRAE 37-2009 (incorporated by reference, see
Sec. 430.3) and illustrated in Figure 2A of AMCA 210-2007
(incorporated by reference, see Sec. 430.3), however, if adhering
strictly to the description in section 6.5.2 of ANSI/ASHRAE 37-2009,
the minimum pressure tap length of 2.5 times the inner diameter of
Figure 2A of AMCA 210-2007 is waived. Use a differential pressure
measuring instrument that is accurate to within 0.01
inches of water and has a resolution of at least 0.01 inches of
water to measure the static pressure difference between the indoor
coil air inlet and outlet. Connect one side of the differential
pressure instrument to the manifolded pressure taps installed in the
outlet plenum. Connect the other side of the instrument to the
manifolded pressure taps located in either the inlet plenum or
incorporated within the airflow prevention device. For non-ducted
systems that are tested with multiple outlet plenums, measure the
static pressure within each outlet plenum relative to the
surrounding atmosphere.
2.5.4 Test Set-Up on the Outlet Side of the Indoor Coil
a. Install an interconnecting duct between the outlet plenum
described in section 2.4.1 of this appendix and the airflow
measuring apparatus described below in section 2.6 of this appendix.
The cross-sectional flow area of the interconnecting duct must be
equal to or greater than the flow area of the outlet plenum or the
common duct used when testing non-ducted units having multiple
indoor coils. If needed, use adaptor plates or
[[Page 58222]]
transition duct sections to allow the connections. To minimize
leakage, tape joints within the interconnecting duct (and the outlet
plenum). Construct or insulate the entire flow section with thermal
insulation having a nominal overall resistance (R-value) of at least
19 hr [middot] ft\2\ [middot] [deg]F/Btu.
b. Install a grid(s) of dry-bulb temperature sensors inside the
interconnecting duct. Also, install an air sampling device, or the
sensor(s) used to measure the water vapor content of the outlet air,
inside the interconnecting duct. Locate the dry-bulb temperature
grid(s) upstream of the air sampling device (or the in-duct
sensor(s) used to measure the water vapor content of the outlet
air). Turn off the sampler fan motor during the cyclic tests. Air
leaving an indoor unit that is sampled by an air sampling device for
remote water-vapor-content measurement must be returned to the
interconnecting duct at a location:
(1) Downstream of the air sampling device;
(2) On the same side of the outlet air damper as the air
sampling device; and
(3) Upstream of the section 2.6 airflow measuring apparatus.
2.5.4.1 Outlet Air Damper Box Placement and Requirements
If using an outlet air damper box (see section 2.5 of this
appendix), the leakage rate from the combination of the outlet
plenum, the closed damper, and the duct section that connects these
two components must not exceed 20 cubic feet per minute when a
negative pressure of 1 inch of water column is maintained at the
plenum's inlet.
2.5.4.2 Procedures To Minimize Temperature Maldistribution
Use these procedures if necessary to correct temperature
maldistributions. Install a mixing device(s) upstream of the outlet
air, dry-bulb temperature grid (but downstream of the outlet plenum
static pressure taps). Use a perforated screen located between the
mixing device and the dry-bulb temperature grid, with a maximum open
area of 40 percent. One or both items should help to meet the
maximum outlet air temperature distribution specified in section
3.1.8 of this appendix. Mixing devices are described in sections
5.3.2 and 5.3.3 of ANSI/ASHRAE 41.1-2013 and section 5.2.2 of ASHRAE
41.2-1987 (RA 1992) (incorporated by reference, see Sec. 430.3).
2.5.4.3 Minimizing Air Leakage
For small-duct, high-velocity systems, install an air damper
near the end of the interconnecting duct, just prior to the
transition to the airflow measuring apparatus of section 2.6 of this
appendix. To minimize air leakage, adjust this damper such that the
pressure in the receiving chamber of the airflow measuring apparatus
is no more than 0.5 inch of water higher than the surrounding test
room ambient. If applicable, in lieu of installing a separate
damper, use the outlet air damper box of sections 2.5 and 2.5.4.1 of
this appendix if it allows variable positioning. Also apply these
steps to any conventional indoor blower unit that creates a static
pressure within the receiving chamber of the airflow measuring
apparatus that exceeds the test room ambient pressure by more than
0.5 inches of water column.
2.5.5 Dry Bulb Temperature Measurement
a. Measure dry bulb temperatures as specified in sections 4,
5.3, 6, and 7 of ANSI/ASHRAE 41.1-2013 (incorporated by reference,
see Sec. 430.3).
b. Distribute the sensors of a dry-bulb temperature grid over
the entire flow area. The required minimum is 9 sensors per grid.
2.5.6 Water Vapor Content Measurement
Determine water vapor content by measuring dry-bulb temperature
combined with the air wet-bulb temperature, dew point temperature,
or relative humidity. If used, construct and apply wet-bulb
temperature sensors as specified in sections 4, 5, 6, 7.2, 7.3, and
7.4 of ASHRAE 41.6-2014 (incorporated by reference, see Sec.
430.3). The temperature sensor (wick removed) must be accurate to
within 0.2[emsp14][deg]F. If used, apply dew point
hygrometers as specified in sections 4, 5, 6, 7.1, and 7.4 of ASHRAE
41.6-2014. The dew point hygrometers must be accurate to within
0.4[emsp14][deg]F when operated at conditions that
result in the evaluation of dew points above 35[emsp14][deg]F. If
used, a relative humidity (RH) meter must be accurate to within
0.7% RH. Other means to determine the psychrometric
state of air may be used as long as the measurement accuracy is
equivalent to or better than the accuracy achieved from using a wet-
bulb temperature sensor that meets the above specifications.
2.5.7 Air Damper Box Performance Requirements
If used (see section 2.5 of this appendix), the air damper
box(es) must be capable of being completely opened or completely
closed within 10 seconds for each action.
2.6 Airflow Measuring Apparatus
a. Fabricate and operate an airflow measuring apparatus as
specified in section 6.2 and 6.3 of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3). Place the static
pressure taps and position the diffusion baffle (settling means)
relative to the chamber inlet as indicated in Figure 12 of AMCA 210-
07 and/or Figure 14 of ASHRAE 41.2-1987 (RA 1992) (incorporated by
reference, see Sec. 430.3). When measuring the static pressure
difference across nozzles and/or velocity pressure at nozzle throats
using electronic pressure transducers and a data acquisition system,
if high frequency fluctuations cause measurement variations to
exceed the test tolerance limits specified in section 9.2 of this
appendix and Table 2 of ANSI/ASHRAE 37-2009, dampen the measurement
system such that the time constant associated with response to a
step change in measurement (time for the response to change 63% of
the way from the initial output to the final output) is no longer
than five seconds.
b. Connect the airflow measuring apparatus to the
interconnecting duct section described in section 2.5.4 of this
appendix. See sections 6.1.1, 6.1.2, and 6.1.4, and Figures 1, 2,
and 4 of ANSI/ASHRAE 37-2009; and Figures D1, D2, and D4 of AHRI
210/240-2008 (incorporated by reference, see Sec. 430.3) with
Addendum 1 and 2 for illustrative examples of how the test apparatus
may be applied within a complete laboratory set-up. Instead of
following one of these examples, an alternative set-up may be used
to handle the air leaving the airflow measuring apparatus and to
supply properly conditioned air to the test unit's inlet. The
alternative set-up, however, must not interfere with the prescribed
means for measuring airflow rate, inlet and outlet air temperatures,
inlet and outlet water vapor contents, and external static
pressures, nor create abnormal conditions surrounding the test unit.
(Note: Do not use an enclosure as described in section 6.1.3 of
ANSI/ASHRAE 37-2009 when testing triple-split units.)
2.7 Electrical Voltage Supply
Perform all tests at the voltage specified in section 6.1.3.2 of
AHRI 210/240-2008 (incorporated by reference, see Sec. 430.3) for
``Standard Rating Tests.'' If either the indoor or the outdoor unit
has a 208V or 200V nameplate voltage and the other unit has a 230V
nameplate rating, select the voltage supply on the outdoor unit for
testing. Otherwise, supply each unit with its own nameplate voltage.
Measure the supply voltage at the terminals on the test unit using a
volt meter that provides a reading that is accurate to within 1.0 percent of the measured quantity.
2.8 Electrical Power and Energy Measurements
a. Use an integrating power (watt-hour) measuring system to
determine the electrical energy or average electrical power supplied
to all components of the air conditioner or heat pump (including
auxiliary components such as controls, transformers, crankcase
heater, integral condensate pump on non-ducted indoor units, etc.).
The watt-hour measuring system must give readings that are accurate
to within 0.5 percent. For cyclic tests, this accuracy
is required during both the ON and OFF cycles. Use either two
different scales on the same watt-hour meter or two separate watt-
hour meters. Activate the scale or meter having the lower power
rating within 15 seconds after beginning an OFF cycle. Activate the
scale or meter having the higher power rating within 15 seconds
prior to beginning an ON cycle. For ducted blower coil systems, the
ON cycle lasts from compressor ON to indoor blower OFF. For ducted
coil-only systems, the ON cycle lasts from compressor ON to
compressor OFF. For non-ducted units, the ON cycle lasts from indoor
blower ON to indoor blower OFF. When testing air conditioners and
heat pumps having a variable-speed compressor, avoid using an
induction watt/watt-hour meter.
b. When performing section 3.5 and/or 3.8 cyclic tests on non-
ducted units, provide instrumentation to determine the average
electrical power consumption of the indoor blower motor to within
1.0 percent. If required according to sections 3.3, 3.4,
3.7, 3.9.1 of this appendix, and/or 3.10 of this appendix, this same
instrumentation requirement (to determine the average electrical
power consumption of the indoor blower motor to within 1.0 percent) applies when testing air conditioners and heat
pumps having a variable-speed constant-air-volume-rate indoor blower
or a variable-speed, variable-air-volume-rate indoor blower.
[[Page 58223]]
2.9 Time Measurements
Make elapsed time measurements using an instrument that yields
readings accurate to within 0.2 percent.
2.10 Test Apparatus for the Secondary Space Conditioning Capacity
Measurement
For all tests, use the indoor air enthalpy method to measure the
unit's capacity. This method uses the test set-up specified in
sections 2.4 to 2.6 of this appendix. In addition, for all steady-
state tests, conduct a second, independent measurement of capacity
as described in section 3.1.1 of this appendix. For split systems,
use one of the following secondary measurement methods: outdoor air
enthalpy method, compressor calibration method, or refrigerant
enthalpy method. For single-package units, use either the outdoor
air enthalpy method or the compressor calibration method as the
secondary measurement.
2.10.1 Outdoor Air Enthalpy Method
a. To make a secondary measurement of indoor space conditioning
capacity using the outdoor air enthalpy method, do the following:
(1) Measure the electrical power consumption of the test unit;
(2) Measure the air-side capacity at the outdoor coil; and
(3) Apply a heat balance on the refrigerant cycle.
b. The test apparatus required for the outdoor air enthalpy
method is a subset of the apparatus used for the indoor air enthalpy
method. Required apparatus includes the following:
(1) On the outlet side, an outlet plenum containing static
pressure taps (sections 2.4, 2.4.1, and 2.5.3 of this appendix),
(2) An airflow measuring apparatus (section 2.6 of this
appendix),
(3) A duct section that connects these two components and itself
contains the instrumentation for measuring the dry-bulb temperature
and water vapor content of the air leaving the outdoor coil
(sections 2.5.4, 2.5.5, and 2.5.6 of this appendix), and
(4) On the inlet side, a sampling device and temperature grid
(section 2.11.b of this appendix).
c. During the non-ducted tests described in sections 3.11.1 and
3.11.1.1 of this appendix, measure the evaporator and condenser
temperatures or pressures. On both the outdoor coil and the indoor
coil, solder a thermocouple onto a return bend located at or near
the midpoint of each coil or at points not affected by vapor
superheat or liquid subcooling. Alternatively, if the test unit is
not sensitive to the refrigerant charge, install pressure gages to
the access valves or to ports created from tapping into the suction
and discharge lines according to sections 7.4.2 and 8.2.5 of ASHRAE
37-2009. Use this alternative approach when testing a unit charged
with a zeotropic refrigerant having a temperature glide in excess of
1 [deg]F at the specified test conditions.
2.10.2 Compressor Calibration Method
Measure refrigerant pressures and temperatures to determine the
evaporator superheat and the enthalpy of the refrigerant that enters
and exits the indoor coil. Determine refrigerant flow rate or, when
the superheat of the refrigerant leaving the evaporator is less than
5[emsp14][deg]F, total capacity from separate calibration tests
conducted under identical operating conditions. When using this
method, install instrumentation and measure refrigerant properties
according to section 7.4.2 and 8.2.5 of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3). If removing the
refrigerant before applying refrigerant lines and subsequently
recharging, use the steps in 7.4.2 of ANSI/ASHRAE 37-2009 in
addition to the methods of section 2.2.5 of this appendix to confirm
the refrigerant charge. Use refrigerant temperature and pressure
measuring instruments that meet the specifications given in sections
5.1.1 and 5.2 of ANSI/ASHRAE 37-2009.
2.10.3 Refrigerant Enthalpy Method
For this method, calculate space conditioning capacity by
determining the refrigerant enthalpy change for the indoor coil and
directly measuring the refrigerant flow rate. Use section 7.5.2 of
ANSI/ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3) for
the requirements for this method, including the additional
instrumentation requirements, and information on placing the flow
meter and a sight glass. Use refrigerant temperature, pressure, and
flow measuring instruments that meet the specifications given in
sections 5.1.1, 5.2, and 5.5.1 of ANSI/ASHRAE 37-2009. Refrigerant
flow measurement device(s), if used, must be either elevated at
least two feet from the test chamber floor or placed upon insulating
material having a total thermal resistance of at least R-12 and
extending at least one foot laterally beyond each side of the
device(s)' exposed surfaces.
2.11 Measurement of Test Room Ambient Conditions
Follow instructions for setting up air sampling device and
aspirating psychrometer as described in section 2.14 of this
appendix, unless otherwise instructed in this section.
a. If using a test set-up where air is ducted directly from the
conditioning apparatus to the indoor coil inlet (see Figure 2, Loop
Air-Enthalpy Test Method Arrangement, of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3)), add instrumentation
to permit measurement of the indoor test room dry-bulb temperature.
b. On the outdoor side, use one of the following two approaches,
except that approach (1) is required for all evaporatively-cooled
units and units that transfer condensate to the outdoor unit for
evaporation using condenser heat.
(1) Use sampling tree air collection on all air-inlet surfaces
of the outdoor unit.
(2) Use sampling tree air collection on one or more faces of the
outdoor unit and demonstrate air temperature uniformity as follows.
Install a grid of evenly-distributed thermocouples on each air-
permitting face on the inlet of the outdoor unit. Install the
thermocouples on the air sampling device, locate them individually
or attach them to a wire structure. If not installed on the air
sampling device, install the thermocouple grid 6 to 24 inches from
the unit. Evenly space the thermocouples across the coil inlet
surface and install them to avoid sampling of discharge air or
blockage of air recirculation. The grid of thermocouples must
provide at least 16 measuring points per face or one measurement per
square foot of inlet face area, whichever is less. Construct this
grid and use as per section 5.3 of ANSI/ASHRAE 41.1-2013
(incorporated by reference, see Sec. 430.3). The maximum difference
between the average temperatures measured during the test period of
any two pairs of these individual thermocouples located at any of
the faces of the inlet of the outdoor unit, must not exceed
2.0[emsp14][deg]F, otherwise use approach (1).
Locate the air sampling devices at the geometric center of each
side; the branches may be oriented either parallel or perpendicular
to the longer edges of the air inlet area. Size the air sampling
devices in the outdoor air inlet location such that they cover at
least 75% of the face area of the side of the coil that they are
measuring.
Review air distribution at the test facility point of supply to
the unit and remediate as necessary prior to the beginning of
testing. Mixing fans can be used to ensure adequate air distribution
in the test room. If used, orient mixing fans such that they are
pointed away from the air intake so that the mixing fan exhaust does
not affect the outdoor coil air volume rate. Particular attention
should be given to prevent the mixing fans from affecting (enhancing
or limiting) recirculation of condenser fan exhaust air back through
the unit. Any fan used to enhance test room air mixing shall not
cause air velocities in the vicinity of the test unit to exceed 500
feet per minute
The air sampling device may be larger than the face area of the
side being measured. Take care, however, to prevent discharge air
from being sampled. If an air sampling device dimension extends
beyond the inlet area of the unit, block holes in the air sampling
device to prevent sampling of discharge air. Holes can be blocked to
reduce the region of coverage of the intake holes both in the
direction of the trunk axis or perpendicular to the trunk axis. For
intake hole region reduction in the direction of the trunk axis,
block holes of one or more adjacent pairs of branches (the branches
of a pair connect opposite each other at the same trunk location) at
either the outlet end or the closed end of the trunk. For intake
hole region reduction perpendicular to the trunk axis, block off the
same number of holes on each branch on both sides of the trunk.
Connect a maximum of four (4) air sampling devices to each
aspirating psychrometer. In order to proportionately divide the flow
stream for multiple air sampling devices for a given aspirating
psychrometer, the tubing or conduit conveying sampled air to the
psychrometer must be of equivalent lengths for each air sampling
device. Preferentially, the air sampling device should be hard
connected to the aspirating psychrometer, but if space constraints
do not allow this, the assembly shall have a means of allowing a
flexible tube to connect the air sampling device to the aspirating
psychrometer. Insulate and route the tubing or conduit to prevent
heat transfer to the air stream. Insulate any surface of the
[[Page 58224]]
air conveying tubing in contact with surrounding air at a different
temperature than the sampled air with thermal insulation with a
nominal thermal resistance (R-value) of at least 19 hr [middot]
ft\2\ [middot] [deg]F/Btu. Alternatively the conduit may have lower
thermal resistance if additional sensor(s) are used to measure dry
bulb temperature at the outlet of each air sampling device. No part
of the air sampling device or the tubing conducting the sampled air
to the sensors may be within two inches of the test chamber floor.
Take pairs of measurements (e.g. dry bulb temperature and wet
bulb temperature) used to determine water vapor content of sampled
air in the same location.
2.12 Measurement of Indoor Blower Speed
When required, measure fan speed using a revolution counter,
tachometer, or stroboscope that gives readings accurate to within
1.0 percent.
2.13 Measurement of Barometric Pressure
Determine the average barometric pressure during each test. Use
an instrument that meets the requirements specified in section 5.2
of ANSI/ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3).
2.14 Air Sampling Device and Aspirating Psychrometer Requirements
Make air temperature measurements in accordance with ANSI/ASHRAE
41.1-2013 (incorporated by reference, see Sec. 430.3), unless
otherwise instructed in this section.
2.14.1 Air Sampling Device Requirements
The air sampling device is intended to draw in a sample of the
air at the critical locations of a unit under test. Construct the
device from stainless steel, plastic or other suitable, durable
materials. It shall have a main flow trunk tube with a series of
branch tubes connected to the trunk tube. Holes must be on the side
of the sampler facing the upstream direction of the air source. Use
other sizes and rectangular shapes, and scale them accordingly with
the following guidelines:
1. Minimum hole density of 6 holes per square foot of area to be
sampled
2. Sampler branch tube pitch (spacing) of 6 3 in
3. Manifold trunk to branch diameter ratio having a minimum of 3:1
ratio
4. Distribute hole pitch (spacing) equally over the branch (\1/2\
pitch from the closed end to the nearest hole)
5. Maximum individual hole to branch diameter ratio of 1:2 (1:3
preferred)
The minimum average velocity through the air sampling device
holes must be 2.5 ft/s as determined by evaluating the sum of the
open area of the holes as compared to the flow area in the
aspirating psychrometer.
2.14.2 Aspirating Psychrometer
The psychrometer consists of a flow section and a fan to draw
air through the flow section and measures an average value of the
sampled air stream. At a minimum, the flow section shall have a
means for measuring the dry bulb temperature (typically, a
resistance temperature device (RTD) and a means for measuring the
humidity (RTD with wetted sock, chilled mirror hygrometer, or
relative humidity sensor). The aspirating psychrometer shall include
a fan that either can be adjusted manually or automatically to
maintain required velocity across the sensors.
Construct the psychrometer using suitable material which may be
plastic (such as polycarbonate), aluminum or other metallic
materials. Construct all psychrometers for a given system being
tested, using the same material. Design the psychrometers such that
radiant heat from the motor (for driving the fan that draws sampled
air through the psychrometer) does not affect sensor measurements.
For aspirating psychrometers, velocity across the wet bulb sensor
must be 1000 200 ft/min. For all other psychrometers,
velocity must be as specified by the sensor manufacturer.
3. Testing Procedures
3.1 General Requirements
If, during the testing process, an equipment set-up adjustment
is made that would have altered the performance of the unit during
any already completed test, then repeat all tests affected by the
adjustment. For cyclic tests, instead of maintaining an air volume
rate, for each airflow nozzle, maintain the static pressure
difference or velocity pressure during an ON period at the same
pressure difference or velocity pressure as measured during the
steady-state test conducted at the same test conditions.
Use the testing procedures in this section to collect the data
used for calculating:
(1) Performance metrics for central air conditioners and heat
pumps during the cooling season;
(2) Performance metrics for heat pumps during the heating
season; and
(3) Power consumption metric(s) for central air conditioners and
heat pumps during the off mode season(s).
3.1.1 Primary and Secondary Test Methods
For all tests, use the indoor air enthalpy method test apparatus
to determine the unit's space conditioning capacity. The procedure
and data collected, however, differ slightly depending upon whether
the test is a steady-state test, a cyclic test, or a frost
accumulation test. The following sections described these
differences. For all steady-state tests (i.e., the A, A2,
A1, B, B2, B1, C, C1,
EV, F1, G1, H01, H1,
H12, H11, HIN, H3,
H32, and H31 Tests), in addition, use one of
the acceptable secondary methods specified in section 2.10 of this
appendix to determine indoor space conditioning capacity. Calculate
this secondary check of capacity according to section 3.11 of this
appendix. The two capacity measurements must agree to within 6
percent to constitute a valid test. For this capacity comparison,
use the Indoor Air Enthalpy Method capacity that is calculated in
section 7.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see
Sec. 430.3) (and, if testing a coil-only system, compare capacities
before making the after-test fan heat adjustments described in
section 3.3, 3.4, 3.7, and 3.10 of this appendix). However, include
the appropriate section 3.3 to 3.5 and 3.7 to 3.10 fan heat
adjustments within the indoor air enthalpy method capacities used
for the section 4 seasonal calculations of this appendix.
3.1.2 Manufacturer-Provided Equipment Overrides
Where needed, the manufacturer must provide a means for
overriding the controls of the test unit so that the compressor(s)
operates at the specified speed or capacity and the indoor blower
operates at the specified speed or delivers the specified air volume
rate.
3.1.3 Airflow Through the Outdoor Coil
For all tests, meet the requirements given in section 6.1.3.4 of
AHRI 210/240-2008 (incorporated by reference, see Sec. 430.3) when
obtaining the airflow through the outdoor coil.
3.1.3.1 Double-Ducted
For products intended to be installed with the outdoor airflow
ducted, install the unit with outdoor coil ductwork installed per
manufacturer installation instructions. The unit must operate
between 0.10 and 0.15 in H2O external static pressure.
Make external static pressure measurements in accordance with ANSI/
ASHRAE 37-2009 section 6.4 and 6.5.
3.1.4 Airflow Through the Indoor Coil
Determine airflow setting(s) before testing begins. Unless
otherwise specified within this or its subsections, make no changes
to the airflow setting(s) after initiation of testing.
3.1.4.1 Cooling Full-Load Air Volume Rate
3.1.4.1.1. Cooling Full-Load Air Volume Rate for Ducted Units
Identify the certified Cooling full-load air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified Cooling full-load air volume rate, use a value equal
to the certified cooling capacity of the unit times 400 scfm per
12,000 Btu/h. If there are no instructions for setting fan speed or
controls, use the as-shipped settings. Use the following procedure
to confirm and, if necessary, adjust the Cooling full-load air
volume rate and the fan speed or control settings to meet each test
procedure requirement:
a. For all ducted blower coil systems, except those having a
constant-air-volume-rate indoor blower:
Step (1) Operate the unit under conditions specified for the A
(for single-stage units) or A2 test using the certified
fan speed or controls settings, and adjust the exhaust fan of the
airflow measuring apparatus to achieve the certified Cooling full-
load air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this external static pressure is equal to or greater
than the applicable minimum external static pressure cited in Table
3, the pressure requirement is satisfied; proceed to step 7 of this
section. If this external static pressure is not equal to or greater
than the applicable minimum external static pressure cited in Table
3, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until either
(i) The applicable Table 3 minimum is equaled or
[[Page 58225]]
(ii) The measured air volume rate equals 90 percent or less of
the Cooling full-load air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning above, at
step 1 of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until the applicable
Table 3 minimum is equaled; proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the Cooling full-load air volume rate.
Use the final fan speed or control settings for all tests that use
the Cooling full-load air volume rate.
b. For ducted blower coil systems with a constant-air-volume-
rate indoor blower. For all tests that specify the Cooling full-load
air volume rate, obtain an external static pressure as close to (but
not less than) the applicable Table 3 value that does not cause
automatic shutdown of the indoor blower or air volume rate variation
QVar, defined as follows, greater than 10 percent.
[GRAPHIC] [TIFF OMITTED] TP24AU16.014
Where:
Qmax = maximum measured airflow value
Qmin = minimum measured airflow value
QVar = airflow variance, percent
Additional test steps as described in section 3.3.e of this
appendix are required if the measured external static pressure
exceeds the target value by more than 0.03 inches of water.
c. For coil-only indoor units. For the A or A2 Test,
(exclusively), the pressure drop across the indoor coil assembly
must not exceed 0.30 inches of water. If this pressure drop is
exceeded, reduce the air volume rate until the measured pressure
drop equals the specified maximum. Use this reduced air volume rate
for all tests that require the Cooling full-load air volume rate.
Table 3--Minimum External Static Pressure for Ducted Blower Coil Systems
------------------------------------------------------------------------
Minimum
external
Product variety static
pressure (in.
wc.)
------------------------------------------------------------------------
Conventional (i.e., all central air conditioners and 0.50
heat pumps not otherwise listed in this table).........
Ceiling-mount and Wall-mount............................ 0.30
Mobile Home............................................. 0.30
Low Static.............................................. 0.10
Mid Static.............................................. 0.30
Small Duct, High Velocity............................... 1.15
Space Constrained....................................... 0.30
------------------------------------------------------------------------
\1\ For ducted units tested without an air filter installed, increase
the applicable tabular value by 0.08 inches of water.
\2\ See section 1.2, Definitions, to determine for which Table 3 product
variety and associated minimum external static pressure requirement
equipment qualifies.
\3\ If a closed-loop, air-enthalpy test apparatus is used on the indoor
side, limit the resistance to airflow on the inlet side of the indoor
blower coil to a maximum value of 0.1 inch of water.
d. For ducted systems having multiple indoor blowers within a
single indoor section, obtain the full-load air volume rate with all
indoor blowers operating unless prevented by the controls of the
unit. In such cases, turn on the maximum number of indoor blowers
permitted by the unit's controls. Where more than one option exists
for meeting this ``on'' indoor blower requirement, which indoor
blower(s) are turned on must match that specified in the
certification report. Conduct section 3.1.4.1.1 setup steps for each
indoor blower separately. If two or more indoor blowers are
connected to a common duct as per section 2.4.1 of this appendix,
temporarily divert their air volume to the test room when confirming
or adjusting the setup configuration of individual indoor blowers.
The allocation of the system's full-load air volume rate assigned to
each ``on'' indoor blower must match that specified by the
manufacturer in the certification report.
3.1.4.1.2. Cooling Full-Load Air Volume Rate for Non-Ducted Units
For non-ducted units, the Cooling full-load air volume rate is
the air volume rate that results during each test when the unit is
operated at an external static pressure of zero inches of water.
3.1.4.2 Cooling Minimum Air Volume Rate
Identify the certified cooling minimum air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified cooling minimum air volume rate, use the final
indoor blower control settings as determined when setting the
cooling full-load air volume rate, and readjust the exhaust fan of
the airflow measuring apparatus if necessary to reset to the cooling
full load air volume obtained in section 3.1.4.1 of this appendix.
Otherwise, calculate the target external static pressure and follow
instructions a, b, c, d, or e below. The target external static
pressure, [Delta]Pst_i, for any test ``i'' with a
specified air volume rate not equal to the Cooling full-load air
volume rate is determined as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.015
Where:
[Delta]Pst_i = target minimum external static
pressure for test i;
[Delta]Pst_full = minimum external static pressure
for test A or A2 (Table 3);
Qi = air volume rate for test i; and
Qfull = Cooling full-load air volume rate as
measured after setting and/or adjustment as described in section
3.1.4.1.1 of this appendix.
a. For a ducted blower coil system without a constant-air-volume
indoor blower, adjust for external static pressure as follows:
Step (1) Operate the unit under conditions specified for the
B1 test using the certified fan speed or controls
settings, and adjust the exhaust fan of the airflow measuring
apparatus to achieve the certified cooling minimum air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this pressure is equal to or greater than the
minimum external static pressure computed above, the pressure
requirement is satisfied; proceed to step 7 of this section. If this
pressure is not equal to or greater than the minimum external static
pressure computed above, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until either
(i) The pressure is equal to the minimum external static
pressure computed above or
(ii) The measured air volume rate equals 90 percent or less of
the cooling minimum air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning above, at
step 1 of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until it equals the
minimum external static pressure computed above; proceed to step 7
of this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the cooling minimum air volume rate. Use
the final fan speed or control settings for all tests that use the
cooling minimum air volume rate.
b. For ducted units with constant-air-volume indoor blowers,
conduct all tests that specify the cooling minimum air volume rate--
(i.e., the A1, B1, C1,
F1, and G1 Tests)--at an external static
pressure that does not cause an automatic shutdown of the indoor
blower or air volume rate variation QVar, defined in
section 3.1.4.1.1.b of this appendix, greater than 10 percent, while
being as close to, but not less than the target minimum external
static pressure. Additional test steps as described in section 3.3.e
of this appendix are required if the measured
[[Page 58226]]
external static pressure exceeds the target value by more than 0.03
inches of water.
c. For ducted two-capacity coil-only systems, the cooling
minimum air volume rate is the higher of--
(1) The rate specified by the installation instructions included
with the unit by the manufacturer; or
(2) 75 percent of the cooling full-load air volume rate. During
the laboratory tests on a coil-only (fanless) system, obtain this
cooling minimum air volume rate regardless of the pressure drop
across the indoor coil assembly.
d. For non-ducted units, the cooling minimum air volume rate is
the air volume rate that results during each test when the unit
operates at an external static pressure of zero inches of water and
at the indoor blower setting used at low compressor capacity (two-
capacity system) or minimum compressor speed (variable-speed
system). For units having a single-speed compressor and a variable-
speed variable-air-volume-rate indoor blower, use the lowest fan
setting allowed for cooling.
e. For ducted systems having multiple indoor blowers within a
single indoor section, operate the indoor blowers such that the
lowest air volume rate allowed by the unit's controls is obtained
when operating the lone single-speed compressor or when operating at
low compressor capacity while meeting the requirements of section
2.2.3.2 of this appendix for the minimum number of blowers that must
be turned off. Using the target external static pressure and the
certified air volume rates, follow the procedures described in
section 3.1.4.2.a of this appendix if the indoor blowers are not
constant-air-volume indoor blowers or as described in section
3.1.4.2.b of this appendix if the indoor blowers are not constant-
air-volume indoor blowers. The sum of the individual ``on'' indoor
blowers' air volume rates is the cooling minimum air volume rate for
the system.
3.1.4.3 Cooling Intermediate Air Volume Rate
Identify the certified cooling intermediate air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified cooling intermediate air volume rate, use the final
indoor blower control settings as determined when setting the
cooling full load air volume rate, and readjust the exhaust fan of
the airflow measuring apparatus if necessary to reset to the cooling
full load air volume obtained in section 3.1.4.1 of this appendix.
Otherwise, calculate target minimum external static pressure as
described in section 3.1.4.2 of this appendix, and set the air
volume rate as follows.
a. For a ducted blower coil system without a constant-air-volume
indoor blower, adjust for external static pressure as described in
section 3.1.4.2.a of this appendix for cooling minimum air volume
rate.
b. For a ducted blower coil system with a constant-air-volume
indoor blower, conduct the EV Test at an external static
pressure that does not cause an automatic shutdown of the indoor
blower or air volume rate variation QVar, defined in
section 3.1.4.1.1.b of this appendix, greater than 10 percent, while
being as close to, but not less than the target minimum external
static pressure. Additional test steps as described in section 3.3.e
of this appendix are required if the measured external static
pressure exceeds the target value by more than 0.03 inches of water.
c. For non-ducted units, the cooling intermediate air volume
rate is the air volume rate that results when the unit operates at
an external static pressure of zero inches of water and at the fan
speed selected by the controls of the unit for the EV
Test conditions.
3.1.4.4 Heating Full-Load Air Volume Rate
3.1.4.4.1. Ducted Heat Pumps Where the Heating and Cooling Full-Load
Air Volume Rates Are the Same
a. Use the Cooling full-load air volume rate as the heating
full-load air volume rate for:
(1) Ducted blower coil system heat pumps that do not have a
constant-air-volume indoor blower, and that operate at the same
airflow-control setting during both the A (or A2) and the
H1 (or H12) Tests;
(2) Ducted blower coil system heat pumps with constant-air-flow
indoor blowers that provide the same airflow for the A (or
A2) and the H1 (or H12) Tests; and
(3) Ducted heat pumps that are tested with a coil-only indoor
unit (except two-capacity northern heat pumps that are tested only
at low capacity cooling--see section 3.1.4.4.2 of this appendix).
b. For heat pumps that meet the above criteria ``1'' and ``3,''
no minimum requirements apply to the measured external or internal,
respectively, static pressure. Use the final indoor blower control
settings as determined when setting the Cooling full-load air volume
rate, and readjust the exhaust fan of the airflow measuring
apparatus if necessary to reset to the cooling full-load air volume
obtained in section 3.1.4.1 of this appendix. For heat pumps that
meet the above criterion ``2,'' test at an external static pressure
that does not cause an automatic shutdown of the indoor blower or
air volume rate variation QVar, defined in section
3.1.4.1.1.b of this appendix, greater than 10 percent, while being
as close to, but not less than, the same Table 3 minimum external
static pressure as was specified for the A (or A2)
cooling mode test. Additional test steps as described in section
3.9.1.c of this appendix are required if the measured external
static pressure exceeds the target value by more than 0.03 inches of
water.
3.1.4.4.2. Ducted Heat Pumps Where the Heating and Cooling Full-Load
Air Volume Rates Are Different Due to Changes in Indoor Blower
Operation, i.e. Speed Adjustment by the System Controls
Identify the certified heating full-load air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified heating full-load air volume rate, use the final
indoor blower control settings as determined when setting the
cooling full-load air volume rate, and readjust the exhaust fan of
the airflow measuring apparatus if necessary to reset to the cooling
full-load air volume obtained in section 3.1.4.1 of this appendix.
Otherwise, calculate the target minimum external static pressure as
described in section 3.1.4.2 of this appendix and set the air volume
rate as follows.
a. For ducted blower coil system heat pumps that do not have a
constant-air-volume indoor blower, adjust for external static
pressure as described in section 3.1.4.2.a of this appendix for
cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor
blowers installed, conduct all tests that specify the heating full-
load air volume rate at an external static pressure that does not
cause an automatic shutdown of the indoor blower or air volume rate
variation QVar, defined in section 3.1.4.1.1.b of this
appendix, greater than 10 percent, while being as close to, but not
less than the target minimum external static pressure. Additional
test steps as described in section 3.9.1.c of this appendix are
required if the measured external static pressure exceeds the target
value by more than 0.03 inches of water.
c. When testing ducted, two-capacity blower coil system northern
heat pumps (see section 1.2 of this appendix, Definitions), use the
appropriate approach of the above two cases. For coil-only system
northern heat pumps, the heating full-load air volume rate is the
lesser of the rate specified by the manufacturer in the installation
instructions included with the unit or 133 percent of the cooling
full-load air volume rate. For this latter case, obtain the heating
full-load air volume rate regardless of the pressure drop across the
indoor coil assembly.
d. For ducted systems having multiple indoor blowers within a
single indoor section, obtain the heating full-load air volume rate
using the same ``on'' indoor blowers as used for the Cooling full-
load air volume rate. Using the target external static pressure and
the certified air volume rates, follow the procedures as described
in section 3.1.4.4.2.a of this appendix if the indoor blowers are
not constant-air-volume indoor blowers or as described in section
3.1.4.4.2.b of this appendix if the indoor blowers are constant-air-
volume indoor blowers. The sum of the individual ``on'' indoor
blowers' air volume rates is the heating full-load air volume rate
for the system.
3.1.4.4.3. Ducted Heating-Only Heat Pumps
Identify the certified heating full-load air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified heating full-load air volume rate, use a value equal
to the certified heating capacity of the unit times 400 scfm per
12,000 Btu/h. If there are no instructions for setting fan speed or
controls, use the as-shipped settings.
a. For all ducted heating-only blower coil system heat pumps,
except those having a constant-air-volume-rate indoor blower.
Conduct the following steps only during the first test, the H1 or
H12 test:
Step (1) Adjust the exhaust fan of the airflow measuring
apparatus to achieve the certified heating full-load air volume
rate.
Step (2) Measure the external static pressure.
Step (3) If this pressure is equal to or greater than the Table
3 minimum external static pressure that applies given the heating-
only heat pump's rated heating capacity, the pressure requirement is
satisfied; proceed to step 7 of this section. If this pressure is
not
[[Page 58227]]
equal to or greater than the applicable Table 3 minimum external
static pressure, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until either--
(i) The pressure is equal to the applicable Table 3 minimum
external static pressure; or (ii) The measured air volume rate
equals 90 percent or less of the heating full-load air volume rate,
whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning above, at
step 1 of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until it equals the
applicable Table 3 minimum external static pressure; proceed to step
7 of this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the heating full-load air volume rate.
Use the final fan speed or control settings for all tests that use
the heating full-load air volume rate.
b. For ducted heating-only blower coil system heat pumps having
a constant-air-volume-rate indoor blower. For all tests that specify
the heating full-load air volume rate, obtain an external static
pressure that does not cause an automatic shutdown of the indoor
blower or air volume rate variation QVar, defined in
section 3.1.4.1.1.b of this section, greater than 10 percent, while
being as close to, but not less than, the applicable Table 3
minimum. Additional test steps as described in section 3.9.1.c of
this appendix are required if the measured external static pressure
exceeds the target value by more than 0.03 inches of water.
c. For ducted heating-only coil-only system heat pumps in the H1
or H12 Test, (exclusively), the pressure drop across the
indoor coil assembly must not exceed 0.30 inches of water. If this
pressure drop is exceeded, reduce the air volume rate until the
measured pressure drop equals the specified maximum. Use this
reduced air volume rate for all tests that require the heating full-
load air volume rate.
3.1.4.4.4 Non-Ducted Heat Pumps, Including Non-Ducted Heating-Only Heat
Pumps
For non-ducted heat pumps, the heating full-load air volume rate
is the air volume rate that results during each test when the unit
operates at an external static pressure of zero inches of water.
3.1.4.5 Heating Minimum Air Volume Rate
3.1.4.5.1. Ducted Heat Pumps Where the Heating and Cooling Minimum Air
Volume Rates are the Same
a. Use the cooling minimum air volume rate as the heating
minimum air volume rate for:
(1) Ducted blower coil system heat pumps that do not have a
constant-air-volume indoor blower, and that operates at the same
airflow-control setting during both the A1 and the
H11 tests;
(2) Ducted blower coil system heat pumps with constant-air-flow
indoor blowers installed that provide the same airflow for the
A1 and the H11 Tests; and
(3) Ducted coil-only system heat pumps.
b. For heat pumps that meet the above criteria ``1'' and ``3,''
no minimum requirements apply to the measured external or internal,
respectively, static pressure. Use the final indoor blower control
settings as determined when setting the cooling minimum air volume
rate, and readjust the exhaust fan of the airflow measuring
apparatus if necessary to reset to the cooling minimum air volume
rate obtained in section 3.1.4.2 of this appendix. For heat pumps
that meet the above criterion ``2,'' test at an external static
pressure that does not cause an automatic shutdown of the indoor
blower or air volume rate variation QVar, defined in
section 3.1.4.1.1.b, greater than 10 percent, while being as close
to, but not less than, the same target minimum external static
pressure as was specified for the A1 cooling mode test.
Additional test steps as described in section 3.9.1.c of this
appendix are required if the measured external static pressure
exceeds the target value by more than 0.03 inches of water.
3.1.4.5.2. Ducted Heat Pumps Where the Heating and Cooling Minimum Air
Volume Rates are Different Due to Indoor Blower Operation, i.e. Speed
Adjustment by the System Controls
Identify the certified heating minimum air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified heating minimum air volume rate, use the final
indoor blower control settings as determined when setting the
cooling minimum air volume rate, and readjust the exhaust fan of the
airflow measuring apparatus if necessary to reset to the cooling
minimum air volume obtained in section 3.1.4.2 of this appendix.
Otherwise, calculate the target minimum external static pressure as
described in section 3.1.4.2 of this appendix.
a. For ducted blower coil system heat pumps that do not have a
constant-air-volume indoor blower, adjust for external static
pressure as described in section 3.1.4.2.a of this appendix for
cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor
blowers installed, conduct all tests that specify the heating
minimum air volume rate--(i.e., the H01, H11,
H21, and H31 Tests)--at an external static
pressure that does not cause an automatic shutdown of the indoor
blower while being as close to, but not less than the air volume
rate variation QVar, defined in section 3.1.4.1.1.b of
this appendix, greater than 10 percent, while being as close to, but
not less than the target minimum external static pressure.
Additional test steps as described in section 3.9.1.c of this
appendix are required if the measured external static pressure
exceeds the target value by more than 0.03 inches of water.
c. For ducted two-capacity blower coil system northern heat
pumps, use the appropriate approach of the above two cases.
d. For ducted two-capacity coil-only system heat pumps, use the
cooling minimum air volume rate as the heating minimum air volume
rate. For ducted two-capacity coil-only system northern heat pumps,
use the cooling full-load air volume rate as the heating minimum air
volume rate. For ducted two-capacity heating-only coil-only system
heat pumps, the heating minimum air volume rate is the higher of the
rate specified by the manufacturer in the test setup instructions
included with the unit or 75 percent of the heating full-load air
volume rate. During the laboratory tests on a coil-only system,
obtain the heating minimum air volume rate without regard to the
pressure drop across the indoor coil assembly.
e. For non-ducted heat pumps, the heating minimum air volume
rate is the air volume rate that results during each test when the
unit operates at an external static pressure of zero inches of water
and at the indoor blower setting used at low compressor capacity
(two-capacity system) or minimum compressor speed (variable-speed
system). For units having a single-speed compressor and a variable-
speed, variable-air-volume-rate indoor blower, use the lowest fan
setting allowed for heating.
f. For ducted systems with multiple indoor blowers within a
single indoor section, obtain the heating minimum air volume rate
using the same ``on'' indoor blowers as used for the cooling minimum
air volume rate. Using the target external static pressure and the
certified air volume rates, follow the procedures as described in
section 3.1.4.5.2.a of this appendix if the indoor blowers are not
constant-air-volume indoor blowers or as described in section
3.1.4.5.2.b of this appendix if the indoor blowers are constant-air-
volume indoor blowers. The sum of the individual ``on'' indoor
blowers' air volume rates is the heating full-load air volume rate
for the system.
3.1.4.6 Heating Intermediate Air Volume Rate
Identify the certified heating intermediate air volume rate and
certified instructions for setting fan speed or controls. If there
is no certified heating intermediate air volume rate, use the final
indoor blower control settings as determined when setting the
heating full-load air volume rate, and readjust the exhaust fan of
the airflow measuring apparatus if necessary to reset to the cooling
full-load air volume obtained in section 3.1.4.2 of this appendix.
Calculate the target minimum external static pressure as described
in section 3.1.4.2 of this appendix.
a. For ducted blower coil system heat pumps that do not have a
constant-air-volume indoor blower, adjust for external static
pressure as described in section 3.1.4.2.a of this appendix for
cooling minimum air volume rate.
b. For ducted heat pumps tested with constant-air-volume indoor
blowers installed, conduct the H2V Test at an external
static pressure that does not cause an automatic shutdown of the
indoor blower or air volume rate variation QVar, defined
in section 3.1.4.1.1.b of this appendix, greater than 10
[[Page 58228]]
percent, while being as close to, but not less than the target
minimum external static pressure. Additional test steps as described
in section 3.9.1.c of this appendix are required if the measured
external static pressure exceeds the target value by more than 0.03
inches of water.
c. For non-ducted heat pumps, the heating intermediate air
volume rate is the air volume rate that results when the heat pump
operates at an external static pressure of zero inches of water and
at the fan speed selected by the controls of the unit for the
H2V Test conditions.
3.1.4.7 Heating Nominal Air Volume Rate
The manufacturer must specify the heating nominal air volume
rate and the instructions for setting fan speed or controls.
Calculate target minimum external static pressure as described in
section 3.1.4.2 of this appendix. Make adjustments as described in
section 3.14.6 of this appendix for heating intermediate air volume
rate so that the target minimum external static pressure is met or
exceeded.
3.1.5 Indoor Test Room Requirement When the Air Surrounding the Indoor
Unit is Not Supplied From the Same Source as the Air Entering the
Indoor Unit
If using a test set-up where air is ducted directly from the air
reconditioning apparatus to the indoor coil inlet (see Figure 2,
Loop Air-Enthalpy Test Method Arrangement, of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3)), maintain the dry bulb
temperature within the test room within 5.0[emsp14][deg]F of the applicable sections 3.2 and 3.6 dry
bulb temperature test condition for the air entering the indoor
unit. Dew point must be within 2[emsp14][deg]F of the required inlet
conditions.
3.1.6 Air Volume Rate Calculations
For all steady-state tests and for frost accumulation (H2,
H21, H22, H2V) tests, calculate the
air volume rate through the indoor coil as specified in sections
7.7.2.1 and 7.7.2.2 of ANSI/ASHRAE 37-2009. When using the outdoor
air enthalpy method, follow sections 7.7.2.1 and 7.7.2.2 of ANSI/
ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3) to
calculate the air volume rate through the outdoor coil. To express
air volume rates in terms of standard air, use:
[GRAPHIC] [TIFF OMITTED] TP24AU16.016
Where:
Vis = air volume rate of standard (dry) air, (ft\3\/
min)da
Vimx = air volume rate of the air-water vapor mixture,
(ft\3\/min)mx
vn' = specific volume of air-water vapor mixture at the
nozzle, ft\3\ per lbm of the air-water vapor mixture
Wn = humidity ratio at the nozzle, lbm of water vapor per
lbm of dry air
0.075 = the density associated with standard (dry) air, (lbm/ft\3\)
vn = specific volume of the dry air portion of the
mixture evaluated at the dry-bulb temperature, vapor content, and
barometric pressure existing at the nozzle, ft\3\ per lbm of dry
air.
(Note: In the first printing of ANSI/ASHRAE 37-2009, the second
IP equation for
[GRAPHIC] [TIFF OMITTED] TP24AU16.017
3.1.7 Test Sequence
Before making test measurements used to calculate performance,
operate the equipment for the ``break-in'' period specified in the
certification report, which may not exceed 20 hours. Each compressor
of the unit must undergo this ``break-in'' period. When testing a
ducted unit (except if a heating-only heat pump), conduct the A or
A2 Test first to establish the cooling full-load air
volume rate. For ducted heat pumps where the heating and cooling
full-load air volume rates are different, make the first heating
mode test one that requires the heating full-load air volume rate.
For ducted heating-only heat pumps, conduct the H1 or H12
Test first to establish the heating full-load air volume rate. When
conducting a cyclic test, always conduct it immediately after the
steady-state test that requires the same test conditions. For
variable-speed systems, the first test using the cooling minimum air
volume rate should precede the EV Test, and the first
test using the heating minimum air volume rate must precede the
H2V Test. The test laboratory makes all other decisions
on the test sequence.
3.1.8 Requirement for the Air Temperature Distribution Leaving the
Indoor Coil
For at least the first cooling mode test and the first heating
mode test, monitor the temperature distribution of the air leaving
the indoor coil using the grid of individual sensors described in
sections 2.5 and 2.5.4 of this appendix. For the 30-minute data
collection interval used to determine capacity, the maximum spread
among the outlet dry bulb temperatures from any data sampling must
not exceed 1.5[emsp14][deg]F. Install the mixing devices described
in section 2.5.4.2 of this appendix to minimize the temperature
spread.
3.1.9 Requirement for the Air Temperature Distribution Entering the
Outdoor Coil
Monitor the temperatures of the air entering the outdoor coil
using air sampling devices and/or temperature sensor grids,
maintaining the required tolerances, if applicable, as described in
section 2.11 of this appendix.
3.1.10 Control of Auxiliary Resistive Heating Elements
Except as noted, disable heat pump resistance elements used for
heating indoor air at all times, including during defrost cycles and
if they are normally regulated by a heat comfort controller. For
heat pumps equipped with a heat comfort controller, enable the heat
pump resistance elements only during the below-described, short
test. For single-speed heat pumps covered under section 3.6.1 of
this appendix, the short test follows the H1 or, if conducted, the
H1C Test. For two-capacity heat pumps and heat pumps covered under
section 3.6.2 of this appendix, the short test follows the
H12 Test. Set the heat comfort controller to provide the
maximum supply air temperature. With the heat pump operating and
while maintaining the heating full-load air volume rate, measure the
temperature of the air leaving the indoor-side beginning 5 minutes
after activating the heat comfort controller. Sample the outlet dry-
bulb temperature at regular intervals that span 5 minutes or less.
Collect data for 10 minutes, obtaining at least 3 samples. Calculate
the average outlet temperature over the 10-minute interval,
TCC.
3.2 Cooling Mode Tests for Different Types of Air Conditioners and Heat
Pumps
3.2.1 Tests for a System Having a Single-Speed Compressor and Fixed
Cooling Air Volume Rate
This set of tests is for single-speed-compressor units that do
not have a cooling minimum air volume rate or a cooling intermediate
air volume rate that is different than the cooling full load air
volume rate. Conduct two steady-state wet coil tests, the A and B
Tests. Use the two optional dry-coil tests, the steady-state C Test
and the cyclic D Test, to determine the cooling mode cyclic
degradation coefficient, CD\c\. If the two optional tests
are conducted but yield a tested CD\c\ that exceeds the
default CD\c\ or if the two optional tests are not
conducted, assign CD\c\ the default value of 0.25 (for
outdoor units with no match) or 0.2 (for all other systems). Table 4
specifies test conditions for these four tests.
[[Page 58229]]
Table 4--Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed Cooling Air Volume
Rate
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Cooling air
Test description ---------------------------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A Test--required (steady, wet 80 67 95 \1\ 75 Cooling full-
coil). load. \2\
B Test--required (steady, wet 80 67 82 \1\ 65 Cooling full-
coil). load. \2\
C Test--optional (steady, dry 80 (\3\) 82 .............. Cooling full-
coil). load. \2\
D Test--optional (cyclic, dry 80 (\3\) 82 .............. (\4\).
coil).
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. (It is
recommended that an indoor wet-bulb temperature of 57[emsp14][deg]F or less be used.)
\4\ Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the C Test.
3.2.2 Tests for a Unit Having a Single-Speed Compressor Where the
Indoor Section Uses a Single Variable-Speed Variable-Air-Volume Rate
Indoor Blower or Multiple Indoor Blowers
3.2.2.1 Indoor Blower Capacity Modulation That Correlates With the
Outdoor Dry Bulb Temperature or Systems With a Single Indoor Coil but
Multiple Indoor Blowers
Conduct four steady-state wet coil tests: The A2,
A1, B2, and B1 tests. Use the two
optional dry-coil tests, the steady-state C1 test and the
cyclic D1 test, to determine the cooling mode cyclic
degradation coefficient, CD\c\. If the two optional tests
are conducted but yield a tested CD\c\ that exceeds the
default CD\c\ or if the two optional tests are not
conducted, assign CD\c\ the default value of 0.2.
3.2.2.2 Indoor Blower Capacity Modulation Based on Adjusting the
Sensible to Total (S/T) Cooling Capacity Ratio
The testing requirements are the same as specified in section
3.2.1 of this appendix and Table 4. Use a cooling full-load air
volume rate that represents a normal installation. If performed,
conduct the steady-state C Test and the cyclic D Test with the unit
operating in the same S/T capacity control mode as used for the B
Test.
Table 5--Cooling Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.2.2.1
Indoor Unit Requirements
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Cooling air
Test description ---------------------------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet 80 67 95 \1\ 75 Cooling full-
coil). load.\2\
A1 Test--required (steady, wet 80 67 95 \1\ 75 Cooling
coil). minimum.\3\
B2 Test--required (steady, wet 80 67 82 \1\ 65 Cooling full-
coil). load.\2\
B1 Test--required (steady, wet 80 67 82 \1\ 65 Cooling
coil). minimum.\3\
C1 Test \4\--optional (steady, 80 (\4\) 82 .............. Cooling
dry coil). minimum.\3\
D1 Test \4\--optional (cyclic, 80 (\4\) 82 .............. (\5\).
dry coil).
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ Defined in section 3.1.4.2 of this appendix.
\4\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. (It is
recommended that an indoor wet-bulb temperature of 57[emsp14][deg]F or less be used.)
\5\ Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the C1 Test.
3.2.3 Tests for a Unit Having a Two-Capacity Compressor (See Section
1.2 of This Appendix, Definitions)
a. Conduct four steady-state wet coil tests: the A2,
B2, B1, and F1 Tests. Use the two
optional dry-coil tests, the steady-state C1 Test and the
cyclic D1 Test, to determine the cooling-mode cyclic-
degradation coefficient, CD\c\. If the two optional tests
are conducted but yield a tested CD\c\ that exceeds the
default CD\c\ or if the two optional tests are not
conducted, assign CD\c\ the default value of 0.2. Table 6
specifies test conditions for these six tests.
b. For units having a variable speed indoor blower that is
modulated to adjust the sensible to total (S/T) cooling capacity
ratio, use cooling full-load and cooling minimum air volume rates
that represent a normal installation. Additionally, if conducting
the dry-coil tests, operate the unit in the same S/T capacity
control mode as used for the B1 Test.
c. Test two-capacity, northern heat pumps (see section 1.2 of
this appendix, Definitions) in the same way as a single speed heat
pump with the unit operating exclusively at low compressor capacity
(see section 3.2.1 of this appendix and Table 4).
d. If a two-capacity air conditioner or heat pump locks out low-
capacity operation at higher outdoor temperatures, then use the two
dry-coil tests, the steady-state C2 Test and the cyclic
D2 Test, to determine the cooling-mode cyclic-degradation
coefficient that only applies to on/off cycling from high capacity,
CD\c\(k=2). If the two optional tests are conducted but
yield a tested CD\c\(k = 2) that exceeds the default
CD\c\(k = 2) or if the two optional tests are not
conducted, assign CD\c\(k = 2) the default value. The
default CD\c\(k=2) is the same value as determined or
assigned for the low-capacity cyclic-degradation coefficient,
CD\c\ [or equivalently, CD\c\(k=1)].
[[Page 58230]]
Table 6--Cooling Mode Test Conditions for Units Having a Two-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor capacity Cooling air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet coil). 80 67 95 \1\ 75 High.................... Cooling Full-Load.\2\
B2 Test--required (steady, wet coil). 80 67 82 \1\ 65 High.................... Cooling Full-Load.\2\
B1 Test--required (steady, wet coil). 80 67 82 \1\ 65 Low..................... Cooling Minimum.\3\
C2 Test--optional (steady, dry-coil). 80 (\4\) 82 .............. High.................... Cooling Full-Load.\2\
D2 Test--optional (cyclic, dry-coil). 80 (\4\) 82 .............. High.................... (\5\)
C1 Test--optional (steady, dry-coil). 80 (\4\) 82 .............. Low..................... Cooling Minimum.\3\
D1 Test--optional (cyclic, dry-coil). 80 (\4\) 82 .............. Low..................... (\6\)
F1 Test--required (steady, wet coil). 80 67 67 \1\53.5 Low..................... Cooling Minimum.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ Defined in section 3.1.4.2 of this appendix.
\4\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet-bulb
temperature of 57[emsp14][deg]F or less.
\5\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the C2 Test.
\6\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the C1 Test.
3.2.4 Tests for a Unit Having a Variable-Speed Compressor
a. Conduct five steady-state wet coil tests: The A2,
EV, B2, B1, and F1
Tests. Use the two optional dry-coil tests, the steady-state
G1 Test and the cyclic I1 Test, to determine
the cooling mode cyclic degradation coefficient, CD\c\.
If the two optional tests are conducted but yield a tested
CD\c\ that exceeds the default CD\c\ or if the
two optional tests are not conducted, assign CD\c\ the
default value of 0.25. Table 7 specifies test conditions for these
seven tests. The compressor shall operate at the same cooling full
speed, measured by RPM or power input frequency (Hz), for both the
A2 and B2 tests. The compressor shall operate
at the same cooling minimum speed, measured by RPM or power input
frequency (Hz), for the B1, F1, G1,
and I1 tests. Determine the cooling intermediate
compressor speed cited in Table 7 using:
Cooling intermediate speed
[GRAPHIC] [TIFF OMITTED] TP24AU16.018
where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
b. For units that modulate the indoor blower speed to adjust the
sensible to total (S/T) cooling capacity ratio, use cooling full-
load, cooling intermediate, and cooling minimum air volume rates
that represent a normal installation. Additionally, if conducting
the dry-coil tests, operate the unit in the same S/T capacity
control mode as used for the F1 Test.
c. For multiple-split air conditioners and heat pumps (except
where noted), the following procedures supersede the above
requirements: For all Table 7 tests specified for a minimum
compressor speed, turn off at least one indoor unit. The
manufacturer shall designate the particular indoor unit(s) that is
turned off. The manufacturer must also specify the compressor speed
used for the Table 7 EV Test, a cooling-mode intermediate
compressor speed that falls within \1/4\ and \3/4\ of the difference
between the full and minimum cooling-mode speeds. The manufacturer
should prescribe an intermediate speed that is expected to yield the
highest EER for the given EV Test conditions and
bracketed compressor speed range. The manufacturer can designate
that one or more indoor units are turned off for the EV
Test.
Table 7--Cooling Mode Test Condition for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor speed Cooling air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet coil). 80 67 95 \1\ 75 Cooling Full............ Cooling Full-Load.\2\
B2 Test--required (steady, wet coil). 80 67 82 \1\ 65 Cooling Full............ Cooling Full-Load.\2\
EV Test--required (steady, wet coil). 80 67 87 \1\ 69 Cooling Intermediate.... Cooling
Intermediate.\3\
B1 Test--required (steady, wet coil). 80 67 82 \1\ 65 Cooling Minimum......... Cooling Minimum.\4\
[[Page 58231]]
F1 Test--required (steady, wet coil). 80 67 67 \1\ 53.5 Cooling Minimum......... Cooling Minimum.\4\
G1 Test \5\--optional (steady, dry- 80 (\6\) 67 .............. Cooling Minimum......... Cooling Minimum.\4\
coil).
I1 Test \5\--optional (cyclic, dry- 80 (\6\) 67 .............. Cooling Minimum......... (\6\)
coil).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ Defined in section 3.1.4.3 of this appendix.
\4\ Defined in section 3.1.4.2 of this appendix.
\5\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet bulb
temperature of 57[emsp14][deg]F or less.
\6\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the G1 Test.
3.2.5 Cooling Mode Tests for Northern Heat Pumps With Triple-Capacity
Compressors
Test triple-capacity, northern heat pumps for the cooling mode
in the same way as specified in section 3.2.3 of this appendix for
units having a two-capacity compressor.
3.2.6 Tests for an Air Conditioner or Heat Pump Having a Single Indoor
Unit Having Multiple Indoor Blowers and Offering Two Stages of
Compressor Modulation
Conduct the cooling mode tests specified in section 3.2.3 of
this appendix.
3.3 Test Procedures for Steady-State Wet Coil Cooling Mode Tests (the
A, A2, A1, B, B2, B1,
EV, and F1 Tests)
a. For the pretest interval, operate the test room
reconditioning apparatus and the unit to be tested until maintaining
equilibrium conditions for at least 30 minutes at the specified
section 3.2 test conditions. Use the exhaust fan of the airflow
measuring apparatus and, if installed, the indoor blower of the test
unit to obtain and then maintain the indoor air volume rate and/or
external static pressure specified for the particular test.
Continuously record (see section 1.2 of this appendix, Definitions):
(1) The dry-bulb temperature of the air entering the indoor
coil,
(2) The water vapor content of the air entering the indoor coil,
(3) The dry-bulb temperature of the air entering the outdoor
coil, and
(4) For the section 2.2.4 of this appendix cases where its
control is required, the water vapor content of the air entering the
outdoor coil.
Refer to section 3.11 of this appendix for additional
requirements that depend on the selected secondary test method.
b. After satisfying the pretest equilibrium requirements, make
the measurements specified in Table 3 of ANSI/ASHRAE 37-2009 for the
indoor air enthalpy method and the user-selected secondary method.
Make said Table 3 measurements at equal intervals that span 5
minutes or less. Continue data sampling until reaching a 30-minute
period (e.g., seven consecutive 5-minute samples) where the test
tolerances specified in Table 8 are satisfied. For those
continuously recorded parameters, use the entire data set from the
30-minute interval to evaluate Table 8 compliance. Determine the
average electrical power consumption of the air conditioner or heat
pump over the same 30-minute interval.
c. Calculate indoor-side total cooling capacity and sensible
cooling capacity as specified in sections 7.3.3.1 and 7.3.3.3 of
ANSI/ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3). To
calculate capacity, use the averages of the measurements (e.g. inlet
and outlet dry bulb and wet bulb temperatures measured at the
psychrometers) that are continuously recorded for the same 30-minute
interval used as described above to evaluate compliance with test
tolerances. Do not adjust the parameters used in calculating
capacity for the permitted variations in test conditions. Evaluate
air enthalpies based on the measured barometric pressure. Use the
values of the specific heat of air given in section 7.3.3.1 of ANSI/
ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3) for
calculation of the sensible cooling capacities. Assign the average
total space cooling capacity, average sensible cooling capacity, and
electrical power consumption over the 30-minute data collection
interval to the variables Qc\k\(T), Qsc\k\(T)
and Ec\k\(T), respectively. For these three variables,
replace the ``T'' with the nominal outdoor temperature at which the
test was conducted. The superscript k is used only when testing
multi-capacity units. Use the superscript k=2 to denote a test with
the unit operating at high capacity or full speed, k=1 to denote low
capacity or minimum speed, and k=v to denote the intermediate speed.
d. For mobile home ducted coil-only system tests, decrease
Qc\k\(T) by
[GRAPHIC] [TIFF OMITTED] TP24AU16.019
where Vis is the average measured indoor air volume rate
expressed in units of cubic feet per minute of standard air (scfm).
For non-mobile home ducted coil-only system tests, decrease
Qc\k\(T) by
[GRAPHIC] [TIFF OMITTED] TP24AU16.020
where Vis is the average measured indoor air volume
rate expressed in units of cubic feet per minute of standard air
(scfm).
Table 8--Test Operating and Test Condition Tolerances for Section 3.3
Steady-State Wet Coil Cooling Mode Tests and Section 3.4 Dry Coil
Cooling Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance \1\ tolerance \1\
------------------------------------------------------------------------
Indoor dry-bulb, [deg]F:
Entering temperature................ 2.0 0.5
Leaving temperature................. 2.0
Indoor wet-bulb, [deg]F:
[[Page 58232]]
Entering temperature................ 1.0 \2\ 0.3
Leaving temperature................. \2\ 1.0
Outdoor dry-bulb, [deg]F:
Entering temperature................ 2.0 0.5
Leaving temperature................. \3\ 2.0
Outdoor wet-bulb, [deg]F:
Entering temperature................ 1.0 \4\ 0.3
Leaving temperature................. \3\ 1.0
External resistance to airflow, inches 0.05 \5\ 0.02
of water...............................
Electrical voltage, % of rdg............ 2.0 1.5
Nozzle pressure drop, % of rdg.......... 2.0
------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Only applies during wet coil tests; does not apply during steady-
state, dry coil cooling mode tests.
\3\ Only applies when using the outdoor air enthalpy method.
\4\ Only applies during wet coil cooling mode tests where the unit
rejects condensate to the outdoor coil.
\5\ Only applies when testing non-ducted units.
e. For air conditioners and heat pumps having a constant-air-
volume-rate indoor blower, the five additional steps listed below
are required if the average of the measured external static
pressures exceeds the applicable sections 3.1.4 minimum (or target)
external static pressure ([Delta]Pmin) by 0.03 inches of
water or more.
(1) Measure the average power consumption of the indoor blower
motor (Efan,1) and record the corresponding external
static pressure ([Delta]P1) during or immediately
following the 30-minute interval used for determining capacity.
(2) After completing the 30-minute interval and while
maintaining the same test conditions, adjust the exhaust fan of the
airflow measuring apparatus until the external static pressure
increases to approximately [Delta]P1 +
([Delta]P1 - [Delta]Pmin).
(3) After re-establishing steady readings of the fan motor power
and external static pressure, determine average values for the
indoor blower power (Efan,2) and the external static
pressure ([Delta]P2) by making measurements over a 5-
minute interval.
(4) Approximate the average power consumption of the indoor
blower motor at [Delta]Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP24AU16.021
(5) Increase the total space cooling capacity,
Qc\k\(T), by the quantity (Efan,1 -
Efan,min), when expressed on a Btu/h basis. Decrease the
total electrical power, Ec\k\(T), by the same fan power
difference, now expressed in watts.
3.4 Test Procedures for the Steady-State Dry-Coil Cooling-Mode Tests
(the C, C1, C2, and G1 Tests)
a. Except for the modifications noted in this section, conduct
the steady-state dry coil cooling mode tests as specified in section
3.3 of this appendix for wet coil tests. Prior to recording data
during the steady-state dry coil test, operate the unit at least one
hour after achieving dry coil conditions. Drain the drain pan and
plug the drain opening. Thereafter, the drain pan should remain
completely dry.
b. Denote the resulting total space cooling capacity and
electrical power derived from the test as Qss,dry and
Ess,dry. With regard to a section 3.3 deviation, do not
adjust Qss,dry for duct losses (i.e., do not apply
section 7.3.3.3 of ANSI/ASHRAE 37-2009). In preparing for the
section 3.5 cyclic tests of this appendix, record the average
indoor-side air volume rate, Vi, specific heat of the air, Cp,a
(expressed on dry air basis), specific volume of the air at the
nozzles, v'n, humidity ratio at the nozzles,
Wn, and either pressure difference or velocity pressure
for the flow nozzles. For units having a variable-speed indoor
blower (that provides either a constant or variable air volume rate)
that will or may be tested during the cyclic dry coil cooling mode
test with the indoor blower turned off (see section 3.5 of this
appendix), include the electrical power used by the indoor blower
motor among the recorded parameters from the 30-minute test.
c. If the temperature sensors used to provide the primary
measurement of the indoor-side dry bulb temperature difference
during the steady-state dry-coil test and the subsequent cyclic dry-
coil test are different, include measurements of the latter sensors
among the regularly sampled data. Beginning at the start of the 30-
minute data collection period, measure and compute the indoor-side
air dry-bulb temperature difference using both sets of
instrumentation, [Delta]T (Set SS) and [Delta]T (Set CYC), for each
equally spaced data sample. If using a consistent data sampling rate
that is less than 1 minute, calculate and record minutely averages
for the two temperature differences. If using a consistent sampling
rate of one minute or more, calculate and record the two temperature
differences from each data sample. After having recorded the seventh
(i=7) set of temperature differences, calculate the following ratio
using the first seven sets of values:
[GRAPHIC] [TIFF OMITTED] TP24AU16.022
Each time a subsequent set of temperature differences is recorded
(if sampling more frequently than every 5 minutes), calculate
FCD using the most recent seven sets of values. Continue
these calculations until the 30-minute period is completed or until
a value for FCD is calculated that falls outside the
allowable range of 0.94-1.06. If the latter occurs, immediately
suspend the test and identify the cause for the disparity in the two
temperature difference measurements. Recalibration of one or both
sets of instrumentation may be required. If all the values for
FCD are within the allowable range, save the final value
of the ratio from the 30-minute test as FCD*. If the
temperature sensors used to provide the primary measurement of the
indoor-side dry bulb temperature difference during the steady-state
dry- coil test and the subsequent cyclic dry-coil test are the same,
set FCD*= 1.
3.5 Test Procedures for the Cyclic Dry-Coil Cooling-Mode Tests (the D,
D1, D2, and I1 Tests)
After completing the steady-state dry-coil test, remove the
outdoor air enthalpy method test apparatus, if connected, and begin
manual OFF/ON cycling of the unit's compressor. The test set-up
should otherwise
[[Page 58233]]
be identical to the set-up used during the steady-state dry coil
test. When testing heat pumps, leave the reversing valve during the
compressor OFF cycles in the same position as used for the
compressor ON cycles, unless automatically changed by the controls
of the unit. For units having a variable-speed indoor blower, the
manufacturer has the option of electing at the outset whether to
conduct the cyclic test with the indoor blower enabled or disabled.
Always revert to testing with the indoor blower disabled if cyclic
testing with the fan enabled is unsuccessful.
a. For all cyclic tests, the measured capacity must be adjusted
for the thermal mass stored in devices and connections located
between measured points. Follow the procedure outlined in section
7.4.3.4.5 of ASHRAE 116-2010 (incorporated by reference, see Sec.
430.3) to ensure any required measurements are taken.
b. For units having a single-speed or two-capacity compressor,
cycle the compressor OFF for 24 minutes and then ON for 6 minutes
([Delta][tau]cyc,dry = 0.5 hours). For units having a
variable-speed compressor, cycle the compressor OFF for 48 minutes
and then ON for 12 minutes ([Delta][tau]cyc,dry = 1.0
hours). Repeat the OFF/ON compressor cycling pattern until the test
is completed. Allow the controls of the unit to regulate cycling of
the outdoor fan. If an upturned duct is used, measure the dry-bulb
temperature at the inlet of the device at least once every minute
and ensure that its test operating tolerance is within
1.0[emsp14][deg]F for each compressor OFF period.
c. Sections 3.5.1 and 3.5.2 of this appendix specify airflow
requirements through the indoor coil of ducted and non-ducted indoor
units, respectively. In all cases, use the exhaust fan of the
airflow measuring apparatus (covered under section 2.6 of this
appendix) along with the indoor blower of the unit, if installed and
operating, to approximate a step response in the indoor coil
airflow. Regulate the exhaust fan to quickly obtain and then
maintain the flow nozzle static pressure difference or velocity
pressure at the same value as was measured during the steady-state
dry coil test. The pressure difference or velocity pressure should
be within 2 percent of the value from the steady-state dry coil test
within 15 seconds after airflow initiation. For units having a
variable-speed indoor blower that ramps when cycling on and/or off,
use the exhaust fan of the airflow measuring apparatus to impose a
step response that begins at the initiation of ramp up and ends at
the termination of ramp down.
d. For units having a variable-speed indoor blower, conduct the
cyclic dry coil test using the pull-thru approach described below if
any of the following occur when testing with the fan operating:
(1) The test unit automatically cycles off;
(2) Its blower motor reverses; or
(3) The unit operates for more than 30 seconds at an external
static pressure that is 0.1 inches of water or more higher than the
value measured during the prior steady-state test.
For the pull-thru approach, disable the indoor blower and use
the exhaust fan of the airflow measuring apparatus to generate the
specified flow nozzles static pressure difference or velocity
pressure. If the exhaust fan cannot deliver the required pressure
difference because of resistance created by the unpowered indoor
blower, temporarily remove the indoor blower.
e. Conduct three complete compressor OFF/ON cycles with the test
tolerances given in Table 9 satisfied. Calculate the degradation
coefficient CD for each complete cycle. If all three
CD values are within 0.02 of the average CD
then stability has been achieved, use the highest CD
value of these three. If stability has not been achieved, conduct
additional cycles, up to a maximum of eight cycles total, until
stability has been achieved between three consecutive cycles. Once
stability has been achieved, use the highest CD value of
the three consecutive cycles that establish stability. If stability
has not been achieved after eight cycles, use the highest
CD from cycle one through cycle eight, or the default
CD, whichever is lower.
f. With regard to the Table 9 parameters, continuously record
the dry-bulb temperature of the air entering the indoor and outdoor
coils during periods when air flows through the respective coils.
Sample the water vapor content of the indoor coil inlet air at least
every 2 minutes during periods when air flows through the coil.
Record external static pressure and the air volume rate indicator
(either nozzle pressure difference or velocity pressure) at least
every minute during the interval that air flows through the indoor
coil. (These regular measurements of the airflow rate indicator are
in addition to the required measurement at 15 seconds after flow
initiation.) Sample the electrical voltage at least every 2 minutes
beginning 30 seconds after compressor start-up. Continue until the
compressor, the outdoor fan, and the indoor blower (if it is
installed and operating) cycle off.
g. For ducted units, continuously record the dry-bulb
temperature of the air entering (as noted above) and leaving the
indoor coil. Or if using a thermopile, continuously record the
difference between these two temperatures during the interval that
air flows through the indoor coil. For non-ducted units, make the
same dry-bulb temperature measurements beginning when the compressor
cycles on and ending when indoor coil airflow ceases.
h. Integrate the electrical power over complete cycles of length
[Delta][tau]cyc,dry. For ducted blower coil systems
tested with the unit's indoor blower operating for the cycling test,
integrate electrical power from indoor blower OFF to indoor blower
OFF. For all other ducted units and for non-ducted units, integrate
electrical power from compressor OFF to compressor OFF. (Some cyclic
tests will use the same data collection intervals to determine the
electrical energy and the total space cooling. For other units,
terminate data collection used to determine the electrical energy
before terminating data collection used to determine total space
cooling.)
Table 9--Test Operating and Test Condition Tolerances for Cyclic Dry
Coil Cooling Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance \1\ tolerance \1\
------------------------------------------------------------------------
Indoor entering dry-bulb temperature,\2\ 2.0 0.5
[deg]F.................................
Indoor entering wet-bulb temperature, .............. (\3\)
[deg]F.................................
Outdoor entering dry-bulb 2.0 0.5
temperature,\2\ [deg]F.................
External resistance to airflow,\2\ 0.05 ..............
inches of water........................
Airflow nozzle pressure difference or 2.0 \4\ 2.0
velocity pressure,\2\ % of reading.....
Electrical voltage,\5\ % of rdg......... 2.0 1.5
------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Applies during the interval that air flows through the indoor
(outdoor) coil except for the first 30 seconds after flow initiation.
For units having a variable-speed indoor blower that ramps, the
tolerances listed for the external resistance to airflow apply from 30
seconds after achieving full speed until ramp down begins.
\3\ Shall at no time exceed a wet-bulb temperature that results in
condensate forming on the indoor coil.
\4\ The test condition must be the average nozzle pressure difference or
velocity pressure measured during the steady-state dry coil test.
\5\ Applies during the interval when at least one of the following--the
compressor, the outdoor fan, or, if applicable, the indoor blower--are
operating except for the first 30 seconds after compressor start-up.
If the Table 9 tolerances are satisfied over the complete cycle,
record the measured electrical energy consumption as
ecyc,dry and express it in units of watt-hours. Calculate
the total space cooling delivered, qcyc,dry, in units of
Btu using,
[[Page 58234]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.023
Where,
Vi,Cp,a, Vn' (or vn),
Wn, and FCD* are the values recorded during
the section 3.4 dry coil steady-state test and
Tal([tau]) = dry bulb temperature of the air entering the
indoor coil at time [tau], [deg]F.
Ta2([tau]) = dry bulb temperature of the air leaving the
indoor coil at time [tau], [deg]F.
[tau]1 = for ducted units, the elapsed time when airflow
is initiated through the indoor coil; for non-ducted units, the
elapsed time when the compressor is cycled on, hr.
[tau]2 = the elapsed time when indoor coil airflow
ceases, hr.
Adjust the total space cooling delivered, qcyc,dry,
according to calculation method outlined in section 7.4.3.4.5 of
ASHRAE 116-2010 (incorporated by reference, see Sec. 430.3).
3.5.1 Procedures When Testing Ducted Systems
The automatic controls that are normally installed with the test
unit must govern the OFF/ON cycling of the air moving equipment on
the indoor side (exhaust fan of the airflow measuring apparatus and
the indoor blower of the test unit). For ducted coil-only systems
rated based on using a fan time-delay relay, control the indoor coil
airflow according to the OFF delay listed by the manufacturer in the
certification report. For ducted units having a variable-speed
indoor blower that has been disabled (and possibly removed), start
and stop the indoor airflow at the same instances as if the fan were
enabled. For all other ducted coil-only systems, cycle the indoor
coil airflow in unison with the cycling of the compressor. If air
damper boxes are used, close them on the inlet and outlet side
during the OFF period. Airflow through the indoor coil should stop
within 3 seconds after the automatic controls of the test unit (act
to) de-energize the indoor blower. For mobile home ducted coil-only
systems increase ecyc,dry by the quantity,
[GRAPHIC] [TIFF OMITTED] TP24AU16.024
a. The product of [[tau]2 - [tau] 1] and
the indoor blower power measured during or following the dry coil
steady-state test; or,
b. The following algorithm if the indoor blower ramps its speed
when cycling.
(1) Measure the electrical power consumed by the variable-speed
indoor blower at a minimum of three operating conditions: at the
speed/air volume rate/external static pressure that was measured
during the steady-state test, at operating conditions associated
with the midpoint of the ramp-up interval, and at conditions
associated with the midpoint of the ramp-down interval. For these
measurements, the tolerances on the airflow volume or the external
static pressure are the same as required for the section 3.4 steady-
state test.
(2) For each case, determine the fan power from measurements
made over a minimum of 5 minutes.
(3) Approximate the electrical energy consumption of the indoor
blower if it had operated during the cyclic test using all three
power measurements. Assume a linear profile during the ramp
intervals. The manufacturer must provide the durations of the ramp-
up and ramp-down intervals. If the test setup instructions included
with the unit by the manufacturer specifies a ramp interval that
exceeds 45 seconds, use a 45-second ramp interval nonetheless when
estimating the fan energy.
[[Page 58235]]
3.5.2 Procedures When Testing Non-Ducted Indoor Units
Do not use airflow prevention devices when conducting cyclic
tests on non-ducted indoor units. Until the last OFF/ON compressor
cycle, airflow through the indoor coil must cycle off and on in
unison with the compressor. For the last OFF/ON compressor cycle--
the one used to determine ecyc,dry and
qcyc,dry--use the exhaust fan of the airflow measuring
apparatus and the indoor blower of the test unit to have indoor
airflow start 3 minutes prior to compressor cut-on and end three
minutes after compressor cutoff. Subtract the electrical energy used
by the indoor blower during the 3 minutes prior to compressor cut-on
from the integrated electrical energy, ecyc,dry. Add the
electrical energy used by the indoor blower during the 3 minutes
after compressor cutoff to the integrated cooling capacity,
qcyc,dry. For the case where the non-ducted indoor unit
uses a variable-speed indoor blower which is disabled during the
cyclic test, correct ecyc,dry and qcyc,dry
using the same approach as prescribed in section 3.5.1 of this
appendix for ducted units having a disabled variable-speed indoor
blower.
3.5.3 Cooling-Mode Cyclic-Degradation Coefficient Calculation
Use the two dry-coil tests to determine the cooling-mode cyclic-
degradation coefficient, CD\c\. Append ``(k=2)'' to the
coefficient if it corresponds to a two-capacity unit cycling at high
capacity. If the two optional tests are conducted but yield a tested
CD\c\ that exceeds the default CD\c\ or if the
two optional tests are not conducted, assign CD\c\ the
default value of 0.25 for variable-speed compressor systems and
outdoor units with no match, and 0.2 for all other systems. The
default value for two-capacity units cycling at high capacity,
however, is the low-capacity coefficient, i.e.,
CD\c\(k=2) = CD\c\. Evaluate CD\c\
using the above results and those from the section 3.4 dry-coil
steady-state test.
[GRAPHIC] [TIFF OMITTED] TP24AU16.025
3.6 Heating Mode Tests for Different Types of Heat Pumps, Including
Heating-Only Heat Pumps
3.6.1 Tests for a Heat Pump Having a Single-Speed Compressor and Fixed
Heating Air Volume Rate
This set of tests is for single-speed-compressor heat pumps that
do not have a heating minimum air volume rate or a heating
intermediate air volume rate that is different than the heating full
load air volume rate. Conduct the optional high temperature cyclic
(H1C) test to determine the heating mode cyclic-degradation
coefficient, CD\h\. If this optional test is conducted
but yields a tested CD\h\ that exceeds the default
CD\h\ or if the optional test is not conducted, assign
CD\h\ the default value of 0.25. Test conditions for the
four tests are specified in Table 10 of this section.
Table 10--Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor
Blower, a Constant Air Volume Rate Indoor Blower, or No Indoor Blower
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Heating air
Test description ---------------------------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H1 Test (required, steady)..... 70 60 \(max)\ 47 43 Heating Full-
load.\1\
[[Page 58236]]
H1C Test (optional, cyclic).... 70 60 \(max)\ 47 43 (\2\).
H2 Test (required)............. 70 60 \(max)\ 35 33 Heating Full-
load.\1\
H3 Test (required, steady)..... 70 60 \(max)\ 17 15 Heating Full-
load.\1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the H1 Test.
3.6.2 Tests for a Heat Pump Having a Single-Speed Compressor and a
Single Indoor Unit Having Either (1) a Variable Speed, Variable-Air-
Rate Indoor Blower Whose Capacity Modulation Correlates With Outdoor
Dry Bulb Temperature or (2) Multiple Indoor Blowers.
Conduct five tests: Two high temperature tests (H12
and H11), one frost accumulation test (H22),
and two low temperature tests (H32 and H31).
Conducting an additional frost accumulation test (H21) is
optional. Conduct the optional high temperature cyclic
(H1C1) test to determine the heating mode cyclic-
degradation coefficient, CD\h\. If this optional test is
conducted but yields a tested CD\h\ that exceeds the
default CD\h\ or if the optional test is not conducted,
assign CD\h\ the default value of 0.25. Test conditions
for the seven tests are specified in Table 11. If the optional
H21 test is not performed, use the following equations to
approximate the capacity and electrical power of the heat pump at
the H21 test conditions:
Eh\k=1\(35) = PRh\k=2\(35) * {time} Eh\k=1\(17) + 0.6 * [Eh\k=1\(47)
- Eh\k=1\(17)]{time}
Where,
[GRAPHIC] [TIFF OMITTED] TP24AU16.026
The quantities Qh\k=2\(47), Eh\k=2\(47),
Qh\k=1\(47), and Eh\k=1\(47) are determined
from the H12 and H11 tests and evaluated as
specified in section 3.7 of this appendix; the quantities
Qh\k=2\(35) and Eh\k=2\(35) are determined
from the H22 test and evaluated as specified in section
3.9 of this appendix; and the quantities Qh\k=2\(17),
Eh\k=2\(17), Qh\k=1\(17), and
Eh\k=1\(17), are determined from the H32 and
H31 tests and evaluated as specified in section 3.10 of
this appendix.
Table 11--Heating Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.6.2 Indoor Unit Requirements
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description -------------------------------------------------------------------- Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H12 Test (required, steady)..................... 70 60\(max)\ 47 43 Heating Full-load.\1\
H11 Test (required, steady)..................... 70 60\(max)\ 47 43 Heating Minimum.\2\
H1C1 Test (optional, cyclic).................... 70 60\(max)\ 47 43 (\3\).
H22 Test (required)............................. 70 60\(max)\ 35 33 Heating Full-load.\1\
H21 Test (optional)............................. 70 60\(max)\ 35 33 Heating Minimum.\2\
H32 Test (required, steady)..................... 70 60\(max)\ 17 15 Heating Full-load.\1\
H31 Test (required, steady)..................... 70 60\(max)\ 17 15 Heating Minimum.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Defined in section 3.1.4.5 of this appendix.
\3\ Maintain the airflow nozzles static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the H11 test.
[[Page 58237]]
3.6.3 Tests for a Heat Pump Having a Two-Capacity Compressor (See
Section 1.2 of This Appendix, Definitions), Including Two-Capacity,
Northern Heat Pumps (See Section 1.2 of This Appendix, Definitions)
a. Conduct one maximum temperature test (H01), two
high temperature tests (H12 and H11), one
frost accumulation test (H22), and one low temperature
test (H32). Conduct an additional frost accumulation test
(H21) and low temperature test (H31) if both
of the following conditions exist:
(1) Knowledge of the heat pump's capacity and electrical power
at low compressor capacity for outdoor temperatures of
37[emsp14][deg]F and less is needed to complete the section 4.2.3 of
this appendix seasonal performance calculations; and
(2) The heat pump's controls allow low-capacity operation at
outdoor temperatures of 37[emsp14][deg]F and less.
If the two conditions in a.(1) and a.(2) of this section are
met, an alternative to conducting the H21 frost
accumulation is to use the following equations to approximate the
capacity and electrical power:
Qh\k=1\(35) = 0.90 * {Qh\k=1\(17) + 0.6 * [Qh\k=1\(47) -
Qh\k=1\(17)]{time}
Eh\k=1\(35) = 0.985 * {Eh\k=1\(17) + 0.6 * [Eh\k=1\(47) -
Eh\k=1\(17)]{time}
Determine the quantities Qh\k=1\ (47) and
Eh\k=1\ (47) from the H11 test and evaluate
them according to section 3.7 of this appendix. Determine the
quantities Qh\k=1\ (17) and Eh\k=1\ (17) from
the H31 test and evaluate them according to section 3.10
of this appendix.
b. Conduct the optional high temperature cyclic test
(H1C1) to determine the heating mode cyclic-degradation
coefficient, CD\h\. If this optional test is conducted
but yields a tested CD\h\ that exceeds the default
CD\h\ or if the optional test is not conducted, assign
CD\h\ the default value of 0.25. If a two-capacity heat
pump locks out low capacity operation at lower outdoor temperatures,
conduct the high temperature cyclic test (H1C2) to
determine the high-capacity heating mode cyclic-degradation
coefficient, CD\h\ (k=2). If this optional test at high
capacity is conducted but yields a tested CD\h\ (k = 2)
that exceeds the default CD\h\ (k = 2) or if the optional
test is not conducted, assign CD\h\ the default value.
The default CD\h\ (k=2) is the same value as determined
or assigned for the low-capacity cyclic-degradation coefficient,
CD\h\ [or equivalently, CD\h\ (k=1)]. Table 12
specifies test conditions for these nine tests.
Table 12--Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor capacity Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady).......... 70 60\(max)\ 62 56.5 Low..................... Heating Minimum.\1\
H12 Test (required, steady).......... 70 60\(max)\ 47 43 High.................... Heating Full-Load.\2\
H1C2 Test (optional,\7\ cyclic)...... 70 60\(max)\ 47 43 High.................... (\3\).
H11 Test (required).................. 70 60\(max)\ 47 43 Low..................... Heating Minimum.\1\
H1C1 Test (optional, cyclic)......... 70 60\(max)\ 47 43 Low..................... (\4\).
H22 Test (required).................. 70 60\(max)\ 35 33 High.................... Heating Full-Load.\2\
H21 Test 5 6 (required).............. 70 60\(max)\ 35 33 Low..................... Heating Minimum.\1\
H32 Test (required, steady).......... 70 60\(max)\ 17 15 High.................... Heating Full-Load.\2\
H31 Test \5\ (required, steady)...... 70 60\(max)\ 17 15 Low..................... Heating Minimum.\1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37[emsp14][deg]F is needed
to complete the section 4.2.3 HSPF calculations.
\6\ If table note #5 applies, the section 3.6.3 equations for Qh\k=1\(35) and Eh\k=1\(17) may be used in lieu of conducting the H21 test.
\7\ Required only if the heat pump locks out low capacity operation at lower outdoor temperatures.
3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor
a. Conduct one maximum temperature test (H01), two
high temperature tests (H1N and H11), one
frost accumulation test (H2V), and one low temperature
test (H32). Conducting one or more of the following tests
is optional: An additional high temperature test (H12),
an additional frost accumulation test (H22), and a very
low temperature test (H42). Conduct the optional high
temperature cyclic (H1C1) test to determine the heating
mode cyclic-degradation coefficient, CD\h\. If this
optional test is conducted but yields a tested CD\h\ that
exceeds the default CD\h\ or if the optional test is not
conducted, assign CD\h\ the default value of 0.25. Test
conditions for the nine tests are specified in Table 13. The
compressor shall operate at the same heating full speed, measured by
RPM or power input frequency (Hz), as the maximum speed at which the
system controls would operate the compressor in normal operation in
17[emsp14][deg]F ambient temperature, for the H12,
H22 and H32 Tests. The compressor shall
operate for the H1N test at the maximum speed at which
the system controls would operate the compressor in normal operation
in 47[emsp14][deg]F ambient temperature. The compressor shall
operate at the same heating minimum speed, measured by RPM or power
input frequency (Hz), for the H01, H1C1, and
H11 Tests. Determine the heating intermediate compressor
speed cited in Table 13 using the heating mode full and minimum
compressors speeds and:
Heating intermediate speed
[GRAPHIC] [TIFF OMITTED] TP24AU16.027
[[Page 58238]]
Where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
b. If one of the high temperature tests (H12 or
H1N) is conducted using the same compressor speed (RPM or
power input frequency) as the H32 test, set the
47[emsp14][deg]F capacity and power input values used for
calculation of HSPF equal to the measured values for that test:
Qhcalc\k=2\(47) = Qh\k=2\(47); Ehcalc\k=2\(47) = Eh\k=2\(47)
Where:
Qhcalc\k=2\(47) and Ehcalc\k=2\(47) are the capacity and power input
representing full-speed operation at 47[emsp14][deg]F for the HSPF
calculations,
Qh\k=2\(47) is the capacity measured in the high temperature test
(H12 or H1N) which used the same compressor
speed as the H32 test, and
Eh\k=2\(47) is the power input measured in the high temperature test
(H12 or H1N) which used the same compressor
speed as the H32 test.
Evaluate the quantities Qh\k=2\(47) and from
Eh\k=2\(47) according to section 3.7.
Otherwise (if no high temperature test is conducted using the
same speed (RPM or power input frequency) as the H32
test), calculate the 47 [deg]F capacity and power input values used
for calculation of HSPF as follows:
Qk=2hcalc[hairsp](47) =
Qk=2h[hairsp](17) * (1 + 30 [deg]F * CSF);
Ek=2hcalc[hairsp](47) =
Ek=2h[hairsp](17) * (1 + 30 [deg]F * PSF)
Where:
Qk=2hcalc[hairsp](47) and
Ek=2hcalc[hairsp](47) are the capacity and
power input representing full-speed operation at 47 [deg]F for the
HSPF calculations,
Qk=2h[hairsp](17) is the capacity measured in
the H32 test,
Ek=2h[hairsp](17) is the power input measured
in the H32 test,
CSF is the capacity slope factor, equal to 0.0204/[deg]F for split
systems and 0.0262/[deg]F for single-package systems, and
PSF is the Power Slope Factor, equal to 0.00455/[deg]F.
c. If the H22 test is not done, use the following
equations to approximate the capacity and electrical power at the
H22 test conditions:
Qk=2h[hairsp](35) = 0.90 *
{Qk=2h[hairsp](17) + 0.6 *
[Qk=2hcalc[hairsp](47)-
Qk=2h[hairsp](17)]{time}
Ek=2h[hairsp](35) = 0.985 *
{Ek=2h[hairsp](17) + 0.6 *
[Ek=2hcalc[hairsp](47)-
Ek=2h[hairsp](17)]{time}
Where:
Qk=2hcalc[hairsp](47) and
Ek=2hcalc[hairsp](47) are the capacity and
power input representing full-speed operation at 47 [deg]F for the
HSPF calculations, calculated as described in section b above.
Qk=2h[hairsp](17) and
Ek=2h[hairsp](17) are the capacity and power
input measured in the H32 test.
d. Determine the quantities Qh\k=2\[hairsp](17) and
Eh\k=2\[hairsp](17) from the H32 test,
determine the quantities Qh\k=2\[hairsp](5) and
Eh\k=2\[hairsp](5) from the H42 test, and
evaluate all four according to section 3.10.
Table 13--Heating Mode Test Conditions for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor speed Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test............................. 70 60 \(max)\ 62 56.5 Heating Minimum......... Heating Minimum.\1\
(required, steady)...................
H12 test............................. 70 60\(max)\ 47 43 Heating Full \4\........ Heating Full-Load.\3\
(optional, steady)...................
H11 test............................. 70 60 \(max)\ 47 43 Heating Minimum......... Heating Minimum.\1\
(required, steady)...................
H1N test............................. 70 60 \(max)\ 47 43 Heating Full \5\........ Heating Full-Load.\3\
(required, steady)...................
H1C1 test............................ 70 60 \(max)\ 47 43 Heating Minimum......... (\2\)
(optional, cyclic)...................
H22 test............................. 70 60 \(max)\ 35 33 Heating Full \4\........ Heating Full-Load.\3\
(optional)...........................
H2V test............................. 70 60 \(max)\ 35 33 Heating Intermediate.... Heating
(required)........................... Intermediate.\6\
H32 test............................. 70 60 \(max)\ 17 15 Heating Full \4\........ Heating Full-Load.\3\
(required, steady)...................
H42 test............................. 70 60 \(max)\ 5 3.5 Heating Full............ Heating Full-Load.\3\
(optional, steady)...................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17 [deg]F ambient temperature. The H12 test is not needed
if the H1N test uses this same compressor speed.
\5\ Maximum speed that the system controls would operate the compressor in normal operation in 47 [deg]F ambient temperature.
\6\ Defined in section 3.1.4.6 of this appendix.
e. For multiple-split heat pumps (only), the following
procedures supersede the above requirements. For all Table 13 tests
specified for a minimum compressor speed, turn off at least one
indoor unit. The manufacturer shall designate the particular indoor
unit(s) that is turned off. The manufacturer must also specify the
compressor speed used for the Table 13 H2V test, a
heating mode intermediate compressor speed that falls within \1/4\
and \3/4\ of the difference between the full and minimum heating
mode speeds. The manufacturer should prescribe an intermediate speed
that is expected to yield the highest COP for the given
H2V test conditions and bracketed compressor speed range.
The manufacturer can designate that one or more specific indoor
units are turned off for the H2V test.
3.6.5 Additional Test for a Heat Pump Having a Heat Comfort Controller
Test any heat pump that has a heat comfort controller (see
section 1.2 of this appendix, Definitions) according to section
3.6.1, 3.6.2, or 3.6.3, whichever applies, with the heat comfort
controller disabled. Additionally, conduct the abbreviated test
described in section 3.1.9 of this appendix with the heat comfort
controller active to determine the system's maximum supply air
temperature. (Note: heat pumps having a variable speed compressor
and a heat comfort controller are not covered in the test procedure
at this time.)
3.6.6 Heating Mode Tests for Northern Heat Pumps With Triple-Capacity
Compressors
Test triple-capacity, northern heat pumps for the heating mode
as follows:
a. Conduct one maximum-temperature test (H01), two
high-temperature tests (H12 and H11), one
frost accumulation test (H22), two low-temperature tests
(H32, H33), and one minimum-temperature test
(H43). Conduct an additional frost accumulation test
(H21) and low-temperature test (H31) if both
of the following conditions exist: (1) Knowledge of
[[Page 58239]]
the heat pump's capacity and electrical power at low compressor
capacity for outdoor temperatures of 37 [deg]F and less is needed to
complete the section 4.2.6 seasonal performance calculations; and
(2) the heat pump's controls allow low-capacity operation at outdoor
temperatures of 37 [deg]F and less. If the above two conditions are
met, an alternative to conducting the H21 frost
accumulation test to determine Qh\k=1\[hairsp](35) and
Eh\k=1\[hairsp](35) is to use the following equations to
approximate this capacity and electrical power:
Qk=1h[hairsp](35) = 0.90 *
{Qk=1h[hairsp](17) + 0.6 *
[Qk=1h[hairsp](47)-
Qk=1h[hairsp](17)]{time}
Ek=1h[hairsp](35) = 0.985 *
{Ek=1h[hairsp](17) + 0.6 *
[Ek=1h[hairsp](47)-
Ek=1h[hairsp](17)]{time}
In evaluating the above equations, determine the quantities
Qh\k=1\[hairsp](47) from the H11 test and
evaluate them according to section 3.7 of this appendix. Determine
the quantities Qh\k=1\[hairsp](17) and
Eh\k=1\[hairsp](17) from the H31 test and
evaluate them according to section 3.10 of this appendix. Use the
paired values of Qh\k=1\[hairsp](35) and
Eh\k=1\[hairsp](35) derived from conducting the
H21 frost accumulation test and evaluated as specified in
section 3.9.1 of this appendix or use the paired values calculated
using the above default equations, whichever contribute to a higher
Region IV HSPF based on the DHRmin.
b. Conducting a frost accumulation test (H23) with
the heat pump operating at its booster capacity is optional. If this
optional test is not conducted, determine
Qh\k=3\[hairsp](35) and Eh\k=3\[hairsp](35)
using the following equations to approximate this capacity and
electrical power:
Qh\k=3\(35) = QRh\k=2\(35) * {Qh\k=3\(17) + 1.20 * [Qh\k=3\(17)-
Qh\k=3\(2)]{time}
Eh\k=3\(35) = PRh\k=2\(35) * {Eh\k=3\(17) + 1.20 * [Eh\k=3\(17)-
Eh\k=3\(2)]{time}
Where:
[GRAPHIC] [TIFF OMITTED] TP24AU16.028
Determine the quantities Qh\k=2\(47) and
Eh\k=2\(47) from the H12 test and evaluate
them according to section 3.7 of this appendix. Determine the
quantities Qh\k=2\(35) and Eh\k=2\(35) from
the H22 test and evaluate them according to section 3.9.1
of this appendix. Determine the quantities Qh\k=2\(17)
and Eh\k=2\(17) from the H32 test, determine
the quantities Qh\k=3\(17) and Eh\k=3\(17)
from the H33 test, and determine the quantities
Qh\k=3\(2) and Eh\k=3\(2) from the
H43 test. Evaluate all six quantities according to
section 3.10 of this appendix. Use the paired values of
Qh\k=3\(35) and Eh\k=3\(35) derived from
conducting the H23 frost accumulation test and calculated
as specified in section 3.9.1 of this appendix or use the paired
values calculated using the above default equations, whichever
contribute to a higher Region IV HSPF based on the DHRmin.
c. Conduct the optional high-temperature cyclic test
(H1C1) to determine the heating mode cyclic-degradation
coefficient, CD\h\. A default value for CD\h\
of 0.25 may be used in lieu of conducting the cyclic. If a triple-
capacity heat pump locks out low capacity operation at lower outdoor
temperatures, conduct the high-temperature cyclic test
(H1C2) to determine the high-capacity heating mode
cyclic-degradation coefficient, CD\h\ (k=2). The default
CD\h\ (k=2) is the same value as determined or assigned
for the low-capacity cyclic-degradation coefficient,
CD\h\ [or equivalently, CD\h\ (k=1)]. Finally,
if a triple-capacity heat pump locks out both low and high capacity
operation at the lowest outdoor temperatures, conduct the low-
temperature cyclic test (H3C3) to determine the booster-
capacity heating mode cyclic-degradation coefficient,
CD\h\ (k=3). The default CD\h\ (k=3) is the
same value as determined or assigned for the high-capacity cyclic-
degradation coefficient, CD\h\ [or equivalently,
CD\h\ (k=2)]. Table 14 specifies test conditions for all
13 tests.
Table 14--Heating Mode Test Conditions for Units With a Triple-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature [deg]F temperature [deg]F
Test description ---------------------------------------------------------------- Compressor capacity Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady).......... 70 60 \(max)\ 62 56.5 Low..................... Heating Minimum.\1\
H12 Test (required, steady).......... 70 60 \(max)\ 47 43 High.................... Heating Full-Load.\2\
H1C2 Test (optional \8\, cyclic)..... 70 60 \(max)\ 47 43 High.................... (\3\).
H11 Test (required).................. 70 60 \(max)\ 47 43 Low..................... Heating Minimum.\1\
H1C1 Test (optional, cyclic)......... 70 60 \(max)\ 47 43 Low..................... (\4\).
H23 Test (optional, steady).......... 70 60 \(max)\ 35 33 Booster................. Heating Full-Load.\2\
H22 Test (required).................. 70 60 \(max)\ 35 33 High.................... Heating Full-Load.\2\
H21 Test (required).................. 70 60 \(max)\ 35 33 Low..................... Heating Minimum.\1\
H33 Test (required, steady).......... 70 60 \(max)\ 17 15 Booster................. Heating Full-Load.\2\
H3C3 Test 5 6 (optional, cyclic)..... 70 60 \(max)\ 17 15 Booster................. (\7\).
H32 Test (required, steady).......... 70 60 \(max)\ 17 15 High.................... Heating Full-Load.\2\
H31 Test \5\ (required, steady)...... 70 60 \(max)\ 17 15 Low..................... Heating Minimum.\1\
[[Page 58240]]
H43 Test (required, steady).......... 70 60 \(max)\ 2 1 Booster................. Heating Full-Load.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 [deg]F is needed to
complete the section 4.2.6 HSPF calculations.
\6\ If table note \5\ applies, the section 3.6.6 equations for Qh\k=1\(35) and Eh\k=1\(17) may be used in lieu of conducting the H21 test.
\7\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H33 test.
\8\ Required only if the heat pump locks out low capacity operation at lower outdoor temperatures.
3.6.7 Tests for a Heat Pump Having a Single Indoor Unit Having Multiple
Indoor Blowers and Offering Two Stages of Compressor Modulation
Conduct the heating mode tests specified in section 3.6.3 of
this appendix.
3.7 Test Procedures for Steady-State Maximum Temperature and High
Temperature Heating Mode Tests (the H01, H1, H12,
H11, and H1N Tests)
a. For the pretest interval, operate the test room
reconditioning apparatus and the heat pump until equilibrium
conditions are maintained for at least 30 minutes at the specified
section 3.6 test conditions. Use the exhaust fan of the airflow
measuring apparatus and, if installed, the indoor blower of the heat
pump to obtain and then maintain the indoor air volume rate and/or
the external static pressure specified for the particular test.
Continuously record the dry-bulb temperature of the air entering the
indoor coil, and the dry-bulb temperature and water vapor content of
the air entering the outdoor coil. Refer to section 3.11 of this
appendix for additional requirements that depend on the selected
secondary test method. After satisfying the pretest equilibrium
requirements, make the measurements specified in Table 3 of ANSI/
ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3) for the
indoor air enthalpy method and the user-selected secondary method.
Make said Table 3 measurements at equal intervals that span 5
minutes or less. Continue data sampling until a 30-minute period
(e.g., seven consecutive 5-minute samples) is reached where the test
tolerances specified in Table 15 are satisfied. For those
continuously recorded parameters, use the entire data set for the
30-minute interval when evaluating Table 15 compliance. Determine
the average electrical power consumption of the heat pump over the
same 30-minute interval.
Table 15--Test Operating and Test Condition Tolerances for Section 3.7
and Section 3.10 Steady-State Heating Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance\1\ tolerance\1\
------------------------------------------------------------------------
Indoor dry-bulb, [deg]F:................ .............. ..............
Entering temperature................ 2.0 0.5
Leaving temperature................. 2.0 ..............
Indoor wet-bulb, [deg]F:................ .............. ..............
Entering temperature................ 1.0 ..............
Leaving temperature................. 1.0 ..............
Outdoor dry-bulb, [deg]F:............... .............. ..............
Entering temperature................ 2.0 0.5
Leaving temperature................. \2\ 2.0 ..............
Outdoor wet-bulb, [deg]F:............... .............. ..............
Entering temperature................ 1.0 0.3
Leaving temperature................. \2\ 1.0 ..............
External resistance to airflow, inches 0.05 \3\ 0.02
of water...............................
Electrical voltage, % of rdg............ 2.0 1.5
Nozzle pressure drop, % of rdg.......... 2.0 ..............
------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Only applies when the Outdoor Air Enthalpy Method is used.
\3\ Only applies when testing non-ducted units.
b. Calculate indoor-side total heating capacity as specified in
sections 7.3.4.1 and 7.3.4.3 of ANSI/ASHRAE 37-2009 (incorporated by
reference, see Sec. 430.3). To calculate capacity, use the averages
of the measurements (e.g. inlet and outlet dry bulb temperatures
measured at the psychrometers) that are continuously recorded for
the same 30-minute interval used as described above to evaluate
compliance with test tolerances. Do not adjust the parameters used
in calculating capacity for the permitted variations in test
conditions. Assign the average space heating capacity and electrical
power over the 30-minute data collection interval to the variables
Qh\k\ and Eh\k\(T) respectively. The ``T'' and
superscripted ``k'' are the same as described in section 3.3 of this
appendix. Additionally, for the heating mode, use the superscript to
denote results from the optional H1N test, if conducted.
c. For mobile home coil-only system heat pumps, increase
Qh\k\(T) by
[[Page 58241]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.029
where Vis is the average measured indoor air volume rate
expressed in units of cubic feet per minute of standard air (scfm).
During the 30-minute data collection interval of a high temperature
test, pay attention to preventing a defrost cycle. Prior to this
time, allow the heat pump to perform a defrost cycle if
automatically initiated by its own controls. As in all cases, wait
for the heat pump's defrost controls to automatically terminate the
defrost cycle. Heat pumps that undergo a defrost should operate in
the heating mode for at least 10 minutes after defrost termination
prior to beginning the 30-minute data collection interval. For some
heat pumps, frost may accumulate on the outdoor coil during a high
temperature test. If the indoor coil leaving air temperature or the
difference between the leaving and entering air temperatures
decreases by more than 1.5[emsp14][deg]F over the 30-minute data
collection interval, then do not use the collected data to determine
capacity. Instead, initiate a defrost cycle. Begin collecting data
no sooner than 10 minutes after defrost termination. Collect 30
minutes of new data during which the Table 15 test tolerances are
satisfied. In this case, use only the results from the second 30-
minute data collection interval to evaluate Qh\k\(47) and
Eh\k\(47).
d. If conducting the cyclic heating mode test, which is
described in section 3.8 of this appendix, record the average
indoor-side air volume rate, Vi, specific heat of the air,
Cp,a (expressed on dry air basis), specific volume of the
air at the nozzles, vn' (or vn), humidity
ratio at the nozzles, Wn, and either pressure difference
or velocity pressure for the flow nozzles. If either or both of the
below criteria apply, determine the average, steady-state,
electrical power consumption of the indoor blower motor
(Efan,1):
(1) The section 3.8 cyclic test will be conducted and the heat
pump has a variable-speed indoor blower that is expected to be
disabled during the cyclic test; or
(2) The heat pump has a (variable-speed) constant-air volume-
rate indoor blower and during the steady-state test the average
external static pressure ([Delta]P1) exceeds the
applicable section 3.1.4.4 minimum (or targeted) external static
pressure ([Delta]Pmin) by 0.03 inches of water or more.
Determine Efan,1 by making measurements during the
30-minute data collection interval, or immediately following the
test and prior to changing the test conditions. When the above ``2''
criteria applies, conduct the following four steps after determining
Efan,1 (which corresponds to [Delta]P1):
(i) While maintaining the same test conditions, adjust the
exhaust fan of the airflow measuring apparatus until the external
static pressure increases to approximately [Delta]P1 +
([Delta]P1 - [Delta]Pmin).
(ii) After re-establishing steady readings for fan motor power
and external static pressure, determine average values for the
indoor blower power (Efan,2) and the external static
pressure ([Delta]P2) by making measurements over a 5-
minute interval.
(iii) Approximate the average power consumption of the indoor
blower motor if the 30-minute test had been conducted at
[Delta]Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP24AU16.030
(iv) Decrease the total space heating capacity,
Qh\k\(T), by the quantity (Efan,1 -
Efan,min), when expressed on a Btu/h basis. Decrease the
total electrical power, Eh\k\(T) by the same fan power
difference, now expressed in watts.
e. If the temperature sensors used to provide the primary
measurement of the indoor-side dry bulb temperature difference
during the steady-state dry-coil test and the subsequent cyclic dry-
coil test are different, include measurements of the latter sensors
among the regularly sampled data. Beginning at the start of the 30-
minute data collection period, measure and compute the indoor-side
air dry-bulb temperature difference using both sets of
instrumentation, [Delta]T (Set SS) and [Delta]T (Set CYC), for each
equally spaced data sample. If using a consistent data sampling rate
that is less than 1 minute, calculate and record minutely averages
for the two temperature differences. If using a consistent sampling
rate of one minute or more, calculate and record the two temperature
[[Page 58242]]
differences from each data sample. After having recorded the seventh
(i=7) set of temperature differences, calculate the following ratio
using the first seven sets of values:
[GRAPHIC] [TIFF OMITTED] TP24AU16.031
Each time a subsequent set of temperature differences is
recorded (if sampling more frequently than every 5 minutes),
calculate FCD using the most recent seven sets of values.
Continue these calculations until the 30-minute period is completed
or until a value for FCD is calculated that falls outside
the allowable range of 0.94-1.06. If the latter occurs, immediately
suspend the test and identify the cause for the disparity in the two
temperature difference measurements. Recalibration of one or both
sets of instrumentation may be required. If all the values for
FCD are within the allowable range, save the final value
of the ratio from the 30-minute test as FCD*. If the
temperature sensors used to provide the primary measurement of the
indoor-side dry bulb temperature difference during the steady-state
dry-coil test and the subsequent cyclic dry-coil test are the same,
set FCD*= 1.
3.8 Test Procedures for the Cyclic Heating Mode Tests (the
H0C1, H1C, H1C1 and H1C2 Tests)
a. Except as noted below, conduct the cyclic heating mode test
as specified in section 3.5 of this appendix. As adapted to the
heating mode, replace section 3.5 references to ``the steady-state
dry coil test'' with ``the heating mode steady-state test conducted
at the same test conditions as the cyclic heating mode test.'' Use
the test tolerances in Table 16 rather than Table 9. Record the
outdoor coil entering wet-bulb temperature according to the
requirements given in section 3.5 of this appendix for the outdoor
coil entering dry-bulb temperature. Drop the subscript ``dry'' used
in variables cited in section 3.5 of this appendix when referring to
quantities from the cyclic heating mode test. If available, use
electric resistance heaters (see section 2.1 of this appendix) to
minimize the variation in the inlet air temperature. Determine the
total space heating delivered during the cyclic heating test,
qcyc, as specified in section 3.5 of this appendix except
for making the following changes:
(1) When evaluating Equation 3.5-1, use the values of Vi,
Cp,a,vn', (or vn), and
Wn that were recorded during the section 3.7 steady-state
test conducted at the same test conditions.
(2) Calculate [Gamma] using,
[Gamma]=FCD*[int][tau]1[tau]2[Ta1([t
au])-Ta2([tau])][delta][tau], hr x [deg] F,
where FCD* is the value recorded during the section 3.7
steady-state test conducted at the same test condition.
b. For ducted coil-only system heat pumps (excluding the special
case where a variable-speed fan is temporarily removed), increase
qcyc by the amount calculated using Equation 3.5-3.
Additionally, increase ecyc by the amount calculated
using Equation 3.5-2. In making these calculations, use the average
indoor air volume rate (Vis) determined from the section
3.7 steady-state heating mode test conducted at the same test
conditions.
c. For non-ducted heat pumps, subtract the electrical energy
used by the indoor blower during the 3 minutes after compressor
cutoff from the non-ducted heat pump's integrated heating capacity,
qcyc.
d. If a heat pump defrost cycle is manually or automatically
initiated immediately prior to or during the OFF/ON cycling, operate
the heat pump continuously until 10 minutes after defrost
termination. After that, begin cycling the heat pump immediately or
delay until the specified test conditions have been re-established.
Pay attention to preventing defrosts after beginning the cycling
process. For heat pumps that cycle off the indoor blower during a
defrost cycle, make no effort here to restrict the air movement
through the indoor coil while the fan is off. Resume the OFF/ON
cycling while conducting a minimum of two complete compressor OFF/ON
cycles before determining qcyc and ecyc.
3.8.1 Heating Mode Cyclic-Degradation Coefficient Calculation
Use the results from the required cyclic test and the required
steady-state test that were conducted at the same test conditions to
determine the heating mode cyclic-degradation coefficient
CD\h\. Add ``(k=2)'' to the coefficient if it corresponds
to a two-capacity unit cycling at high capacity. For the below
calculation of the heating mode cyclic degradation coefficient, do
not include the duct loss correction from section 7.3.3.3 of ANSI/
ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3) in
determining Qh\k\(Tcyc) (or qcyc).
If the optional cyclic test is conducted but yields a tested
CD\h\ that exceeds the default CD\h\ or if the
optional test is not conducted, assign CD\h\ the default
value of 0.25. The default value for two-capacity units cycling at
high capacity, however, is the low-capacity coefficient, i.e.,
CD\h\ (k=2) = CD\h\. The tested
CD\h\ is calculated as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.032
the average coefficient of performance during the steady-state
heating mode test conducted at the same test conditions--i.e., same
outdoor dry bulb temperature, Tcyc, and speed/capacity,
k, if applicable--as specified for the cyclic heating mode test,
dimensionless.
[GRAPHIC] [TIFF OMITTED] TP24AU16.033
the heating load factor, dimensionless.
[[Page 58243]]
Tcyc = the nominal outdoor temperature at which the
cyclic heating mode test is conducted, 62 or 47[emsp14][deg]F.
[Delta][tau]cyc = the duration of the OFF/ON intervals;
0.5 hours when testing a heat pump having a single-speed or two-
capacity compressor and 1.0 hour when testing a heat pump having a
variable-speed compressor.
Round the calculated value for CD\h\ to the nearest
0.01. If CD\h\ is negative, then set it equal to zero.
Table 16--Test Operating and Test Condition Tolerances for Cyclic
Heating Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance\1\ tolerance\1\
------------------------------------------------------------------------
Indoor entering dry-bulb temperature,\2\ 2.0 0.5
[deg]F.................................
Indoor entering wet-bulb temperature,\2\ 1.0 ..............
[deg]F.................................
Outdoor entering dry-bulb 2.0 0.5
temperature,\2\ [deg]F.................
Outdoor entering wet-bulb 2.0 1.0
temperature,\2\ [deg]F.................
External resistance to air-flow,\2\ 0.05 ..............
inches of water........................
Airflow nozzle pressure difference or 2.0 \3\2.0
velocity pressure,\2%\ of reading......
Electrical voltage,\4%\ of rdg.......... 2.0 1.5
------------------------------------------------------------------------
\1\See section 1.2 of this appendix, Definitions.
\2\Applies during the interval that air flows through the indoor
(outdoor) coil except for the first 30 seconds after flow initiation.
For units having a variable-speed indoor blower that ramps, the
tolerances listed for the external resistance to airflow shall apply
from 30 seconds after achieving full speed until ramp down begins.
\3\The test condition must be the average nozzle pressure difference or
velocity pressure measured during the steady-state test conducted at
the same test conditions.
\4\Applies during the interval that at least one of the following--the
compressor, the outdoor fan, or, if applicable, the indoor blower--are
operating, except for the first 30 seconds after compressor start-up.
3.9 Test Procedures for Frost Accumulation Heating Mode Tests (the H2,
H22, H2V, and H21 Tests)
a. Confirm that the defrost controls of the heat pump are set as
specified in section 2.2.1 of this appendix. Operate the test room
reconditioning apparatus and the heat pump for at least 30 minutes
at the specified section 3.6 test conditions before starting the
``preliminary'' test period. The preliminary test period must
immediately precede the ``official'' test period, which is the
heating and defrost interval over which data are collected for
evaluating average space heating capacity and average electrical
power consumption.
b. For heat pumps containing defrost controls which are likely
to cause defrosts at intervals less than one hour, the preliminary
test period starts at the termination of an automatic defrost cycle
and ends at the termination of the next occurring automatic defrost
cycle. For heat pumps containing defrost controls which are likely
to cause defrosts at intervals exceeding one hour, the preliminary
test period must consist of a heating interval lasting at least one
hour followed by a defrost cycle that is either manually or
automatically initiated. In all cases, the heat pump's own controls
must govern when a defrost cycle terminates.
c. The official test period begins when the preliminary test
period ends, at defrost termination. The official test period ends
at the termination of the next occurring automatic defrost cycle.
When testing a heat pump that uses a time-adaptive defrost control
system (see section 1.2 of this appendix, Definitions), however,
manually initiate the defrost cycle that ends the official test
period at the instant indicated by instructions provided by the
manufacturer. If the heat pump has not undergone a defrost after 6
hours, immediately conclude the test and use the results from the
full 6-hour period to calculate the average space heating capacity
and average electrical power consumption.
For heat pumps that turn the indoor blower off during the
defrost cycle, take steps to cease forced airflow through the indoor
coil and block the outlet duct whenever the heat pump's controls
cycle off the indoor blower. If it is installed, use the outlet
damper box described in section 2.5.4.1 of this appendix to affect
the blocked outlet duct.
d. Defrost termination occurs when the controls of the heat pump
actuate the first change in converting from defrost operation to
normal heating operation. Defrost initiation occurs when the
controls of the heat pump first alter its normal heating operation
in order to eliminate possible accumulations of frost on the outdoor
coil.
e. To constitute a valid frost accumulation test, satisfy the
test tolerances specified in Table 17 during both the preliminary
and official test periods. As noted in Table 17, test operating
tolerances are specified for two sub-intervals: (1) When heating,
except for the first 10 minutes after the termination of a defrost
cycle (sub-interval H, as described in Table 17) and (2) when
defrosting, plus these same first 10 minutes after defrost
termination (sub-interval D, as described in Table 17). Evaluate
compliance with Table 17 test condition tolerances and the majority
of the test operating tolerances using the averages from
measurements recorded only during sub-interval H. Continuously
record the dry bulb temperature of the air entering the indoor coil,
and the dry bulb temperature and water vapor content of the air
entering the outdoor coil. Sample the remaining parameters listed in
Table 17 at equal intervals that span 5 minutes or less.
f. For the official test period, collect and use the following
data to calculate average space heating capacity and electrical
power. During heating and defrosting intervals when the controls of
the heat pump have the indoor blower on, continuously record the
dry-bulb temperature of the air entering (as noted above) and
leaving the indoor coil. If using a thermopile, continuously record
the difference between the leaving and entering dry-bulb
temperatures during the interval(s) that air flows through the
indoor coil. For coil-only system heat pumps, determine the
corresponding cumulative time (in hours) of indoor coil airflow,
[Delta][tau]a. Sample measurements used in calculating
the air volume rate (refer to sections 7.7.2.1 and 7.7.2.2 of ANSI/
ASHRAE 37-2009) at equal intervals that span 10 minutes or less.
(Note: In the first printing of ANSI/ASHRAE 37-2009, the second IP
equation for Qmi should read:) Record the electrical
energy consumed, expressed in watt-hours, from defrost termination
to defrost termination, eDEF\k\(35), as well as the
corresponding elapsed time in hours, [Delta][tau]FR.
Table 17--Test Operating and Test Condition Tolerances for Frost Accumulation Heating Mode Tests
----------------------------------------------------------------------------------------------------------------
Test operating tolerance\1\ Test condition
-------------------------------- tolerance\1\
Sub-interval Sub-interval Sub-interval
H\2\ D\3\ H\2\
----------------------------------------------------------------------------------------------------------------
Indoor entering dry-bulb temperature, [deg]F.................... 2.0 \4\ 4.0 0.5
Indoor entering wet-bulb temperature, [deg]F.................... 1.0 .............. ..............
Outdoor entering dry-bulb temperature, [deg]F................... 2.0 10.0 1.0
[[Page 58244]]
Outdoor entering wet-bulb temperature, [deg]F................... 1.5 .............. 0.5
External resistance to airflow, inches of water................. 0.05 .............. \5\ 0.02
Electrical voltage, % of rdg.................................... 2.0 .............. 1.5
----------------------------------------------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Applies when the heat pump is in the heating mode, except for the first 10 minutes after termination of a
defrost cycle.
\3\ Applies during a defrost cycle and during the first 10 minutes after the termination of a defrost cycle when
the heat pump is operating in the heating mode.
\4\ For heat pumps that turn off the indoor blower during the defrost cycle, the noted tolerance only applies
during the 10 minute interval that follows defrost termination.
\5\ Only applies when testing non-ducted heat pumps.
3.9.1 Average Space Heating Capacity and Electrical Power Calculations
a. Evaluate average space heating capacity,
Qh\k\(35), when expressed in units of Btu per hour,
using:
[GRAPHIC] [TIFF OMITTED] TP24AU16.034
Where,
Vi = the average indoor air volume rate measured during sub-interval
H, cfm.
Cp,a = 0.24 + 0.444 [middot] Wn, the constant
pressure specific heat of the air-water vapor mixture that flows
through the indoor coil and is expressed on a dry air basis, Btu/
lbmda [middot] [deg]F.
vn' = specific volume of the air-water vapor mixture at
the nozzle, ft\3\/lbmmx.
Wn = humidity ratio of the air-water vapor mixture at the
nozzle, lbm of water vapor per lbm of dry air.
[Delta][tau]FR = [tau]2 - [tau]1,
the elapsed time from defrost termination to defrost termination,
hr.
[Gamma] = [int]\[tau]2\[tau]1[Ta2([tau]) -
Ta1([tau])]d[tau], hr * [deg]F
Tal([tau]) = dry bulb temperature of the air entering the
indoor coil at elapsed time [tau], [deg]F; only recorded when indoor
coil airflow occurs; assigned the value of zero during periods (if
any) where the indoor blower cycles off.
Ta2([tau]) = dry bulb temperature of the air leaving the
indoor coil at elapsed time [tau], [deg]F; only recorded when indoor
coil airflow occurs; assigned the value of zero during periods (if
any) where the indoor blower cycles off.
[tau]1 = the elapsed time when the defrost termination
occurs that begins the official test period, hr.
[tau]2 = the elapsed time when the next automatically
occurring defrost termination occurs, thus ending the official test
period, hr.
vn = specific volume of the dry air portion of the
mixture evaluated at the dry-bulb temperature, vapor content, and
barometric pressure existing at the nozzle, ft\3\ per lbm of dry
air.
To account for the effect of duct losses between the outlet of
the indoor unit and the section 2.5.4 dry-bulb temperature grid,
adjust Qh\k\(35) in accordance with section 7.3.4.3 of
ANSI/ASHRAE 37-2009 (incorporated by reference, see Sec. 430.3).
b. Evaluate average electrical power, Eh\k\(35), when
expressed in units of watts, using:
[[Page 58245]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.035
where Vis is the average measured indoor air volume rate
expressed in units of cubic feet per minute of standard air (scfm).
c. For heat pumps having a constant-air-volume-rate indoor
blower, the five additional steps listed below are required if the
average of the external static pressures measured during sub-
interval H exceeds the applicable section 3.1.4.4, 3.1.4.5, or
3.1.4.6 minimum (or targeted) external static pressure
([Delta]Pmin) by 0.03 inches of water or more:
(1) Measure the average power consumption of the indoor blower
motor (Efan,1) and record the corresponding external
static pressure ([Delta]P1) during or immediately
following the frost accumulation heating mode test. Make the
measurement at a time when the heat pump is heating, except for the
first 10 minutes after the termination of a defrost cycle.
(2) After the frost accumulation heating mode test is completed
and while maintaining the same test conditions, adjust the exhaust
fan of the airflow measuring apparatus until the external static
pressure increases to approximately [Delta]P1 +
([Delta]P1 - [Delta]Pmin).
(3) After re-establishing steady readings for the fan motor
power and external static pressure, determine average values for the
indoor blower power (Efan,2) and the external static
pressure ([Delta]P2) by making measurements over a 5-
minute interval.
(4) Approximate the average power consumption of the indoor
blower motor had the frost accumulation heating mode test been
conducted at [Delta]Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP24AU16.036
(5) Decrease the total heating capacity, Qh\k\(35),
by the quantity [(Efan,1 - Efan,min)[middot]
([Delta][tau]a/[Delta][tau]FR], when expressed
on a Btu/h basis. Decrease the total electrical power,
Eh\k\(35), by the same quantity, now expressed in watts.
3.9.2 Demand Defrost Credit
a. Assign the demand defrost credit, Fdef, that is
used in section 4.2 of this appendix to the value of 1 in all cases
except for heat pumps having a demand-defrost control system (see
section 1.2 of this appendix, Definitions). For such qualifying heat
pumps, evaluate Fdef using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.037
[[Page 58246]]
Where:
[Delta][tau]def = the time between defrost terminations
(in hours) or 1.5, whichever is greater.
Assign a value of 6 to [Delta][tau]def if this limit is
reached during a frost accumulation test and the heat pump has not
completed a defrost cycle.
[Delta][tau]max = maximum time between defrosts as
allowed by the controls (in hours) or 12, whichever is less, as
provided in the certification report.
b. For two-capacity heat pumps and for section 3.6.2 units,
evaluate the above equation using the [Delta][tau]def
that applies based on the frost accumulation test conducted at high
capacity and/or at the heating full-load air volume rate. For
variable-speed heat pumps, evaluate [Delta][tau]def based
on the required frost accumulation test conducted at the
intermediate compressor speed.
3.10 Test Procedures for Steady-State Low Temperature and Very Low
Temperature Heating Mode Tests (the H3, H32, H31,
H33, H43, and H42 Tests)
Except for the modifications noted in this section, conduct the
low temperature and very low temperature heating mode tests using
the same approach as specified in section 3.7 of this appendix for
the maximum and high temperature tests. After satisfying the section
3.7 requirements for the pretest interval but before beginning to
collect data to determine the capacity and power input, conduct a
defrost cycle. This defrost cycle may be manually or automatically
initiated. Terminate the defrost sequence using the heat pump's
defrost controls. Begin the 30-minute data collection interval
described in section 3.7 of this appendix, from which the capacity
and power input are determined, no sooner than 10 minutes after
defrost termination. Defrosts should be prevented over the 30-minute
data collection interval.
3.11 Additional Requirements for the Secondary Test Methods
3.11.1 If Using the Outdoor Air Enthalpy Method as the Secondary Test
Method
a. For all cooling mode and heating mode tests, first conduct a
test without the outdoor air-side test apparatus described in
section 2.10.1 connected to the outdoor unit (``non-ducted'' test).
b. For the first section 3.2 steady-state cooling mode test and
the first section 3.6 steady-state heating mode test, conduct a
second test in which the outdoor-side apparatus is connected
(``ducted'' test). No other cooling mode or heating mode tests
require the ducted test so long as the unit operates the outdoor fan
during all cooling mode steady-state tests at the same speed and all
heating mode steady-state tests at the same speed. If using more
than one outdoor fan speed for the cooling mode steady-state tests,
however, conduct the ducted test for each cooling mode test where a
different fan speed is first used. This same requirement applies for
the heating mode tests.
3.11.1.3 Non-Ducted Test
a. For the non-ducted test, connect the indoor air-side test
apparatus to the indoor coil; do not connect the outdoor air-side
test apparatus. Allow the test room reconditioning apparatus and the
unit being tested to operate for at least one hour. After attaining
equilibrium conditions, measure the following quantities at equal
intervals that span 5 minutes or less:
(1) The section 2.10.1 evaporator and condenser temperatures or
pressures;
(2) Parameters required according to the Indoor Air Enthalpy
Method.
Continue these measurements until a 30-minute period (e.g.,
seven consecutive 5-minute samples) is obtained where the Table 8 or
Table 15, whichever applies, test tolerances are satisfied.
b. For cases where a ducted test is not required per section
3.11.1.b of this appendix, the non-ducted test constitutes the
``official'' test for which validity is not based on comparison with
a secondary test.
c. For cases where a ducted test is required per section
3.11.1.b of this appendix, the following conditions must be met for
the non-ducted test to constitute a valid ``official'' test:
(1) The energy balance specified in section 3.1.1 is achieved
for the ducted test (i.e., compare the capacities determined using
the indoor air enthalpy method and the outdoor air enthalpy method).
(2) The capacities determined using the indoor air enthalpy
method from the ducted and non-ducted tests must agree within 2.0
percent.
3.11.1.4 Ducted Test
a. The test conditions and tolerances for the ducted test are
the same as specified for the official test.
b. After collecting 30 minutes of steady-state data during the
non-ducted test, connect the outdoor air-side test apparatus to the
unit for the ducted test. Adjust the exhaust fan of the outdoor
airflow measuring apparatus until averages for the evaporator and
condenser temperatures, or the saturated temperatures corresponding
to the measured pressures, agree within 0.5[emsp14][deg]F of the averages achieved during the non-
ducted test. Calculate the averages for the ducted test using five
or more consecutive readings taken at one minute intervals. Make
these consecutive readings after re-establishing equilibrium
conditions.
c. During the ducted test, at one minute intervals, measure the
parameters required according to the indoor air enthalpy method and
the outdoor air enthalpy method.
d. For cooling mode ducted tests, calculate capacity based on
outdoor air-enthalpy measurements as specified in sections 7.3.3.2
and 7.3.3.3 of ANSI/ASHRAE 37-2009 (incorporated by reference, see
Sec. 430.3). For heating mode ducted tests, calculate heating
capacity based on outdoor air-enthalpy measurements as specified in
sections 7.3.4.2 and 7.3.3.4.3 of the same ANSI/ASHRAE Standard.
Adjust the outdoor-side capacity according to section 7.3.3.4 of
ANSI/ASHRAE 37-2009 to account for line losses when testing split
systems.
3.11.2 If Using the Compressor Calibration Method as the Secondary Test
Method
a. Conduct separate calibration tests using a calorimeter to
determine the refrigerant flow rate. Or for cases where the
superheat of the refrigerant leaving the evaporator is less than
5[emsp14][deg]F, use the calorimeter to measure total capacity
rather than refrigerant flow rate. Conduct these calibration tests
at the same test conditions as specified for the tests in this
appendix. Operate the unit for at least one hour or until obtaining
equilibrium conditions before collecting data that will be used in
determining the average refrigerant flow rate or total capacity.
Sample the data at equal intervals that span 5 minutes or less.
Determine average flow rate or average capacity from data sampled
over a 30-minute period where the Table 8 (cooling) or the Table 15
(heating) tolerances are satisfied. Otherwise, conduct the
calibration tests according to sections 5, 6, 7, and 8 of ASHRAE
23.1-2010 (incorporated by reference, see Sec. 430.3); sections 5,
6, 7, 8, 9, and 11 of ASHRAE 41.9-2011 (incorporated by reference,
see Sec. 430.3); and section 7.4 of ANSI/ASHRAE 37-2009
(incorporated by reference, see Sec. 430.3).
b. Calculate space cooling and space heating capacities using
the compressor calibration method measurements as specified in
section 7.4.5 and 7.4.6 respectively, of ANSI/ASHRAE 37-2009.
3.11.3 If Using the Refrigerant-Enthalpy Method as the Secondary Test
Method
Conduct this secondary method according to section 7.5 of ANSI/
ASHRAE 37-2009. Calculate space cooling and heating capacities using
the refrigerant-enthalpy method measurements as specified in
sections 7.5.4 and 7.5.5, respectively, of the same ASHRAE Standard.
3.12 Rounding of Space Conditioning Capacities for Reporting Purposes
a. When reporting rated capacities, round them off as specified
in Sec. 430.23 (for a single unit) and in 10 CFR 429.16 (for a
sample).
b. For the capacities used to perform the calculations in
section 4 of this appendix, however, round only to the nearest
integer.
3.13 Laboratory Testing To Determine Off Mode Average Power Ratings
Voltage tolerances: As a percentage of reading, test operating
tolerance must be 2.0 percent and test condition tolerance must be
1.5 percent (see section 1.2 of this appendix for definitions of
these tolerances).
Conduct one of the following tests: If the central air
conditioner or heat pump lacks a compressor crankcase heater,
perform the test in section 3.13.1 of this appendix; if the central
air conditioner or heat pump has a compressor crankcase heater that
lacks controls and is not self-regulating, perform the test in
section 3.13.1 of this appendix; if the central air conditioner or
heat pump has a crankcase heater with a fixed power input controlled
with a thermostat that measures ambient temperature and whose
sensing element temperature is not affected by the heater, perform
the test in section 3.13.1 of this appendix; if the central air
conditioner or heat pump has a compressor crankcase heater equipped
with self-regulating control or with controls for which the sensing
element temperature is affected by the heater, perform the test in
section 3.13.2 of this appendix.
3.13.1 This test determines the off mode average power rating
for central air conditioners and heat pumps that lack a
[[Page 58247]]
compressor crankcase heater, or have a compressor crankcase heating
system that can be tested without control of ambient temperature
during the test. This test has no ambient condition requirements.
a. Test Sample Set-up and Power Measurement: For coil-only
systems, provide a furnace or modular blower that is compatible with
the system to serve as an interface with the thermostat (if used for
the test) and to provide low-voltage control circuit power. Make all
control circuit connections between the furnace (or modular blower)
and the outdoor unit as specified by the manufacturer's installation
instructions. Measure power supplied to both the furnace or modular
blower and power supplied to the outdoor unit. Alternatively,
provide a compatible transformer to supply low-voltage control
circuit power, as described in section 2.2.d of this appendix.
Measure transformer power, either supplied to the primary winding or
supplied by the secondary winding of the transformer, and power
supplied to the outdoor unit. For blower coil and single-package
systems, make all control circuit connections between components as
specified by the manufacturer's installation instructions, and
provide power and measure power supplied to all system components.
b. Configure Controls: Configure the controls of the central air
conditioner or heat pump so that it operates as if connected to a
building thermostat that is set to the OFF position. Use a
compatible building thermostat if necessary to achieve this
configuration. For a thermostat-controlled crankcase heater with a
fixed power input, bypass the crankcase heater thermostat if
necessary to energize the heater.
c. Measure P2x: If the unit has a crankcase heater time delay,
make sure that time-delay function is disabled or wait until delay
time has passed. Determine the average power from non-zero value
data measured over a 5-minute interval of the non-operating central
air conditioner or heat pump and designate the average power as P2x,
the heating season total off mode power.
d. Measure Px for coil-only split systems and for blower coil
split systems for which a furnace or a modular blower is the
designated air mover: Disconnect all low-voltage wiring for the
outdoor components and outdoor controls from the low-voltage
transformer. Determine the average power from non-zero value data
measured over a 5-minute interval of the power supplied to the
(remaining) low-voltage components of the central air conditioner or
heat pump, or low-voltage power, Px. This power measurement does not
include line power supplied to the outdoor unit. It is the line
power supplied to the air mover, or, if a compatible transformer is
used instead of an air mover, it is the line power supplied to the
transformer primary coil. If a compatible transformer is used
instead of an air mover and power output of the low-voltage
secondary circuit is measured, Px is zero.
e. Calculate P2: Set the number of compressors equal to the
unit's number of single-stage compressors plus 1.75 times the unit's
number of compressors that are not single-stage.
For single-package systems and blower coil split systems for
which the designated air mover is not a furnace or modular blower,
divide the heating season total off mode power (P2x) by the number
of compressors to calculate P2, the heating season per-compressor
off mode power. Round P2 to the nearest watt. The expression for
calculating P2 is as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.038
For coil-only split systems and blower coil split systems for
which a furnace or a modular blower is the designated air mover,
subtract the low-voltage power (Px) from the heating season total
off mode power (P2x) and divide by the number of compressors to
calculate P2, the heating season per-compressor off mode power.
Round P2 to the nearest watt. The expression for calculating P2 is
as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.039
f. Shoulder-season per-compressor off mode power, P1: If the
system does not have a crankcase heater, has a crankcase heater
without controls that is not self-regulating, or has a value for the
crankcase heater turn-on temperature (as certified to DOE) that is
higher than 71[emsp14][deg]F, P1 is equal to P2.
Otherwise, de-energize the crankcase heater (by removing the
thermostat bypass or otherwise disconnecting only the power supply
to the crankcase heater) and repeat the measurement as described in
section 3.13.1.c of this appendix. Designate the measured average
power as P1x, the shoulder season total off mode power.
Determine the number of compressors as described in section
3.13.1.e of this appendix.
For single-package systems and blower coil systems for which the
designated air mover is not a furnace or modular blower, divide the
shoulder season total off mode power (P1x) by the number of
compressors to calculate P1, the shoulder season per-compressor off
mode power. Round P1 to the nearest watt. The expression for
calculating P1 is as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.040
For coil-only split systems and blower coil split systems for
which a furnace or a modular blower is the designated air mover,
subtract the low-voltage power (Px) from the shoulder season total
off mode power (P1x) and divide by the number of compressors to
calculate P1, the shoulder season per-compressor off mode power.
Round P1 to the nearest watt. The expression for calculating P1 is
as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.041
3.13.2 This test determines the off mode average power rating
for central air conditioners and heat pumps for which ambient
temperature can affect the measurement of crankcase heater power.
a. Test Sample Set-up and Power Measurement: set up the test and
measurement as described in section 3.13.1.a of this appendix.
b. Configure Controls: Position a temperature sensor to measure
the outdoor dry-bulb temperature in the air between 2 and 6 inches
from the crankcase heater control temperature sensor or, if no such
temperature sensor exists, position it in the air between 2 and 6
inches from the crankcase heater. Utilize the temperature
measurements from this sensor for this portion of the test
procedure. Configure the controls of the central air conditioner or
heat pump so that it operates as if connected to a building
thermostat that is set to the OFF position. Use a compatible
building thermostat if necessary to achieve this configuration.
Conduct the test after completion of the B, B1, or
B2 test. Alternatively, start the test when the outdoor
dry-bulb temperature is at 82 [deg]F and the temperature of the
compressor shell (or temperature of each compressor's shell if there
is more than one compressor) is at least 81 [deg]F. Then adjust the
outdoor temperature and achieve an outdoor dry-bulb temperature of
72 [deg]F. If the unit's compressor has no sound blanket, wait at
least 4 hours after the outdoor temperature reaches 72 [deg]F.
Otherwise, wait at least 8 hours after the outdoor temperature
reaches 72 [deg]F. Maintain this temperature within +/-2 [deg]F
while the compressor temperature equilibrates and while making the
power measurement, as described in section 3.13.2.c of this
appendix.
c. Measure P1x: If the unit has a crankcase heater time delay,
make sure that time-delay function is disabled or wait until delay
time has passed. Determine the average power from non-zero value
data measured over a 5-minute interval of the non-operating central
air conditioner or heat pump and designate the average power as P1x,
the shoulder season total off mode power. For units with crankcase
heaters which operate during this part of the test and whose
controls cycle or vary crankcase heater power over time, the test
period shall consist of three complete crankcase heater cycles or 18
hours, whichever comes first. Designate the average power over the
test period as P1x, the shoulder season total off mode power.
d. Reduce outdoor temperature: Approach the target outdoor dry-
bulb temperature by adjusting the outdoor temperature. This target
temperature is five degrees Fahrenheit less than the temperature
certified by the manufacturer as the temperature at which the
crankcase heater turns on. If the unit's compressor has no sound
blanket, wait at least 4 hours after the outdoor temperature reaches
the target temperature. Otherwise, wait at least 8 hours after the
outdoor temperature reaches the target temperature. Maintain the
target temperature within +/-2 [deg]F while the compressor
temperature equilibrates and while making the power measurement, as
described in section 3.13.2.e of this appendix.
e. Measure P2x: If the unit has a crankcase heater time delay,
make sure that time-delay function is disabled or wait until delay
time has passed. Determine the average non-zero power of the non-
operating central air conditioner or heat pump over a 5-minute
interval and designate it as P2x, the heating season total off mode
power. For units with
[[Page 58248]]
crankcase heaters whose controls cycle or vary crankcase heater
power over time, the test period shall consist of three complete
crankcase heater cycles or 18 hours, whichever comes first.
Designate the average power over the test period as P2x, the heating
season total off mode power.
f. Measure Px for coil-only split systems and for blower coil
split systems for which a furnace or modular blower is the
designated air mover: Disconnect all low-voltage wiring for the
outdoor components and outdoor controls from the low-voltage
transformer. Determine the average power from non-zero value data
measured over a 5-minute interval of the power supplied to the
(remaining) low-voltage components of the central air conditioner or
heat pump, or low-voltage power, Px. This power measurement does not
include line power supplied to the outdoor unit. It is the line
power supplied to the air mover, or, if a compatible
transformer is used instead of an air mover, it is the line power
supplied to the transformer primary coil. If a compatible
transformer is used instead of an air mover and power output of the
low-voltage secondary circuit is measured, Px is zero.
g. Calculate P1:
Set the number of compressors equal to the unit's number of
single-stage compressors plus 1.75 times the unit's number of
compressors that are not single-stage.
For single-package systems and blower coil split systems for
which the air mover is not a furnace or modular blower, divide the
shoulder season total off mode power (P1x) by the number of
compressors to calculate P1, the shoulder season per-compressor off
mode power. Round to the nearest watt. The expression for
calculating P1 is as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.042
For coil-only split systems and blower coil split systems for
which a furnace or a modular blower is the designated air mover,
subtract the low-voltage power (Px) from the shoulder season total
off mode power (P1x) and divide by the number of compressors to
calculate P1, the shoulder season per-compressor off mode power.
Round to the nearest watt. The expression for calculating P1 is as
follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.043
h. Calculate P2:
Determine the number of compressors as described in section
3.13.2.g of this appendix.
For, single-package systems and blower coil split systems for
which the air mover is not a furnace, divide the heating season
total off mode power (P2x) by the number of compressors to calculate
P2, the heating season per-compressor off mode power. Round to the
nearest watt. The expression for calculating P2 is as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.044
For coil-only split systems and blower coil split systems for
which a furnace or a modular blower is the designated air mover,
subtract the low-voltage power (Px) from the heating season total
off mode power (P2x) and divide by the number of compressors to
calculate P2, the heating season per-compressor off mode power.
Round to the nearest watt. The expression for calculating P2 is as
follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.045
4. Calculations of Seasonal Performance Descriptors
4.1 Seasonal Energy Efficiency Ratio (SEER) Calculations.
Calculate SEER as follows: For equipment covered under sections
4.1.2, 4.1.3, and 4.1.4 of this appendix, evaluate the seasonal
energy efficiency ratio,
[GRAPHIC] [TIFF OMITTED] TP24AU16.046
[GRAPHIC] [TIFF OMITTED] TP24AU16.047
Tj = the outdoor bin temperature, [deg]F. Outdoor
temperatures are grouped or ``binned.'' Use bins of 5 [deg]F with
the 8 cooling season bin temperatures being 67, 72, 77, 82, 87, 92,
97, and 102 [deg]F.
j = the bin number. For cooling season calculations, j ranges from 1
to 8.
Additionally, for sections 4.1.2, 4.1.3, and 4.1.4 of this appendix,
use a building cooling load, BL(Tj). When referenced,
evaluate BL(Tj) for cooling using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.048
[[Page 58249]]
Where,
Qc\k=2\(95) = the space cooling capacity determined from
the A2 test and calculated as specified in section 3.3 of
this appendix, Btu/h.
1.1 = sizing factor, dimensionless.
The temperatures 95 [deg]F and 65 [deg]F in the building load
equation represent the selected outdoor design temperature and the
zero-load base temperature, respectively.
V is a factor equal to 0.93 for variable-speed heat pumps and
otherwise equal to 1.0.
4.1.1 SEER Calculations for a Blower Coil System Having a Single-Speed
Compressor and Either a Fixed-Speed Indoor Blower or a Constant-Air-
Volume-Rate Indoor Blower, or a Coil-Only System Air Conditioner or
Heat Pump
a. Evaluate the seasonal energy efficiency ratio, expressed in
units of Btu/watt-hour, using:
SEER = PLF(0.5)* EERB
Where:
[GRAPHIC] [TIFF OMITTED] TP24AU16.049
PLF(0.5) = 1 - 0.5 [middot] CD\c\, the part-load
performance factor evaluated at a cooling load factor of 0.5,
dimensionless.
b. Refer to section 3.3 of this appendix regarding the
definition and calculation of Qc(82) and
Ec(82). Evaluate the cooling mode cyclic degradation
factor CD\c\ as specified in section 3.5.3 of this
appendix.
4.1.2 SEER Calculations for an Air Conditioner or Heat Pump Having a
Single-Speed Compressor and a Variable-Speed Variable-Air-Volume-Rate
Indoor Blower
4.1.2.1 Units Covered by Section 3.2.2.1 of This Appendix Where
Indoor Blower Capacity Modulation Correlates With the Outdoor Dry
Bulb Temperature. The manufacturer must provide information on how
the indoor air volume rate or the indoor blower speed varies over
the outdoor temperature range of 67 [deg]F to 102 [deg]F. Calculate
SEER using Equation 4.1-1. Evaluate the quantity
qc(Tj)/N in Equation 4.1-1 using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.050
Qc(Tj) = the space cooling capacity of the
test unit when operating at outdoor temperature, Tj, Btu/
h.
nj/N = fractional bin hours for the cooling season; the
ratio of the number of hours during the cooling season when the
outdoor temperature fell within the range represented by bin
temperature Tj to the total number of hours in the
cooling season, dimensionless.
a. For the space cooling season, assign nj/N as
specified in Table 18. Use Equation 4.1-2 to calculate the building
load, BL(Tj). Evaluate Qc(Tj)
using,
[[Page 58250]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.051
the space cooling capacity of the test unit at outdoor temperature
Tj if operated at the Cooling full-load air volume rate,
Btu/h.
b. For units where indoor blower speed is the primary control
variable, FPc\k=1\ denotes the fan speed used during the
required A1 and B1 tests (see section 3.2.2.1
of this appendix), FPc\k=2\ denotes the fan speed used
during the required A2 and B2 tests, and
FPc(Tj) denotes the fan speed used by the unit
when the outdoor temperature equals Tj. For units where
indoor air volume rate is the primary control variable, the three
FPc's are similarly defined only now being expressed in
terms of air volume rates rather than fan speeds. Refer to sections
3.2.2.1, 3.1.4 to 3.1.4.2, and 3.3 of this appendix regarding the
definitions and calculations of Qc\k=1\(82),
Qc\k=1\(95), Qc\k=2\(82), and
Qc\k=2\(95).
[GRAPHIC] [TIFF OMITTED] TP24AU16.052
Where:
PLFj = 1 - CD\c\ [middot] [1 -
X(Tj)], the part load factor, dimensionless.
Ec(Tj) = the electrical power consumption of
the test unit when operating at outdoor temperature Tj,
W.
c. The quantities X(Tj) and nj/N are the
same quantities as used in Equation 4.1.2-1. Evaluate the cooling
mode cyclic degradation factor CD\c\ as specified in
section 3.5.3 of this appendix.
d. Evaluate Ec(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.053
[[Page 58251]]
e. The parameters FPc\k=1\, and FPc\k=2\,
and FPc(Tj) are the same quantities that are
used when evaluating Equation 4.1.2-2. Refer to sections 3.2.2.1,
3.1.4 to 3.1.4.2, and 3.3 of this appendix regarding the definitions
and calculations of Ec\k=1\(82), Ec\k=1\(95),
Ec\k=2\(82), and Ec\k=2\(95).
4.1.2.2 Units Covered by Section 3.2.2.2 of this Appendix Where Indoor
Blower Capacity Modulation is Used to Adjust the Sensible to Total
Cooling Capacity Ratio. Calculate SEER as Specified in Section 4.1.1 of
This Appendix
4.1.3 SEER Calculations for an Air Conditioner or Heat Pump Having a
Two-Capacity Compressor
Calculate SEER using Equation 4.1-1. Evaluate the space cooling
capacity, Qck=1 (Tj), and
electrical power consumption, Eck=1
(Tj), of the test unit when operating at low compressor
capacity and outdoor temperature Tj using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.054
where Qck=1(82) and
Eck=1(82) are determined from the
B1 test, Qck=1(67) and
Eck=1(67) are determined from the
F1 test, and all four quantities are calculated as
specified in section 3.3 of this appendix. Evaluate the space
cooling capacity, Qck=2 (Tj), and
electrical power consumption, Eck=2
(Tj), of the test unit when operating at high compressor
capacity and outdoor temperature Tj using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.055
where Qck=2(95) and
Eck=2(95) are determined from the
A2 test, Qck=2(82), and
Eck=2(82), are determined from the
B2 test, and all are calculated as specified in section
3.3 of this appendix.
The calculation of Equation 4.1-1 quantities
qc(Tj)/N and ec(Tj)/N
differs depending on whether the test unit would operate at low
capacity (section 4.1.3.1 of this appendix), cycle between low and
high capacity (section 4.1.3.2 of this appendix), or operate at high
capacity (sections 4.1.3.3 and 4.1.3.4 of this appendix) in
responding to the building load. For units that lock out low
capacity operation at higher outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations are used. Use Equation 4.1-2 to calculate the building
load, BL(Tj), for each temperature bin.
4.1.3.1 Steady-state space cooling capacity at low compressor
capacity is greater than or equal to the building cooling load at
temperature Tj,
Qck=1(Tj) >=BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.056
Where:
Xk=1(Tj) = BL(Tj)/
Qck=1(Tj), the cooling mode low
capacity load factor for temperature bin j, dimensionless.
PLFj = 1 - CDc [middot] [1 -
Xk=1(Tj)], the part load factor,
dimensionless.
nj/N = fractional bin hours for the cooling season; the
ratio of the number of hours during the cooling season when the
outdoor temperature fell within the range represented by bin
temperature Tj to the total number of hours in the
cooling season, dimensionless.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. Use Equations 4.1.3-1 and 4.1.3-2,
respectively, to evaluate Qck=1(Tj)
and Eck=1(Tj). Evaluate the cooling
mode cyclic degradation factor CDc as
specified in section 3.5.3 of this appendix.
Table 18--Distribution of Fractional Hours Within Cooling Season Temperature Bins
----------------------------------------------------------------------------------------------------------------
Representative Fraction of of
Bin number, j Bin temperature temperature for total temperature
range [deg]F bin [deg]F bin hours, nj/N
----------------------------------------------------------------------------------------------------------------
1................................................... 65-69 67 0.214
2................................................... 70-74 72 0.231
3................................................... 75-79 77 0.216
4................................................... 80-84 82 0.161
5................................................... 85-89 87 0.104
6................................................... 90-94 92 0.052
7................................................... 95-99 97 0.018
8................................................... 100-104 102 0.004
----------------------------------------------------------------------------------------------------------------
[[Page 58252]]
4.1.3.2 Unit alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building cooling load at
temperature Tj,
Qck=1(Tj) j)
ck=2(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.057
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. Use Equations 4.1.3-1 and 4.1.3-2,
respectively, to evaluate Qck=1(Tj)
and Eck=1(Tj). Use Equations 4.1.3-
3 and 4.1.3-4, respectively, to evaluate
Qck=2(Tj) and
Eck=2(Tj).
4.1.3.3 Unit only operates at high (k=2) compressor capacity at
temperature Tj and its capacity is greater than the
building cooling load, BL(Tj)
ck=2(Tj). This section applies to
units that lock out low compressor capacity operation at higher
outdoor temperatures.
[GRAPHIC] [TIFF OMITTED] TP24AU16.058
Where,
Xk=2(Tj) = BL(Tj)/
Qck=2(Tj), the cooling mode high
capacity load factor for temperature bin j, dimensionless.
PLFj = 1 - CDc(k = 2) * [1 - Xk=2(Tj)], the part load
factor, dimensionless.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. Use Equations 4.1.3-3 and 4.1.3-4,
respectively, to evaluate Qck=2
(Tj) and Eck=2 (Tj). If
the C2 and D2 tests described in section 3.2.3
and Table 6 of this appendix are not conducted, set
CDc (k=2) equal to the default value specified
in section 3.5.3 of this appendix.
4.1.3.4 Unit must operate continuously at high (k=2) compressor
capacity at temperature Tj, BL(Tj)
>=Qck=2(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.059
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. Use Equations 4.1.3-3 and 4.1.3-4,
respectively, to evaluate Qck=2(Tj)
and Eck=2(Tj).
4.1.4 SEER Calculations for an Air Conditioner or Heat Pump Having a
Variable-Speed Compressor
Calculate SEER using Equation 4.1-1. Evaluate the space cooling
capacity, Qck=1(Tj), and electrical
power consumption, Eck=1(Tj), of
the test unit when operating at minimum compressor speed and outdoor
temperature Tj. Use,
[GRAPHIC] [TIFF OMITTED] TP24AU16.060
where Qck=1(82) and
Eck=1(82) are determined from the
B1 test, Qck=1(67) and
Eck=1(67) are determined from the F1 test, and
all four quantities are calculated as specified in section 3.3 of
this appendix. Evaluate the space cooling capacity,
Qck=2(Tj), and electrical power
consumption, Eck=2(Tj), of the test
unit when operating at full compressor speed and outdoor temperature
Tj. Use Equations 4.1.3-3 and 4.1.3-4, respectively,
where Qck=2(95) and
Eck=2(95) are determined from the
A2 test, Qck=2(82) and
Eck=2(82) are determined from the
B2 test, and all four quantities are calculated as
specified in section 3.3 of this appendix.
[[Page 58253]]
Calculate the space cooling capacity,
Qck=v(Tj), and electrical power
consumption, Eck=v(Tj), of the test
unit when operating at outdoor temperature Tj and the
intermediate compressor speed used during the section 3.2.4 (and
Table 7) EV test of this appendix using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.061
where Qck=v(87) and
Eck=v(87) are determined from the
EV test and calculated as specified in section 3.3 of
this appendix. Approximate the slopes of the k=v intermediate speed
cooling capacity and electrical power input curves, MQ
and ME, as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.062
Use Equations 4.1.4-1 and 4.1.4-2, respectively, to calculate
Qck=1(87) and Eck=1(87).
4.1.4.1 Steady-state space cooling capacity when operating at
minimum compressor speed is greater than or equal to the building
cooling load at temperature Tj,
Qck=1(Tj) >=BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.063
Where:
Xk=1(Tj) = BL(Tj)/
Qck=1(Tj), the cooling mode minimum
speed load factor for temperature bin j, dimensionless.
PLFj = 1 - CDc - [1 -
Xk=1(Tj)], the part load factor,
dimensionless.
nj/N = fractional bin hours for the cooling season; the
ratio of the number of hours during the cooling season when the
outdoor temperature fell within the range represented by bin
temperature Tj to the total number of hours in the
cooling season, dimensionless.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18. Use Equations 4.1.3-1 and 4.1.3-2,
respectively, to evaluate Qck=1
(Tj) and Eck=1 (Tj).
Evaluate the cooling mode cyclic degradation factor
CDc as specified in section 3.5.3 of this
appendix.
4.1.4.2 Unit operates at an intermediate compressor speed (k=i)
in order to match the building cooling load at temperature
Tj, Qck=1(Tj)
j) ck=2(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.064
Where:
Qck=i(Tj) = BL(Tj), the
space cooling capacity delivered by the unit in matching the
building load at temperature Tj, Btu/h. The matching
occurs with the unit operating at compressor speed k = i.
[GRAPHIC] [TIFF OMITTED] TP24AU16.130
EERk=i(Tj) = the steady-state energy
efficiency ratio of the test unit when operating at a compressor
speed of k = i and temperature Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 18 of this section. For each temperature
bin where the unit operates at an intermediate compressor speed,
determine the energy efficiency ratio
EERk=i(Tj) using the following equations,
For each temperature bin where
Qck=1(Tj) j)
ck=v>(Tj),
[[Page 58254]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.065
Where:
EERk=1(Tj) is the steady-state energy
efficiency ratio of the test unit when operating at minimum
compressor speed and temperature Tj, Btu/h per W, calculated using
capacity Qck=1(Tj) calculated using
Equation 4.1.4-1 and electrical power consumption
Eck=1(Tj) calculated using Equation
4.1.4-2;
EERk=v(Tj) is the steady-state energy
efficiency ratio of the test unit when operating at intermediate
compressor speed and temperature Tj, Btu/h per W, calculated using
capacity Qck=v(Tj) calculated using
Equation 4.1.4-3 and electrical power consumption
Eck=v(Tj) calculated using Equation
4.1.4-4;
EERk=2(Tj) is the steady-state energy
efficiency ratio of the test unit when operating at full compressor
speed and temperature Tj, Btu/h per W, calculated using capacity
Qck=2(Tj) and electrical power
consumption Eck=2(Tj), both
calculated as described in section 4.1.4; and
BL(Tj) is the building cooling load at temperature
Tj, Btu/h.
4.1.4.3 Unit must operate continuously at full (k=2) compressor
speed at temperature Tj, BL(Tj)
>=Qck=2(Tj). Evaluate the Equation
4.1-1 quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.066
as specified in section 4.1.3.4 of this appendix with the
understanding that Qck=2(Tj) and
Eck=2(Tj) correspond to full
compressor speed operation and are derived from the results of the
tests specified in section 3.2.4 of this appendix.
4.1.5 SEER calculations for an air conditioner or heat pump
having a single indoor unit with multiple indoor blowers.
Calculate SEER using Eq. 4.1-1, where qc(Tj)/N and
ec(Tj)/N are evaluated as specified in the applicable
subsection.
4.1.5.1 For multiple indoor blower systems that are connected to
a single, single-speed outdoor unit.
a. Calculate the space cooling capacity, Qck=1(Tj),
and electrical power consumption, Eck=1(Tj), of the test
unit when operating at the cooling minimum air volume rate and
outdoor temperature Tj using the equations given in
section 4.1.2.1 of this appendix. Calculate the space cooling
capacity, Qck=2(Tj), and electrical power consumption,
Eck=2(Tj), of the test unit when operating at the cooling
full-load air volume rate and outdoor temperature Tj
using the equations given in section 4.1.2.1 of this appendix. In
evaluating the section 4.1.2.1 equations, determine the quantities
Qck=1(82) and Eck=1(82) from the B1 test,
Qck=1(95) and Eck=1(95) from the Al test,
Qck=2(82) and Eck=2(82) from the B2 test, and
Qck=2(95) and Eck=2(95) from the A2 test.
Evaluate all eight quantities as specified in section 3.3. Refer to
section 3.2.2.1 and Table 5 for additional information on the four
referenced laboratory tests.
b. Determine the cooling mode cyclic degradation coefficient,
CDc, as per sections 3.2.2.1 and 3.5 to 3.5.3
of this appendix. Assign this same value to
CDc(K=2).
c. Except for using the above values of Qck=1(Tj),
Eck=1(Tj), Eck=2(Tj), Qck=2(Tj),
CDc, and CDc (K=2),
calculate the quantities qc(Tj)/N and
ec(Tj)/N as specified in section 4.1.3.1 of
this appendix for cases where Qck=1(Tj) >=
BL(Tj). For all other outdoor bin temperatures,
Tj, calculate qc(Tj)/N and ec(Tj)/N
as specified in section 4.1.3.3 of this appendix if
Qck=2(Tj) > BL (Tj) or as specified in section
4.1.3.4 of this appendix if Qck=2(Tj) <=
BL(Tj).
4.1.5.2 For multiple indoor blower systems that are connected to
either a lone outdoor unit having a two-capacity compressor or two
separate but identical model single-speed outdoor units. Calculate
the quantities qc(Tj)/N and ec(Tj)/N as
specified in section 4.1.3 of this appendix.
4.2 Heating Seasonal Performance Factor (HSPF) Calculations
Unless an approved alternative efficiency determination method
is used, as set forth in 10 CFR 429.70(e). Calculate HSPF as
follows: Six generalized climatic regions are depicted in Figure 1
and otherwise defined in Table 19. For each of these regions and for
each applicable standardized design heating requirement, evaluate
the heating seasonal performance factor using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.067
Where:
eh(Tj)/N = The ratio of the electrical energy
consumed by the heat pump during periods of the heating season when
the outdoor temperature fell within the range represented by bin
temperature Tj to the total number of hours in the
heating season (N), W. For heat pumps having a heat comfort
controller, this ratio may also include electrical energy used by
resistive elements to maintain a minimum air delivery temperature
(see 4.2.5).
RH(Tj)/N = The ratio of the electrical energy used for
resistive space heating during periods when the outdoor temperature
fell within the range represented by bin temperature Tj
to the total number of hours in the heating season (N), W. Except as
noted in section 4.2.5 of this appendix, resistive space heating is
modeled as being used to meet that portion of the building load that
the heat pump does not meet because of insufficient capacity or
because the heat pump automatically turns off at the lowest outdoor
temperatures. For heat pumps having a heat comfort controller, all
or part of the electrical energy used by resistive heaters at a
particular bin temperature may be reflected in
eh(Tj)/N (see section 4.2.5 of this appendix).
Tj = the outdoor bin temperature, [deg]F. Outdoor
temperatures are ``binned'' such that calculations are only
performed based one temperature within the bin. Bins of 5 [deg]F are
used.
nj/N = Fractional bin hours for the heating season; the
ratio of the number of hours during the heating season when the
outdoor temperature fell within the range represented by bin
temperature Tj to the total number of hours in the
heating season, dimensionless. Obtain nj/N values from
Table 19.
j = the bin number, dimensionless.
J = for each generalized climatic region, the total number of
temperature bins, dimensionless. Referring to Table 19, J is the
highest bin number (j) having a nonzero entry for the fractional bin
hours for the generalized climatic region of interest.
[[Page 58255]]
Fdef = the demand defrost credit described in section
3.9.2 of this appendix, dimensionless.
BL(Tj) = the building space conditioning load
corresponding to an outdoor temperature of Tj; the
heating season building load also depends on the generalized
climatic region's outdoor design temperature and the design heating
requirement, Btu/h.
Table 19--Generalized Climatic Region Information
----------------------------------------------------------------------------------------------------------------
Region No. I II III IV V * VI
----------------------------------------------------------------------------------------------------------------
Heating Load Hours, HLH........... 493 857 1,280 1,701 2,202 1,842
Outdoor Design Temperature, TOD... 37 27 17 5 -10 30
Heating Load Line Equation Slope 1.10 1.06 1.29 1.15 1.16 1.11
Factor, C........................
Variable Speed Slope Factor, CVS.. 1.03 0.99 1.20 1.07 1.08 1.03
Zero-Load Temperature, Tzl........ 58 57 56 55 55 57
-----------------------------------------------------------------------------
j Tj ([deg]F)..................... Fractional Bin Hours, nj/N
-----------------------------------------------------------------------------
1 62.............................. .291 .215 .153 .132 .106 .113
2 57.............................. .239 .189 .142 .111 .092 .206
3 52.............................. .194 .163 .138 .103 .086 .215
4 47.............................. .129 .143 .137 .093 .076 .204
5 42.............................. .081 .112 .135 .100 .078 .141
6 37.............................. .041 .088 .118 .109 .087 .076
7 32.............................. .019 .056 .092 .126 .102 .034
8 27.............................. .005 .024 .047 .087 .094 .008
9 22.............................. .001 .008 .021 .055 .074 .003
10 17............................. 0 .002 .009 .036 .055 0
11 12............................. 0 0 .005 .026 .047 0
12 7.............................. 0 0 .002 .013 .038 0
13 2.............................. 0 0 .001 .006 .029 0
14 -3............................. 0 0 0 .002 .018 0
15 -8............................. 0 0 0 .001 .010 0
16 -13............................ 0 0 0 0 .005 0
17 -18............................ 0 0 0 0 .002 0
18 -23............................ 0 0 0 0 .001 0
----------------------------------------------------------------------------------------------------------------
* Pacific Coast Region.
Evaluate the building heating load using
[GRAPHIC] [TIFF OMITTED] TP24AU16.068
Where,
Tj = the outdoor bin temperature, [deg]F
Tzl = the zero-load temperature, [deg]F, which varies by
climate region according to Table 19
TOD = the outdoor design temperature, [deg]F, which
varies by climate region according to Table 19
C = the slope (adjustment) factor, which varies by climate region
according to Table 19
Qc(95 [deg]F) = the cooling capacity at 95 [deg]F determined from
the A or A2 test, Btu/h
For heating-only heat pump units, replace Qc(95 [deg]F) in
Equation 4.2-2 with Qh(47 [deg]F)
Qh(47 [deg]F) = the heating capacity at 47 [deg]F determined from
the H, H12 or H1N test, Btu/h.
a. For all heat pumps, HSPF accounts for the heating delivered
and the energy consumed by auxiliary resistive elements when
operating below the balance point. This condition occurs when the
building load exceeds the space heating capacity of the heat pump
condenser. For HSPF calculations for all heat pumps, see either
section 4.2.1, 4.2.2, 4.2.3, or 4.2.4 of this appendix, whichever
applies.
b. For heat pumps with heat comfort controllers (see section 1.2
of this appendix, Definitions), HSPF also accounts for resistive
heating contributed when operating above the heat-pump-plus-comfort-
controller balance point as a result of maintaining a minimum supply
temperature. For heat pumps having a heat comfort controller, see
section 4.2.5 of this appendix for the additional steps required for
calculating the HSPF.
4.2.1 Additional Steps for Calculating the HSPF of a Blower Coil
System Heat Pump Having a Single-Speed Compressor and Either a
Fixed-Speed Indoor Blower or a Constant-Air-Volume-Rate Indoor
Blower Installed, or a Coil-Only System Heat Pump.
[[Page 58256]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.069
whichever is less; the heating mode load factor for temperature bin
j, dimensionless.
Qh(Tj) = the space heating capacity of the
heat pump when operating at outdoor temperature Tj, Btu/
h.
Eh(Tj) = the electrical power consumption of
the heat pump when operating at outdoor temperature Tj,
W.
[delta](Tj) = the heat pump low temperature cut-out
factor, dimensionless.
PLFj = 1 - CDh [middot] [1 -
X(Tj)] the part load factor, dimensionless.
Use Equation 4.2-2 to determine BL(Tj). Obtain
fractional bin hours for the heating season, nj/N, from
Table 19. Evaluate the heating mode cyclic degradation factor
CDh as specified in section 3.8.1 of this
appendix.
Determine the low temperature cut-out factor using
[GRAPHIC] [TIFF OMITTED] TP24AU16.070
Where:
Toff = the outdoor temperature when the compressor is
automatically shut off, [deg]F. (If no such temperature exists,
Tj is always greater than Toff and
Ton).
Ton = the outdoor temperature when the compressor is
automatically turned back on, if applicable, following an automatic
shut-off, [deg]F.
Calculate Qh(Tj) and
Eh(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.071
where Qh(47) and Eh(47) are determined from
the H1 test and calculated as specified in section 3.7 of this
appendix; Qh(35) and Eh(35) are determined
from the H2 test and calculated as specified in section 3.9.1 of
this appendix; and Qh(17) and Eh(17) are
determined from the H3 test and calculated as specified in section
3.10 of this appendix.
4.2.2 Additional Steps for Calculating the HSPF of a Heat Pump Having a
Single-Speed Compressor and a Variable-Speed, Variable-Air-Volume-Rate
Indoor Blower
The manufacturer must provide information about how the indoor
air volume rate or the indoor blower speed varies over the outdoor
temperature range of 65 [deg]F to -23 [deg]F. Calculate the
quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.072
in Equation 4.2-1 as specified in section 4.2.1 of this appendix
with the exception of
[[Page 58257]]
replacing references to the H1C test and section 3.6.1 of this
appendix with the H1C1 test and section 3.6.2 of this
appendix. In addition, evaluate the space heating capacity and
electrical power consumption of the heat pump
Qh(Tj) and Eh(Tj) using
[GRAPHIC] [TIFF OMITTED] TP24AU16.073
For units where indoor blower speed is the primary control
variable, FPh\k=1\ denotes the fan speed used during the
required H11 and H31 tests (see Table 11),
FPh\k=2\ denotes the fan speed used during the required
H12, H22, and H32 tests, and
FPh(Tj) denotes the fan speed used by the unit
when the outdoor temperature equals Tj. For units where
indoor air volume rate is the primary control variable, the three
FPh's are similarly defined only now being expressed in
terms of air volume rates rather than fan speeds. Determine
Qh\k=1\(47) and Eh\k=1\(47) from the
H11 test, and Qh\k=2\(47) and
Eh\k=2\(47) from the H12 test. Calculate all
four quantities as specified in section 3.7 of this appendix.
Determine Qh\k=1\(35) and Eh\k=1\(35) as
specified in section 3.6.2 of this appendix; determine
Qh\k=2\(35) and Eh\k=2\(35) and from the
H22 test and the calculation specified in section 3.9 of
this appendix. Determine Qh\k=1\(17) and
Eh\k=1\(17 from the H31 test, and
Qh\k=2\(17) and Eh\k=2\(17) from the
H32 test. Calculate all four quantities as specified in
section 3.10 of this appendix.
4.2.3 Additional Steps for Calculating the HSPF of a Heat Pump Having a
Two-Capacity Compressor
The calculation of the Equation 4.2-1 quantities differ
depending upon whether the heat pump would operate at low capacity
(section 4.2.3.1 of this appendix), cycle between low and high
capacity (section 4.2.3.2 of this appendix), or operate at high
capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in
responding to the building load. For heat pumps that lock out low
capacity operation at low outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations can be selected.
[GRAPHIC] [TIFF OMITTED] TP24AU16.074
a. Evaluate the space heating capacity and electrical power
consumption of the heat pump when operating at low compressor
capacity and outdoor temperature Tj using
[[Page 58258]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.075
b. Evaluate the space heating capacity and electrical power
consumption (Qh\k=2\(Tj) and
Eh\k=2\ (Tj)) of the heat pump when operating
at high compressor capacity and outdoor temperature Tj by solving
Equations 4.2.2-3 and 4.2.2-4, respectively, for k=2. Determine
Qh\k=1\(62) and Eh\k=1\(62) from the
H01 test, Qh\k=1\(47) and
Eh\k=1\(47) from the H11 test, and
Qh\k=2\(47) and Eh\k=2\(47) from the
H12 test. Calculate all six quantities as specified in
section 3.7 of this appendix. Determine Qh\k=2\(35) and
Eh\k=2\(35) from the H22 test and, if required
as described in section 3.6.3 of this appendix, determine
Qh\k=1\(35) and Eh\k=1\(35) from the
H21 test. Calculate the required 35 [deg]F quantities as
specified in section 3.9 in this appendix. Determine
Qh\k=2\(17) and Eh\k=2\(17) from the
H32 test and, if required as described in section 3.6.3
of this appendix, determine Qh\k=1\(17) and
Eh\k=1\(17) from the H31 test. Calculate the
required 17 [deg]F quantities as specified in section 3.10 of this
appendix.
4.2.3.1 Steady-state space heating capacity when operating at
low compressor capacity is greater than or equal to the building
heating load at temperature Tj,
Qh\k=1\(Tj) >=BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.076
Where:
X\k=1\(Tj) = BL(Tj)/
Qh\k=1\(Tj), the heating mode low capacity
load factor for temperature bin j, dimensionless.
PLFj = 1 - CD\h\ [middot] [1 -
X\k=1\(Tj)], the part load factor, dimensionless.
[delta]'(Tj) = the low temperature cutoff factor,
dimensionless.
Evaluate the heating mode cyclic degradation factor
CD\h\ as specified in section 3.8.1 of this appendix.
Determine the low temperature cut-out factor using
[GRAPHIC] [TIFF OMITTED] TP24AU16.077
where Toff and Ton are defined in section
4.2.1 of this appendix. Use the calculations given in section
4.2.3.3 of this appendix, and not the above, if:
a. The heat pump locks out low capacity operation at low outdoor
temperatures and
b. Tj is below this lockout threshold temperature.
4.2.3.2 Heat pump alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building heating load at a
temperature Tj, Qh\k=1\(Tj)
j) h\k=2\(Tj).
[[Page 58259]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.078
X\k=2\(Tj) = 1 - X\k=1\(Tj) the heating mode,
high capacity load factor for temperature bin j,
dimensionless.
Determine the low temperature cut-out factor,
[delta]'(Tj), using Equation 4.2.3-3.
4.2.3.3 Heat pump only operates at high (k=2) compressor
capacity at temperature Tj and its capacity is greater
than the building heating load, BL(Tj)
h\k=2\(Tj). This section applies to units
that lock out low compressor capacity operation at low outdoor
temperatures.
[GRAPHIC] [TIFF OMITTED] TP24AU16.079
Where:
X\k=2\(Tj) = BL(Tj)/
Qh\k=2\(Tj). PLFj = 1-CDh (k = 2) * [1-
Xk=2(Tj)]
If the H1C2 test described in section 3.6.3 and Table
12 of this appendix is not conducted, set CD\h\ (k=2)
equal to the default value specified in section 3.8.1 of this
appendix.
Determine the low temperature cut-out factor,
[delta](Tj), using Equation 4.2.3-3.
4.2.3.4 Heat pump must operate continuously at high (k=2)
compressor capacity at temperature Tj, BL(Tj)
>=Qh\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.080
a. Minimum Compressor Speed. Evaluate the space heating
capacity, Qh\k=1\(Tj), and electrical power
consumption, Eh\k=1\(Tj), of the heat pump
when operating at minimum compressor speed and outdoor temperature
Tj using
[GRAPHIC] [TIFF OMITTED] TP24AU16.081
[[Page 58260]]
where Qh\k=1\(62) and Eh\k=1\(62) are
determined from the H01 test, Qh\k=1\(47) and
Eh\k=1\(47) are determined from the H11 test,
and all four quantities are calculated as specified in section 3.7
of this appendix.
b. Minimum Compressor Speed for Minimum-speed-limiting Variable-
speed Heat Pumps: Evaluate the space heating capacity,
Qh\k=1\(Tj), and electrical power consumption,
Eh\k=1\(Tj), of the heat pump when operating
at minimum compressor speed and outdoor temperature Tj
using
[GRAPHIC] [TIFF OMITTED] TP24AU16.082
where Qh\k=1\(62) and Eh\k=1\(62) are
determined from the H01 test, Qh\k=1\(47) and
Eh\k=1\(47) are determined from the H11 test,
and all four quantities are calculated as specified in section 3.7
of this appendix; Qh\k=v\(35) and Eh\k=v\(35)
are determined from the H2v test and are calculated as
specified in section 3.9 of this appendix; and
Qh\k=v\(Tj) and
Eh\k=v\(Tj) are calculated using equations
4.2.4-5 and 4.2.4-6, respectively.
c. Full Compressor Speed for Heat Pumps for which the
H42 test is not Conducted.
Evaluate the space heating capacity,
Qh\k=2\(Tj), and electrical power consumption,
Eh\k=2\(Tj), of the heat pump when operating
at full compressor speed and outdoor temperature Tj by
solving Equations 4.2.2-3 and 4.2.2-4, respectively, for k=2, using
Qhcalc\k=2\(47) to represent Qh\k=2\(47) and
Ehcalc\k=2\(47) to represent Eh\k=2\(47) (see
section 3.6.4.b of this appendix regarding determination of the
capacity and power input used in the HSPF calculations to represent
the H12 Test). Determine Qh\k=2\(35) and
Eh\k=2\(35) from the H22 test and the
calculations specified in section 3.9 or, if the H22 test
is not conducted, by conducting the calculations specified in
section 3.6.4. Determine Qh\k=2\(17) and
Eh\k=2\(17) from the H32 test and the methods
specified in section 3.10 of this appendix.
d. Full Compressor Speed for Heat Pumps for which the
H42 test is Conducted.
For Tj above 17[emsp14][deg]F, evaluate the space
heating capacity, Qh\k=2\(Tj), and electrical
power consumption, Eh\k=2\(Tj), of the heat
pump when operating at full compressor speed as described above for
heat pumps for which the H42 is not conducted. For
Tj between 5[emsp14][deg]F and 17[emsp14][deg]F, evaluate
the space heating capacity, Qh\k=2\(Tj), and
electrical power consumption, Eh\k=2\(Tj), of
the heat pump when operating at full compressor speed using the
following equations:
[GRAPHIC] [TIFF OMITTED] TP24AU16.083
Determine Qh\k=2\(17) and Eh\k=2\(17) from
the H32 test, and Qh\k=2\(5) and
Eh\k=2\(5) from the H42 test, using the
methods specified in section 3.10 of this appendix for all four
values.
For Tj below 5[emsp14][deg]F, evaluate the space
heating capacity, Qh\k=2\(Tj), and electrical
power consumption, Eh\k=2\(Tj), of the heat
pump when operating at full compressor speed using the following
equations:
[GRAPHIC] [TIFF OMITTED] TP24AU16.084
[[Page 58261]]
Determine Qhcalc\k=2\(47) and
E;hcalc\k=2\(47) as described in section 3.6.4.b of this
appendix.
Determine Qh\k=2\(17) and Eh\k=2\(17) from
the H32 test, using the methods specified in section 3.10
of this appendix.
e. Intermediate Compressor Speed. Calculate the space heating
capacity, Qh\k=v\(Tj), and electrical power
consumption, of the heat pump when operating at outdoor temperature
Tj and the intermediate compressor speed used during the
section 3.6.4 H2V test using
Equation 4.2.4-5 Qh\k=v\(Tj) =
Qh\k=v\(35) + MQ * (Tj-35)
Equation 4.2.4-6 Eh\k=v\(Tj) =
Eh\k=v\(35) + ME * (Tj-35)
where Qh\k=v\(35) and Eh\k=v\(35) are
determined from the H2V test and calculated as specified
in section 3.9 of this appendix. Approximate the slopes of the k=v
intermediate speed heating capacity and electrical power input
curves, MQ and ME, as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.085
Use Equations 4.2.4-1 and 4.2.4-2, respectively, to calculate
Qh\k=1\(35) and Eh\k=1\(35), whether or not
the heat pump is a minimum-speed-limiting variable-speed heat pump.
4.2.4.1 Steady-state space heating capacity when operating at
minimum compressor speed is greater than or equal to the building
heating load at temperature Tj,
Qh\k=1\(Tj [gteqt]BL(Tj). Evaluate
the Equation 4.2-1 quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.086
as specified in section 4.2.3.1 of this appendix. Except now use
Equations 4.2.4-1 and 4.2.4-2 (for heat pumps that are not minimum-
speed-limiting) or Equations 4.3.4-3 and 4.2.4-4 (for minimum-speed-
limiting variable-speed heat pumps) to evaluate
Qh\k=1\(Tj) and
Eh\k=1\(Tj), respectively, and replace section
4.2.3.1 references to ``low capacity'' and section 3.6.3 of this
appendix with ``minimum speed'' and section 3.6.4 of this appendix.
Also, the last sentence of section 4.2.3.1 of this appendix does not
apply.
4.2.4.2 Heat pump operates at an intermediate compressor speed
(k=i) in order to match the building heating load at a temperature
Tj, Qh\k=1\(Tj) j)
h\k=2\(Tj). Calculate
[GRAPHIC] [TIFF OMITTED] TP24AU16.087
and [delta](Tj) is evaluated using Equation 4.2.3-3
while,
Qh\k=i\(Tj) = BL(Tj), the space
heating capacity delivered by the unit in matching the building load
at temperature (Tj), Btu/h. The matching occurs with the
heat pump operating at compressor speed k=i.
COP\k=i\(Tj) = the steady-state coefficient of
performance of the heat pump when operating at compressor speed k=i
and temperature Tj, dimensionless.
For each temperature bin where the heat pump operates at an
intermediate compressor speed, determine COP\k=i\(Tj)
using the following equations,
For each temperature bin where Qh\k=1\(Tj)
j) h\k=v\(Tj),
[[Page 58262]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.088
Where:
COPh\k=1\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at minimum compressor
speed and temperature Tj, dimensionless, calculated using capacity
Qh\k=1\(Tj) calculated using Equation 4.2.4-1
or 4.2.4-3 and electrical power consumption
Eh\k=1\(Tj) calculated using Equation 4.2.4-2
or 4.2.4-4;
COPh\k=v\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at intermediate
compressor speed and temperature Tj, dimensionless, calculated using
capacity Qh\k=v\(Tj) calculated using Equation
4.2.4-5 and electrical power consumption
Eh\k=v\(Tj) calculated using Equation 4.2.4-6;
COPh\k=2\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at full compressor
speed and temperature Tj, dimensionless, calculated using capacity
Qh\k=2\(Tj) and electrical power consumption
Eh\k=2\(Tj), both calculated as described in
section 4.2.4; and
BL(Tj) is the building heating load at temperature
Tj, Btu/h.
4.2.4.3 Heat pump must operate continuously at full (k=2)
compressor speed at temperature Tj, BL(Tj)
[gteqt]Qh\k=2\(Tj). Evaluate the Equation 4.2-
1 quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.089
as specified in section 4.2.3.4 of this appendix with the
understanding that Qh\k=2\(Tj) and
Eh\k=2\(Tj) correspond to full compressor
speed operation and are derived from the results of the specified
section 3.6.4 tests of this appendix.
4.2.5 Heat Pumps Having a Heat Comfort Controller
Heat pumps having heat comfort controllers, when set to maintain
a typical minimum air delivery temperature, will cause the heat pump
condenser to operate less because of a greater contribution from the
resistive elements. With a conventional heat pump, resistive heating
is only initiated if the heat pump condenser cannot meet the
building load (i.e., is delayed until a second stage call from the
indoor thermostat). With a heat comfort controller, resistive
heating can occur even though the heat pump condenser has adequate
capacity to meet the building load (i.e., both on during a first
stage call from the indoor thermostat). As a result, the outdoor
temperature where the heat pump compressor no longer cycles (i.e.,
starts to run continuously), will be lower than if the heat pump did
not have the heat comfort controller.
4.2.5.1 Blower Coil System Heat Pump Having a Heat Comfort Controller:
Additional Steps for Calculating the HSPF of a Heat Pump Having a
Single-Speed Compressor and Either a Fixed-Speed Indoor Blower or a
Constant-Air-Volume-Rate Indoor Blower Installed, or a Coil-Only System
Heat Pump
Calculate the space heating capacity and electrical power of the
heat pump without the heat comfort controller being active as
specified in section 4.2.1 of this appendix (Equations 4.2.1-4 and
4.2.1-5) for each outdoor bin temperature, Tj, that is
listed in Table 19. Denote these capacities and electrical powers by
using the subscript ``hp'' instead of ``h.'' Calculate the mass flow
rate (expressed in pounds-mass of dry air per hour) and the specific
heat of the indoor air (expressed in Btu/lbmda [middot]
[deg]F) from the results of the H1 test using:
[GRAPHIC] [TIFF OMITTED] TP24AU16.090
where Vis, Vimx, v'n (or
vn), and Wn are defined following Equation 3-
1. For each outdoor bin temperature listed in Table 19, calculate
the nominal temperature of the air leaving the heat pump condenser
coil using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.091
Evaluate eh(Tj/N), RH(Tj)/N,
X(Tj), PLFj, and [delta](Tj) as
specified in section 4.2.1 of this appendix. For each bin
calculation, use the space heating capacity and electrical power
from Case 1 or Case 2, whichever applies.
Case 1. For outdoor bin temperatures where
To(Tj) is equal to or greater than
TCC (the maximum supply temperature determined according
to section 3.1.9 of this appendix), determine
Qh(Tj) and Eh(Tj) as
specified in section 4.2.1 of this appendix (i.e.,
Qh(Tj) = Qhp(Tj) and
Ehp(Tj) = Ehp(Tj)).
Note: Even though To(Tj)
[gteqt]Tcc, resistive heating may be required; evaluate
Equation 4.2.1-2 for all bins.
Case 2. For outdoor bin temperatures where
To(Tj) >Tcc, determine
Qh(Tj) and Eh(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.092
[[Page 58263]]
Note: Even though To(Tj) cc,
additional resistive heating may be required; evaluate Equation
4.2.1-2 for all bins.
4.2.5.2 Heat Pump Having a Heat Comfort Controller: Additional Steps
for Calculating the HSPF of a Heat Pump Having a Single-Speed
Compressor and a Variable-Speed, Variable-Air-Volume-Rate Indoor Blower
Calculate the space heating capacity and electrical power of the
heat pump without the heat comfort controller being active as
specified in section 4.2.2 of this appendix (Equations 4.2.2-1 and
4.2.2-2) for each outdoor bin temperature, Tj, that is
listed in Table 19. Denote these capacities and electrical powers by
using the subscript ``hp'' instead of ``h.'' Calculate the mass flow
rate (expressed in pounds-mass of dry air per hour) and the specific
heat of the indoor air (expressed in Btu/lbmda [middot]
[deg]F) from the results of the H12 test using:
[GRAPHIC] [TIFF OMITTED] TP24AU16.093
where ViS, Vimx, v'n (or
vn), and Wn are defined following Equation 3-
1. For each outdoor bin temperature listed in Table 19, calculate
the nominal temperature of the air leaving the heat pump condenser
coil using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.094
Evaluate eh(Tj)/N, RH(Tj)/N,
X(Tj), PLFj, and [delta](Tj) as
specified in section 4.2.1 of this appendix with the exception of
replacing references to the H1C test and section 3.6.1 of this
appendix with the H1C1 test and section 3.6.2 of this
appendix. For each bin calculation, use the space heating capacity
and electrical power from Case 1 or Case 2, whichever applies.
Case 1. For outdoor bin temperatures where
To(Tj) is equal to or greater than
TCC (the maximum supply temperature determined according
to section 3.1.9 of this appendix), determine
Qh(Tj) and Eh(Tj) as
specified in section 4.2.2 of this appendix (i.e.
Qh(Tj) = Qhp(Tj) and
Eh(Tj) = Ehp(Tj)).
Note: Even though To(Tj) >=TCC,
resistive heating may be required; evaluate Equation 4.2.1-2 for all
bins.
Case 2. For outdoor bin temperatures where
To(Tj) CC, determine
Qh(Tj) and Eh(Tj) using,
Qh(Tj) = Qh(Tj) Eh(Tj) = Ehp(Tj) ECC(Tj)
Where,
[GRAPHIC] [TIFF OMITTED] TP24AU16.095
Note: Even though To(Tj) cc,
additional resistive heating may be required; evaluate Equation
4.2.1-2 for all bins.
4.2.5.3 Heat Pumps Having a Heat Comfort Controller: Additional Steps
for Calculating the HSPF of a Heat Pump Having a Two-Capacity
Compressor
Calculate the space heating capacity and electrical power of the
heat pump without the heat comfort controller being active as
specified in section 4.2.3 of this appendix for both high and low
capacity and at each outdoor bin temperature, Tj, that is
listed in Table 19. Denote these capacities and electrical powers by
using the subscript ``hp'' instead of ``h.'' For the low capacity
case, calculate the mass flow rate (expressed in pounds-mass of dry
air per hour) and the specific heat of the indoor air (expressed in
Btu/lbmda [middot] [deg]F) from the results of the
H11 test using:
[GRAPHIC] [TIFF OMITTED] TP24AU16.096
where Vis, Vimx, v'n (or
vn), and Wn are defined following Equation 3-
1. For each outdoor bin temperature listed in Table 19, calculate
the nominal temperature of the air leaving the heat pump condenser
coil when operating at low capacity using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.097
Repeat the above calculations to determine the mass flow rate
(mda\k=2\) and the specific heat of the indoor air
(Cp,da\k=2\) when operating at high capacity by using the
results of the H12 test. For each outdoor bin temperature
listed in Table 19, calculate the nominal temperature of the air
leaving the heat pump condenser coil when operating at high capacity
using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.098
Evaluate eh(Tj)/N, RH(Tj)/N,
X\k=1\(Tj), and/or X\k=2\(Tj),
PLFj, and [delta]'(Tj) or
[delta]''(Tj) as specified in section 4.2.3.1. 4.2.3.2,
4.2.3.3, or 4.2.3.4 of this appendix, whichever applies, for each
temperature bin. To evaluate these quantities, use the low-capacity
space heating capacity and the low-capacity electrical power from
Case 1 or Case 2, whichever applies; use the high-capacity space
heating capacity and the high-capacity electrical power from Case 3
or Case 4, whichever applies.
Case 1. For outdoor bin temperatures where
To\k=1\(Tj) is equal to or greater than
TCC (the maximum supply temperature determined according
to section 3.1.9 of this appendix), determine
Qh\k=1\(Tj) and
Eh\k=1\(Tj) as specified in section 4.2.3 of
this appendix (i.e., Qh\k=1\(Tj) =
Qhp\k=1\(Tj) and
Eh\k=1\(Tj) =
Ehp\k=1\(Tj).
Note: Even though To\k=1\(Tj)
>=TCC, resistive heating may be required; evaluate
RH(Tj)/N for all bins.
[[Page 58264]]
Case 2. For outdoor bin temperatures where
To\k=1\(Tj) CC, determine
Qh\k=1\(Tj) and
Eh\k=1\(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.099
Note: Even though To\k=1\(Tj)
>=Tcc, additional resistive heating may be required;
evaluate RH(Tj)/N for all bins.
Case 3. For outdoor bin temperatures where
To\k=2\(Tj) is equal to or greater than
TCC, determine Qh\k=2\(Tj) and
Eh\k=2\(Tj) as specified in section 4.2.3 of
this appendix (i.e., Qh\k=2\(Tj) =
Qhp\k=2\(Tj) and
Eh\k=2\(Tj) =
Ehp\k=2\(Tj)).
Note: Even though To\k=2\(Tj)
CC, resistive heating may be required; evaluate
RH(Tj)/N for all bins.
Case 4. For outdoor bin temperatures where
To\k=2\(Tj) CC, determine
Qh\k=2\(Tj) and
Eh\k=2\(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.100
Note: Even though To\k=2\(Tj)
cc, additional resistive heating may be required;
evaluate RH(Tj)/N for all bins.
4.2.5.4 Heat pumps Having a Heat Comfort Controller: Additional
Steps for Calculating the HSPF of a Heat Pump Having a Variable-
Speed Compressor [Reserved]
4.2.6 Additional Steps for Calculating the HSPF of a Heat Pump
Having a Triple-Capacity Compressor
The only triple-capacity heat pumps covered are triple-capacity,
northern heat pumps. For such heat pumps, the calculation of the Eq.
4.2-1 quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.101
differ depending on whether the heat pump would cycle on and off at
low capacity (section 4.2.6.1 of this appendix), cycle on and off at
high capacity (section 4.2.6.2 of this appendix), cycle on and off
at booster capacity (section 4.2.6.3 of this appendix), cycle
between low and high capacity (section 4.2.6.4 of this appendix),
cycle between high and booster capacity (section 4.2.6.5 of this
appendix), operate continuously at low capacity (section 4.2.6.6 of
this appendix), operate continuously at high capacity (section
4.2.6.7 of this appendix), operate continuously at booster capacity
(section 4.2.6.8 of this appendix), or heat solely using resistive
heating (also section 4.2.6.8 of this appendix) in responding to the
building load. As applicable, the manufacturer must supply
information regarding the outdoor temperature range at which each
stage of compressor capacity is active. As an informative example,
data may be submitted in this manner: At the low (k=1) compressor
capacity, the outdoor temperature range of operation is 40 [deg]F <=
T <= 65 [deg]F; At the high (k=2) compressor capacity, the outdoor
temperature range of operation is 20 [deg]F <= T <= 50 [deg]F; At
the booster (k=3) compressor capacity, the outdoor temperature range
of operation is -20 [deg]F <= T <= 30 [deg]F.
a. Evaluate the space heating capacity and electrical power
consumption of the heat pump when operating at low compressor
capacity and outdoor temperature Tj using the equations given in
section 4.2.3 of this appendix for Qh\k=1\(Tj)
and Eh\k=1\ (Tj)) In evaluating the section
4.2.3 equations, Determine Qh\k=1\(62) and
Eh\k=1\(62) from the H01 test,
Qh\k=1\(47) and Eh\k=1\(47) from the
H11 test, and Qh\k=2\(47) and
Eh\k=2\(47) from the H12 test. Calculate all
four quantities as specified in section 3.7 of this appendix. If, in
accordance with section 3.6.6 of this appendix, the H31
test is conducted, calculate Qh\k=1\(17) and
Eh\k=1\(17) as specified in section 3.10 of this appendix
and determine Qh\k=1\(35) and Eh\k=1\(35) as
specified in section 3.6.6 of this appendix.
b. Evaluate the space heating capacity and electrical power
consumption (Qh\k=2\(Tj) and
Eh\k=2\ (Tj)) of the heat pump when operating
at high compressor capacity and outdoor temperature Tj by solving
Equations 4.2.2-3 and 4.2.2-4, respectively, for k=2. Determine
Qh\k=1\(62) and Eh\k=1\(62) from the
H01 test, Qh\k=1\(47) and
Eh\k=1\(47) from the H11 test, and
Qh\k=2\(47) and Eh\k=2\(47) from the
H12 test, evaluated as specified in section 3.7 of this
appendix. Determine the equation input for Qh\k=2\(35)
and Eh\k=2\(35) from the H22,test evaluated as
specified in section 3.9.1 of this appendix. Also, determine
Qh\k=2\(17) and Eh\k=2\(17) from the
H32 test, evaluated as specified in section 3.10 of this
appendix.
c. Evaluate the space heating capacity and electrical power
consumption of the heat pump when operating at booster compressor
capacity and outdoor temperature Tj using
[[Page 58265]]
[GRAPHIC] [TIFF OMITTED] TP24AU16.102
Determine Qh\k=3\(17) and Eh\k=3\(17) from the
H33 test and determine Qh\k=2\(2) and
Eh\k=3\(2) from the H43 test. Calculate all
four quantities as specified in section 3.10 of this appendix.
Determine the equation input for Qh\k=3\(35) and
Eh\k=3\(35) as specified in section 3.6.6 of this
appendix.
4.2.6.1 Steady-state Space Heating Capacity when Operating at
Low Compressor Capacity is Greater than or Equal to the Building
Heating Load at Temperature Tj,
Qh\k=1\(Tj) >=BL(Tj)., and the Heat
Pump Permits Low Compressor Capacity at Tj. Evaluate the
quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.103
using Eqs. 4.2.3-1 and 4.2.3-2, respectively. Determine the equation
inputs X\k=1\(Tj), PLFj, and
[delta]'(Tj) as specified in section 4.2.3.1. In
calculating the part load factor, PLFj, use the low-
capacity cyclic-degradation coefficient CD\h\, [or
equivalently, CD\h\(k=1)] determined in accordance with
section 3.6.6 of this appendix.
4.2.6.2 Heat Pump Only Operates at High (k=2) Compressor
Capacity at Temperature Tj and its Capacity is Greater
than or Equal to the Building Heating Load, BL(Tj)
h\k=2\(Tj). Evaluate the quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.104
as specified in section 4.2.3.3 of this appendix. Determine the
equation inputs X\k=2\(Tj), PLFj, and
[delta]'(Tj) as specified in section 4.2.3.3 of this
appendix. In calculating the part load factor, PLFj, use
the high-capacity cyclic-degradation coefficient,
CD\h\(k=2) determined in accordance with section 3.6.6 of
this appendix.
4.2.6.3 Heat Pump Only Operates at High (k=3) Compressor
Capacity at Temperature Tj and its Capacity is Greater
than or Equal to the Building Heating Load, BL(Tj)
<=Qh\k=3\(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.105
Where:
Xk=3(Tj) = BL(Tj)/Qhk=3(Tj) and PLFj = 1 - ChD(\k=3\) * [1 -
X\k=3\(Tj)]
Determine the low temperature cut-out factor,
[delta]'(Tj), using Eq. 4.2.3-3. Use the booster-capacity
cyclic-degradation coefficient, CD\h\(k=3) determined in
accordance with section 3.6.6 of this appendix.
4.2.6.4 Heat Pump Alternates Between High (k=2) and Low (k=1)
Compressor Capacity to Satisfy the Building Heating Load at a
Temperature Tj, Qh\k=1\(Tj)
j) h\k=2\(Tj). Evaluate the
quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.106
as specified in section 4.2.3.2 of this appendix. Determine the
equation inputs X\k=1\(Tj), X\k=2\(Tj), and
[delta]'(Tj) as specified in section 4.2.3.2 of this
appendix.
4.2.6.5 Heat Pump Alternates Between High (k=2) and Booster
(k=3) Compressor Capacity to Satisfy the Building Heating Load at a
Temperature Tj, Qh\k=2\(Tj)
j) h\k=3\(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.107
[[Page 58266]]
and X\k=3\(Tj) = X\k=2\(Tj) = the heating
mode, booster capacity load factor for temperature bin j,
dimensionless. Determine the low temperature cut-out factor,
[delta]'(Tj), using Eq. 4.2.3-3.
4.2.6.6 Heat Pump Only Operates at Low (k=1) Capacity at
Temperature Tj and its Capacity is less than the Building
Heating Load, BL(Tj) > Qh\k=1\(Tj).
[GRAPHIC] [TIFF OMITTED] TP24AU16.108
where the low temperature cut-out factor, [delta]'(Tj), is
calculated using Eq. 4.2.3-3.
4.2.6.7 Heat Pump Only Operates at High (k = 2) Capacity at
Temperature Tj and its Capacity is less than the Building Heating
Load, BL(Tj) > Qh\k=2\(Tj).
Evaluate the quantities
[GRAPHIC] [TIFF OMITTED] TP24AU16.109
as specified in section 4.2.3.4 of this appendix. Calculate
[delta]''(Tj) using the equation given in section 4.2.3.4 of this
appendix.
4.2.6.8 Heat Pump Only Operates at Booster (k = 3) Capacity at
Temperature Tj and its Capacity is less than the Building Heating
Load, BL(Tj) > Qh\k=3\(Tj) or the
System Converts to using only Resistive Heating.
[GRAPHIC] [TIFF OMITTED] TP24AU16.110
where [delta]''(Tj) is calculated as specified in section 4.2.3.4 of
this appendix if the heat pump is operating at its booster
compressor capacity. If the heat pump system converts to using only
resistive heating at outdoor temperature Tj, set
[delta]'(Tj) equal to zero.
4.2.7 Additional Steps for Calculating the HSPF of a Heat Pump
having a Single Indoor Unit with Multiple Indoor Blowers. The
calculation of the Eq. 4.2-1 quantities
eh(Tj)/N and RH(Tj)/N are evaluated
as specified in the applicable subsection.
4.2.7.1 For Multiple Indoor Blower Heat Pumps that are Connected
to a Singular, Single-speed Outdoor Unit.
a. Calculate the space heating capacity, Qhk=1(Tj),
and electrical power consumption, Ehk=1(Tj), of the heat
pump when operating at the heating minimum air volume rate and
outdoor temperature Tj using Eqs. 4.2.2-3 and 4.2.2-4,
respectively. Use these same equations to calculate the space
heating capacity, Qhk=2(Tj) and electrical power
consumption, Ehk=2(Tj), of the test unit when operating
at the heating full-load air volume rate and outdoor temperature
Tj. In evaluating Eqs. 4.2.2-3 and 4.2.2-4, determine the
quantities Qhk=1(47) and Ehk=1(47) from the
H11 test; determine Qhk=2(47) and
Ehk=2(47) from the H12 test. Evaluate all four
quantities according to section 3.7 of this appendix. Determine the
quantities Qhk=1(35) and Ehk=1(35) as
specified in section 3.6.2 of this appendix. Determine
Qhk=2(35) and Ehk=2(35) from the
H22 frost accumulation test as calculated according to
section 3.9.1 of this appendix. Determine the quantities
Qhk=1(17) and Ehk=1(17) from the
H31 test, and Qhk=2(17) and
Ehk=2(17) from the H32 test. Evaluate all four
quantities according to section 3.10 of this appendix. Refer to
section 3.6.2 and Table 11 of this appendix for additional
information on the referenced laboratory tests.
b. Determine the heating mode cyclic degradation coefficient,
CD\h\, as per sections 3.6.2 and 3.8 to 3.8.1 of this
appendix. Assign this same value to CD\h\(k = 2).
c. Except for using the above values of Qhk=1(Tj),
Ehk=1(Tj), Qhk=2 (Tj), Ehk=2(Tj),
CD\h\, and CD\h\(k = 2), calculate the
quantities eh(Tj)/N as specified in section
4.2.3.1 of this appendix for cases where Qhk=1(Tj) >=
BL(Tj). For all other outdoor bin temperatures,
Tj, calculate eh(Tj)/N and RHh(Tj)/
N as specified in section 4.2.3.3 of this appendix if
Qhk=2(Tj) > BL(Tj) or as specified in section 4.2.3.4 of
this appendix if Qhk=2(Tj) <= BL(Tj).
4.2.7.2 For Multiple Indoor Blower Heat Pumps Connected to
either a Single Outdoor Unit with a Two-capacity Compressor or to
Two Separate but Identical Model Single-speed Outdoor units.
Calculate the quantities eh(Tj)/N and
RH(Tj)/N as specified in section 4.2.3 of this appendix.
4.3 Calculations of Off-Mode Power Consumption
For central air conditioners and heat pumps with a cooling
capacity of:
Less than 36,000 Btu/h, determine the off mode represented value,
PW,OFF, with the following equation:
[GRAPHIC] [TIFF OMITTED] TP24AU16.111
[[Page 58267]]
4.4 Rounding of SEER and HSPF for Reporting Purposes
After calculating SEER according to section 4.1 of this appendix
and HSPF according to section 4.2 of this appendix round the values
off as specified per Sec. 430.23(m) of title 10 of the Code of
Federal Regulations.
[GRAPHIC] [TIFF OMITTED] TP24AU16.112
[[Page 58268]]
Table 20--Representative Cooling and Heating Load Hours for Each
Generalized Climatic Region
------------------------------------------------------------------------
Cooling load Heating load
Climatic region hours CLHR hours HLHR
------------------------------------------------------------------------
I....................................... 2,400 750
II...................................... 1,800 1,250
III..................................... 1,200 1,750
IV...................................... 800 2,250
Rating Values........................... 1,000 2,080
V....................................... 400 2,750
VI...................................... 200 2,750
------------------------------------------------------------------------
4.5 Calculations of the SHR, Which Should Be Computed for Different
Equipment Configurations and Test Conditions Specified in Table 21
Table 21--Applicable Test Conditions for Calculation of the Sensible Heat Ratio
----------------------------------------------------------------------------------------------------------------
Reference
Equipment configuration table number SHR computation with results Computed values
of Appendix M from
----------------------------------------------------------------------------------------------------------------
Units Having a Single-Speed 4 B Test........................ SHR(B).
Compressor and a Fixed-Speed
Indoor blower, a Constant Air
Volume Rate Indoor blower, or
No Indoor blower.
Units Having a Single-Speed 5 B2 and B1 Tests............... SHR(B1), SHR(B2).
Compressor That Meet the
section 3.2.2.1 Indoor Unit
Requirements.
Units Having a Two-Capacity 6 B2 and B1 Tests............... SHR(B1), SHR(B2).
Compressor.
Units Having a Variable-Speed 7 B2 and B1 Tests............... SHR(B1), SHR(B2).
Compressor.
----------------------------------------------------------------------------------------------------------------
The SHR is defined and calculated as follows:
[GRAPHIC] [TIFF OMITTED] TP24AU16.113
Where both the total and sensible cooling capacities are
determined from the same cooling mode test and calculated from data
collected over the same 30-minute data collection interval.
4.6 Calculations of the Energy Efficiency Ratio (EER)
Calculate the energy efficiency ratio using,
[GRAPHIC] [TIFF OMITTED] TP24AU16.114
where Qck(T) and Eck(T) are the space cooling capacity and
electrical power consumption determined from the 30-minute data
collection interval of the same steady-state wet coil cooling mode
test and calculated as specified in section 3.3 of this appendix.
Add the letter identification for each steady-state test as a
subscript (e.g., EERA2) to differentiate among the resulting EER
values.
[FR Doc. 2016-18993 Filed 8-23-16; 8:45 am]
BILLING CODE 6450-01-P
Office of the Federal Register, National Archives and Records Administration
Section
Proposed Rules
Action
Supplemental notice of proposed rulemaking.
Dates
DOE will accept comments, data, and information regarding this supplemental notice of proposed rulemaking (SNOPR) no later than September 23, 2016. See section V, ``Public Participation,'' for details.
Contact
Ashley Armstrong, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, EE-5B, 1000 Independence Avenue SW., Washington, DC 20585-0121. Telephone: (202) 586-6590. Email: [email protected] Johanna Jochum, U.S. Department of Energy, Office of the General Counsel, GC-33, 1000 Independence Avenue SW., Washington, DC 20585- 0121. Telephone: (202) 287-6307. Email: [email protected]
FR Citation
81
FR
58163
RIN Number
1904-AD71
CFR Citation
10
CFR
429 10
CFR
430
CFR Associated
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