81 FR 28588 - Energy Conservation Program for Certain Commercial and Industrial Equipment: Test Procedure for Commercial Water Heating Equipment
DEPARTMENT OF ENERGY
Federal Register Volume 81, Issue 89 (May 9, 2016)
Page Range
28588-28655
FR Document
2016-09539
The U.S. Department of Energy (DOE) proposes to revise its test procedures for commercial water heaters, unfired hot water storage tanks, and hot water supply boilers (henceforth, ``commercial water heating (CWH) equipment'') established under the Energy Policy and Conservation Act of 1975 (EPCA), as amended. In this NOPR, DOE proposes several changes, including: Updating references of industry test standards to incorporate by reference the most recent versions of the industry standards; proposing modifications to the existing test methods for certain classes of CWH equipment; developing new test procedures for determining the efficiency of unfired hot water storage tanks, commercial heat pump water heaters, and flow-activated instantaneous water heaters; proposing clarifications on test set-up and settings for various classes of CWH equipment; revising the certification requirements for CWH equipment; and proposing associated implementing regulations including definitions. DOE announces a public meeting to receive comment on these proposed test procedure amendments, and it also welcomes written comments and data from the public on all aspects of this proposal.
Federal Register, Volume 81 Issue 89 (Monday, May 9, 2016)
[Federal Register Volume 81, Number 89 (Monday, May 9, 2016)]
[Proposed Rules]
[Pages 28588-28655]
From the Federal Register Online [www.thefederalregister.org]
[FR Doc No: 2016-09539]
[[Page 28587]]
Vol. 81
Monday,
No. 89
May 9, 2016
Part III
Department of Energy
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10 CFR Parts 429, 430, and 431
Energy Conservation Program for Certain Commercial and Industrial
Equipment: Test Procedure for Commercial Water Heating Equipment;
Proposed Rule
Federal Register / Vol. 81 , No. 89 / Monday, May 9, 2016 / Proposed
Rules
[[Page 28588]]
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DEPARTMENT OF ENERGY
10 CFR Parts 429, 430, and 431
[Docket No. EERE-2014-BT-TP-0008]
RIN 1904-AD18
Energy Conservation Program for Certain Commercial and Industrial
Equipment: Test Procedure for Commercial Water Heating Equipment
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Notice of proposed rulemaking (NOPR) and announcement of public
meeting.
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SUMMARY: The U.S. Department of Energy (DOE) proposes to revise its
test procedures for commercial water heaters, unfired hot water storage
tanks, and hot water supply boilers (henceforth, ``commercial water
heating (CWH) equipment'') established under the Energy Policy and
Conservation Act of 1975 (EPCA), as amended. In this NOPR, DOE proposes
several changes, including: Updating references of industry test
standards to incorporate by reference the most recent versions of the
industry standards; proposing modifications to the existing test
methods for certain classes of CWH equipment; developing new test
procedures for determining the efficiency of unfired hot water storage
tanks, commercial heat pump water heaters, and flow-activated
instantaneous water heaters; proposing clarifications on test set-up
and settings for various classes of CWH equipment; revising the
certification requirements for CWH equipment; and proposing associated
implementing regulations including definitions. DOE announces a public
meeting to receive comment on these proposed test procedure amendments,
and it also welcomes written comments and data from the public on all
aspects of this proposal.
DATES:
Meeting: DOE will hold a public meeting on June 6, 2016, from 9:30
a.m. to 12:00 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.
Comments: DOE will accept comments, data, and information regarding
this NOPR before and after the public meeting, but no later than July
8, 2016. See section V, ``Public Participation,'' for details.
ADDRESSES: The public meeting will be held at the U.S. Department of
Energy, Forrestal Building, Room 8E-089, 1000 Independence Avenue SW.,
Washington, DC 20585. To attend, please notify Ms. Brenda Edwards at
(202) 586-2945. Further attendance instructions can be found in section
V, ``Public Participation.''
Instructions: All comments submitted must identify the NOPR for
Test Procedures for Commercial Water Heating Equipment, and provide
docket number EERE-2014-BT-TP-0008 and/or regulatory identification
number (RIN) 1904-AD18. Interested persons are encouraged to submit
comments using the Federal eRulemaking Portal at www.regulations.gov.
Follow the instructions for submitting comments. Alternatively,
interested persons may submit comments by any of the following methods:
Email: CommWaterHeatingEquip [email protected].
Include the docket number and/or RIN in the subject line of the
message. Submit electronic comments in WordPerfect, Microsoft Word,
PDF, or ASCII file format, and avoid the use of special characters or
any form of encryption.
Postal Mail: Ms. Brenda Edwards, 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 compact disc (CD), in which case it is not necessary to
include printed copies.
Hand Delivery/Courier: Ms. Brenda Edwards, U.S. Department
of Energy, Building Technologies Office, 950 L'Enfant Plaza SW., Suite
600, Washington, DC 20024. Telephone: (202) 586-2945. If possible,
please submit all items on a CD, in which case it is not necessary to
include printed copies.
DOE will not accept telefacsimilies (faxes). For detailed
instructions on submitting comments and additional information on the
rulemaking process, see section V of this document (Public
Participation).
Docket: The docket is available for review at www.regulations.gov,
including Federal Register notices, public meeting attendee lists and
transcripts, comments, and other supporting documents/materials. All
documents in the docket are listed in the www.regulations.gov index.
However, not all documents listed in the index may be publicly
available, such as information that is exempt from public disclosure.
A link to the docket Web page can be found at: http://www.regulations.gov/#!docketDetail;D=EERE-2014-BT-TP-0008. This Web
page contains a link to the docket for this rulemaking on the
www.regulations.gov site. The www.regulations.gov Web page contains
simple instructions on how to access all documents, including public
comments, in the docket. See section V, ``Public Participation,'' for
further information on how to submit comments through
www.regulations.gov.
For further information on how to submit a comment, review other
public comments and the docket, or participate in the public meeting,
contact Ms. Brenda Edwards at (202) 586-2945 or by email:
[email protected].
FOR FURTHER INFORMATION CONTACT:
Ms. Ashley Armstrong, U.S. Department of Energy, Office of Energy
Efficiency and Renewable Energy, Building Technologies Office, EE-5B,
1000 Independence Avenue SW., Washington, DC 20585-0121. Telephone:
(202) 586-6590. Email: [email protected].
Mr. Eric Stas, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW., Washington, DC 20585-
0121. Telephone: (202) 586-9507. Email: [email protected].
For more information on how to submit a comment, or review other
public comments and the docket, contact Ms. Brenda Edwards, U.S.
Department of Energy, Office of Energy Efficiency and Renewable Energy,
Building Technologies Office, Mailstop EE-5B, 1000 Independence Avenue
SW., Washington, DC 20585-0121. Telephone: (202) 586-2945. Email:
[email protected].
SUPPLEMENTARY INFORMATION: DOE intends to incorporate by reference the
following industry standards into part 431:
(1) Gas Appliance Manufacturers Association (GAMA) Standard IWH-TS-
1, March 2003 edition, ``Method to Determine Performance of Indirect-
Fired Water Heaters,'' sections 4, 5, 6.0, and 6.1;
(2) American National Standards Institute (ANSI) Standard Z21.10.3-
2015/Canadian Standards Association (CSA) Standard 4.3-2015, ``Gas-
fired Water Heaters, Volume III, Storage Water Heaters with Input
Ratings Above 75,000 Btu Per Hour, Circulating and Instantaneous,''
annex E.1;
(3) ANSI/American Society of Heating Refrigeration and Air-
Conditioning Engineers (ASHRAE) Standard 118.1-2012, ``Method of
Testing for Rating Commercial Gas, Electric, and Oil Service Water-
Heating Equipment'';
(4) ASTM International (ASTM) C177-13, ``Standard Test Method for
[[Page 28589]]
Steady-State Heat Flux Measurements and Thermal Transmission Properties
by Means of the Guarded-Hot-Plate Apparatus'';
(5) ASTM C518-10, ``Standard Test Method for Steady-State Thermal
Transmission Properties by Means of the Heat Flow Meter Apparatus;''
and
(6) ASTM D2156-09, ``Standard Test Method for Smoke Density in Flue
Gases from Burning Distillate Fuels.''
Copies of GAMA IWH-TS-1, March 2003 edition, can be obtained from
the Air-conditioning, Heating, and Refrigeration Institute (AHRI), 2111
Wilson Blvd., Suite 500, Arlington, VA 22201, (703) 524-8800, or by
going to http://www.ahrinet.org/App_Content/ahri/files/standards%20pdfs/Indirect-Fired%20Water%20Heater%20Testing%20Standard03.pdf.
Copies of ANSI Z21.10.3-2015/CSA 4.3-2015 and ANSI/ASHRAE 118.1-
2012 can be obtained from the American National Standards Institute, 25
W. 43rd Street, 4th Floor, New York, NY 10036, (212) 642-4800, or by
going to http://webstore.ansi.org/.
Copies of ASTM C177-13, ASTM C518-10, and ASTM D2156-09 can be
obtained from ASTM International, 100 Barr Harbor Drive, P.O. Box C700,
West Conshohocken, PA 19428-2959, (610) 832-9585, or by going to http://www.astm.org/Standard/index.html.
See IV.M. for a further discussion of these standards.
Table of Contents
I. Authority and Background
II. Synopsis of the Notice of Proposed Rulemaking
III. Discussion
A. Updated Industry Test Methods
1. ANSI Z21.10.3 Testing Standard
2. ASTM Standard Test Method D2156
3. ASTM Test Standards C177-13 and C518-10
B. Test Method Repeatability and Ambient Test Conditions
C. Test Method for Unfired Hot Water Storage Tanks
D. Procedure for Setting the Tank Thermostat for Storage and
Storage-Type Instantaneous Water Heaters
E. Clarifications to the Thermal Efficiency and Standby Loss
Test Procedures
F. Definitions for Certain Consumer Water Heaters and Commercial
Water Heating Equipment
1. Consumer Water Heaters
2. Commercial Water Heating Equipment
3. Residential-Duty Commercial Water Heaters
4. Storage-Type Instantaneous Water Heaters
G. Standby Loss Test for Flow-Activated Instantaneous Water
Heaters
H. Test Set Up for Commercial Instantaneous Water Heaters and
Hot Water Supply Boilers
I. Changes to the Standby Loss Test for Instantaneous Water
Heaters and Hot Water Supply Boilers Other Than Flow-Activated
Instantaneous Water Heaters
J. Test Procedure for Rating Commercial Heat Pump Water Heaters
K. Fuel Input Rate
L. Default Values for Certain Test Parameters for Commercial
Water Heating Equipment
M. Certification Requirements
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 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 the 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 Requests To Speak and 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
Title III, Part C \1\ of the Energy Policy and Conservation Act of
1975 (EPCA or the Act), Public Law 94-163 (42 U.S.C. 6311-6317, as
codified), added by Public Law 95-619, Title IV, section 441(a), sets
forth a variety of provisions designed to improve energy efficiency.\2\
It established the ``Energy Conservation Program for Certain Industrial
Equipment,'' a program covering certain commercial and industrial
equipment (hereafter referred to as ``covered equipment''), which
includes the commercial water heating (CWH) equipment that is the
subject of this rulemaking. (42 U.S.C. 6311(1)(K)) Title III, Part B
\3\ of EPCA (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. This includes consumer water heaters, which are also
addressed in this rulemaking. (42 U.S.C. 6292(a)(4))
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\1\ For editorial reasons, Part C was codified as Part A-1 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
(EEIA 2015), Public Law 114-11 (April 30, 2015).
\3\ For editorial reasons, upon codification in the U.S. Code,
Part B was redesignated as Part A.
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Under EPCA, energy conservation programs generally consist of four
parts: (1) Testing; (2) labeling; (3) establishing Federal energy
conservation standards; and (4) certification and enforcement
procedures. The testing requirements consist of test procedures that
manufacturers of covered products and equipment must use as both the
basis for certifying to DOE that their products and equipment comply
with the applicable energy conservation standards adopted pursuant to
EPCA, and for making representations about the efficiency of that
equipment. (42 U.S.C. 6293(c); 42 U.S.C. 6295(s); 42 U.S.C. 6314; 42
U.S.C. 6316)
The initial test procedures for CWH equipment were added to EPCA by
the Energy Policy Act of 1992 (EPACT 1992), Public Law 102-486, and
correspond to those referenced in ASHRAE and Illuminating Engineering
Society of North America (IESNA) Standard 90.1-1989 (i.e., ASHRAE
Standard 90.1-1989) which went into effect on October 24, 1992. (42
U.S.C. 6314(a)(4)(A)) EPCA requires that if an industry test procedure
that is referenced in ASHRAE Standard 90.1 is amended, DOE must amend
its test procedure to be consistent with the amended industry test
procedure, unless DOE determines that the amended test procedure is not
reasonably designed to produce test results that reflect the energy
efficiency, energy use, or estimated operating costs of the equipment
during a representative average use cycle. In addition, DOE must
determine that the amended test procedure is not unduly burdensome to
conduct. (42 U.S.C. 6314(a)(2), (3) and (4)(B))
If DOE determines that a test procedure amendment is warranted, it
must publish a proposed test procedure in the Federal Register and
offer the public an opportunity to present oral and written comments.
(42 U.S.C. 6314(b)(1)-(2)) When amending a test procedure, DOE must
determine to what extent, if any, the proposed test procedure would
alter the equipment's energy efficiency as determined under the
existing test procedure. (42 U.S.C. 6293(e); 42 U.S.C. 6314(a)(4)(C))
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 each type of covered
equipment, including CWH equipment, and either: (1) Amend the test
procedures if the Secretary determines that the amended test procedures
would more accurately or
[[Page 28590]]
fully comply with the requirements of 42 U.S.C. 6314(a)(2)-(3),\4\ or
(2) publish a notice of determination not to amend a test procedure.
(42 U.S.C. 6314(a)(1)(A)) Under this requirement, DOE must review the
test procedures for CWH equipment no later than May 16, 2019, which is
7 years after the most recent final rule amending the Federal test
method for CWH equipment.\5\ The final rule resulting from this
rulemaking will satisfy the requirement to review the test procedure
for CWH equipment within 7 years.
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\4\ 42 U.S.C. 6314(a)(2) requires that test procedures be
reasonably designed to produce test results which reflect energy
efficiency, energy use, and estimated operating costs of a type of
industrial equipment (or class thereof) during a representative
average use cycle (as determined by the Secretary), and not be
unduly burdensome to conduct.
42 U.S.C. 6314(a)(3) requires that if the test procedure is a
procedure for determining estimated annual operating costs, such
procedure must provide that such costs are calculated from
measurements of energy use in a representative average-use cycle (as
determined by the Secretary), and from representative average unit
costs of the energy needed to operate such equipment during such
cycle. The Secretary must provide information to manufacturers of
covered equipment regarding representative average unit costs of
energy.
\5\ DOE published a final rule in the Federal Register on May
16, 2012, that, in relevant part, amended its test procedure for
commercial water-heating equipment. 77 FR 28928.
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DOE's test procedure for CWH equipment is found at 10 CFR 431.106,
Uniform test method for the measurement of energy efficiency of
commercial water heaters and hot water supply boilers (other than
commercial heat pump water heaters).\6\ DOE's test procedure for CWH
equipment provides a method for determining the thermal efficiency and
standby loss of CWH equipment. In a direct final rule for test
procedures for CWH equipment, DOE incorporated by reference certain
sections of the ANSI Standard Z21.10.3-1998 (ANSI Z21.10.3-1998), Gas
Water Heaters, Volume III, Storage Water Heaters With Input Ratings
Above 75,000 Btu Per Hour, Circulating and Instantaneous. 69 FR 61974,
61983 (Oct. 21, 2004). On May 16, 2012, DOE published a final rule for
certain commercial heating, air-conditioning, and water-heating
equipment in the Federal Register that, among other things, updated the
test procedures for certain CWH equipment by incorporating by reference
ANSI Z21.10.3-2011. 77 FR 28928, 28996. These updates did not
materially alter DOE's test procedure for CWH equipment.
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\6\ DOE has reserved a place in its regulations for a test
procedure for commercial heat pump water heaters at 10 CFR 431.107,
Uniform test method for the measurement of energy efficiency for
commercial heat pump water heaters.
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The American Energy Manufacturing Technical Corrections Act
(AEMTCA), Public Law 112-210, was signed into law on December 18, 2012,
and amended EPCA to require that DOE publish a final rule establishing
a uniform efficiency descriptor and accompanying test methods for
consumer water heaters and certain CWH equipment. (42 U.S.C.
6295(e)(5)) AEMTCA required DOE to replace the current efficiency
metric for consumer water heaters (energy factor) and the current
efficiency metrics for commercial water heaters (thermal efficiency and
standby loss) with a uniform efficiency descriptor. (42 U.S.C.
6295(e)(5)(C)) Further, AEMTCA required that the uniform efficiency
descriptor and accompanying test method apply, to the maximum extent
possible, to all water heating technologies currently in use and to
future water heating technologies. (42 U.S.C. 6295(e)(5)(H)) However,
AEMTCA allowed DOE to exclude from the uniform efficiency descriptor,
specific categories of covered water heaters that do not have
residential uses, that can be clearly described, and that are
effectively rated using the current thermal efficiency and standby loss
descriptors. (42 U.S.C. 6295(e)(5)(F))
DOE published a final rule for test procedures for certain CWH
equipment on July 11, 2014 (``July 2014 final rule''). 79 FR 40542. The
final rule modified the current consumer water heater metric (energy
factor) to create uniform energy factor (UEF), the descriptor to be
used as the uniform efficiency descriptor for all consumer water
heaters and certain CWH equipment that have residential uses. Id. at
40544. The final rule excluded certain CWH equipment from the uniform
descriptor equipment that has no residential use, that can be clearly
identified and described, and that are effectively rated using the
current thermal efficiency and standby loss efficiency descriptors. In
the July 2014 final rule, DOE defined and adopted a new test method for
``residential-duty commercial water heaters,'' which are commercial
water heaters that have residential uses. Id.
In this rulemaking for CWH equipment test procedures, DOE only
considers amended test procedures for the CWH equipment classes that do
not have residential applications and that are not ``residential-duty
commercial water heaters'' as adopted in the July 2014 final rule.\7\
On February 27, 2014, DOE published in the Federal Register a request
for information (February 2014 RFI) to seek public comments on several
issues associated with the current test procedure for CWH equipment. 79
FR 10999. DOE accepted comments and information on the February 2014
RFI until March 31, 2014, and considered all feedback received when
developing the proposals contained in this rulemaking. Each of the
issues raised in the February 2014 RFI is discussed in detail in
section III, along with comments received on the issues and DOE's
responses. In addition, several topics not addressed in the February
2014 RFI but brought up by interested parties in their comments are
discussed in section III of this NOPR.
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\7\ Although DOE did not consider amended test procedures for
residential-duty commercial water heaters, DOE proposes to amend the
definitions pertaining to these equipment, as discussed in section
III.F.3.
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In support of its rulemaking effort, DOE typically seeks comments
from the public and uses them to conduct in-depth technical analyses of
publicly-available test standards and other relevant information. As
noted above, this NOPR discusses the comments received by DOE in
response to the February 2014 RFI and summarizes all proposed updates
and amendments to the current test procedure. In its efforts to
continually engage the public and interested parties in the rulemaking
process, DOE seeks data and public input on all aspects of this
rulemaking, in order to improve the testing methodologies, to
accurately reflect commercial use, and to produce repeatable results.
DOE also requests feedback from interested parties and stakeholders on
the proposed amendments to the current test procedures for CWH
equipment.
II. Synopsis of the Notice of Proposed Rulemaking
The February 2014 RFI raised several issues regarding the thermal
efficiency and standby loss test methods for CWH equipment. Several
other issues which were not part of the RFI were brought up through
stakeholder feedback and comments on the RFI. In this NOPR, DOE
discusses all issues identified by DOE and interested parties, and
proposes to modify the current test procedures based on these issues,
as necessary, in order to improve the consistency and accuracy of test
results generated using the DOE test procedure while minimizing test
burden.
As provided in 10 CFR 431.105, the current DOE test procedure
incorporates by reference the ANSI Z21.10.3-2011 test method for use in
10 CFR 431.106, and that latter provision specifically directs one to
follow Exhibits G.1 and
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G.2 of the industry test procedure. In 2013, ANSI updated its test
method and released a more recent version, i.e., ANSI Z21.10.3-2013/
Canadian Standards Association (CSA) 4.3-2013, Gas-fired Water Heaters,
Volume III, Storage Water Heaters with Input Ratings Above 75,000 Btu
Per Hour, Circulating and Instantaneous (hereinafter referred to as
``ANSI Z21.10.3-2013''). In the February 2014 RFI, DOE stated its plan
to amend its test procedure to reference ANSI Z21.10.3-2013, the
updated industry test method for measuring thermal efficiency and
standby loss. 79 FR 10999, 11001-11002 (Feb. 27, 2014). However, since
publication of the February 2014 RFI, ANSI updated its test method
twice. First, an updated version was approved on July 2, 2014, and
released in August 2014, specifically, ANSI Z21.10.3-2014/CSA 4.3-2014,
Gas-fired Water Heaters, Volume III, Storage Water Heaters with Input
Ratings Above 75,000 Btu Per Hour, Circulating and Instantaneous
(hereinafter referred to as ``ANSI Z21.10.3-2014''). Another updated
version was then approved on October 5, 2015, and released in November
2015, specifically, ANSI Z21.10.3-2015/CSA 4.3-2015, Gas-fired Water
Heaters, Volume III, Storage Water Heaters with Input Ratings Above
75,000 Btu Per Hour, Circulating and Instantaneous (hereinafter
referred to as ``ANSI Z21.10.3-2015''). DOE is proposing to incorporate
by reference annexes E.1 of this latest industry test procedure (ANSI
Z21.10.3-2015) for measuring thermal efficiency and standby loss.
After a careful review of ANSI Z21.10.3-2015, DOE found one
significant difference between the sections of the test standard that
are currently referenced by DOE (i.e., Exhibits G.1 and G.2 of ANSI
Z21.10.3-2011) and those contained in ANSI Z21.10.3-2015 (i.e., Annexes
E.1 and E.2). This difference is in the temperature differential terms
used in the equations to calculate standby loss in Annex E.2 of ANSI
Z21.10.3-2015 and Exhibit G.2 of ANSI Z21.10.3-2011. The equations in
Annex E.2 of ANSI Z21.10.3-2015 and Exhibit G.2 of ANSI Z21.10.3-2011
are meant to calculate standby loss, which is defined as the average
hourly energy required to maintain the stored water temperature
expressed as a percentage of the total heat content of the stored water
above room temperature. However, the temperature differential term used
in the denominator of the standby loss equation in Annex E.2 of ANSI
Z21.10.3-2015 does not represent the total heat content of the water
heater. Therefore, DOE has tentatively concluded that it is appropriate
to use the standby loss equation in Exhibit G.2 of ANSI Z21.10.3-2011,
which is both accurate and best represents the standby loss expressed
as a percentage per hour of the total heat content of the stored water
above room temperature. Therefore, DOE proposes to include the equation
for standby loss `S' presented in Exhibit G.2 of ANSI Z21.10.3-2011 in
the DOE test procedure for all covered commercial storage water heaters
and storage-type instantaneous water heaters (see section III.F for
discussion on DOE's proposed definition for ``storage-type
instantaneous water heater''). However, for instantaneous water heaters
and hot water supply boilers other than storage-type instantaneous
water heaters, DOE proposes separate standby loss test procedures and
equations, as discussed in sections III.G and III.I. DOE did not find
any other significant differences between Annexes E.1 and E.2 of ANSI
Z21.10.3-2015 and Exhibits G.1 and G.2 of ANSI Z21.10.3-2011.
Therefore, other than the reference for the standby loss equation, DOE
proposes to update the reference in its test procedures for CWH
equipment (as applicable) to the most recent version of the industry
test standard. Specifically, DOE proposes to incorporate by reference
Annex E.1 of ANSI Z21.10.3-2015. This issue is further discussed in
section III.A of this rulemaking.
DOE's current test procedure for oil-fired CWH equipment at 10 CFR
431.106 also refers to ASTM Standard D2156-80 (``ASTM D2156-80''),
``Standard Test Method for Smoke Density in Flue Gases from Burning
Distillate Fuels.'' Specifically, this industry method is cited to
determine that smoke in the flue does not exceed a No. 1 smoke spot
number. A more recent version of this standard, ASTM Standard D2156-09
(``ASTM D2156-09''), ``Standard Test Method for Smoke Density in Flue
Gases from Burning Distillate Fuels,'' was approved in 2009 and
reapproved in 2013. DOE carefully reviewed the two versions of this
industry method and identified no significant differences that would
affect the determination of smoke spot number as referred to in DOE's
test procedure. Therefore, DOE proposes to incorporate by reference
ASTM D1256-09 for the purpose of determining the smoke spot number.
However, DOE also proposes clarifications to the procedure for
determining the smoke spot number. First, DOE proposes to clarify that
the smoke spot number must be determined prior to taking measurements
for the efficiency tests (i.e., the thermal efficiency test or standby
loss test). Specifically, for the thermal efficiency test, DOE proposes
to require that the smoke spot number be determined after a steady-
state condition has been reached but before beginning measurements for
the thermal efficiency test. For the standby loss test, DOE proposes to
require that the smoke spot number be determined after the first cut-
out before beginning measurements for the standby loss test. However,
DOE proposes not to require that the smoke spot test be conducted prior
to beginning an efficiency test (i.e., thermal efficiency or standby
loss) if no settings on the water heater have been changed and the
water heater has not been turned off since the end of a previously run
efficiency test. DOE also proposes that the requirements for when to
conduct the smoke spot test also apply to measurement of the
CO2 reading, which is required by DOE's current test
procedures for oil-fired CWH equipment at 10 CFR 431.106. Second, DOE
proposes to require that the smoke measuring device be connected to an
open-ended tube that projects into the flue \1/4\ to \1/2\ of the pipe
diameter. This proposed clarification regarding the smoke measuring
device is based on the requirements for commercial space-heating
boilers in the ANSI/AHRI Standard 1500 (``AHRI 1500-2015''), ``2015
Standard for Performance Rating of Commercial Space Heating Boilers.''
Because this requirement comes from an industry-accepted test method,
DOE expects this requirement to lead to minimal test burden for
manufacturers and would simply serve to clarify the test set-up.
DOE's current definition for ``R-value'' at 10 CFR 431.102
references two industry test methods: (1) ASTM Standard Test Method
C177-97 (``ASTM C177-97''), ``Standard Test Method for Steady-State
Heat Flux Measurements and Thermal Transmission Properties by Means of
the Guarded-Hot-Plate Apparatus''; and (2) ASTM Test Standard C518-91
(``ASTM C518-91''), ``Standard Test Method for Steady-State Thermal
Transmission Properties by Means of the Heat Flow Meter Apparatus.''
More recent versions of ASTM C177 and ASTM C518 were published in
October 2013 and June 2010, respectively: (1) ASTM Standard Test Method
C177-13 (``ASTM C177-13''), ``Standard Test Method for Steady-State
Heat Flux Measurements and Thermal Transmission Properties by Means of
the Guarded-Hot-Plate Apparatus''; and (2) ASTM Test
[[Page 28592]]
Standard C518-10 (``ASTM C518-10''), ``Standard Test Method for Steady-
State Thermal Transmission Properties by Means of the Heat Flow Meter
Apparatus.'' After careful review, DOE has tentatively concluded that
there are no substantive differences in the procedures for measuring R-
value between the two versions of ASTM C177 or between the two versions
of ASTM C518. Based upon its analysis, DOE proposes to incorporate by
reference ASTM Standard Test Methods C177-13 and C518-10 and update its
references to these versions in the definition for ``R-value'' at 10
CFR 431.102, in order to maintain up-to-date references to industry
test methods.
Among the comments received by DOE on the published RFI, several
commenters raised concerns with regards to the repeatability of the
standby loss test method as set forth in the current DOE test method
(which references Exhibit G.2 of ANSI Z21.10.3-2011). To address these
concerns of test repeatability, DOE proposes several improvements to
both the thermal efficiency and standby loss test methods, which are
discussed in detail in section III.B of this rulemaking.
Unfired hot water storage tanks are covered equipment included in
the scope of this rulemaking. These tanks store hot water and do not
consume fuel or electricity for the purpose of heating water, so any
energy efficiency improvements would target standby loss associated
with heat loss from the stored water. Currently, unfired hot water
storage tanks are required to have thermal insulation with a minimum
thermal resistance (R-value) of
12.5[emsp14][deg]F[middot]ft\2\[middot]hr/Btu. See 10 CFR 431.110. In
the February 2014 RFI, DOE requested comment on whether the R-value
requirement was an appropriate energy efficiency descriptor and whether
it should adopt a standby loss test and metric to replace the current
R-value requirement. DOE also noted that determining the R-value of a
single sample does not assess whether this value is applicable to the
entire tank surface area, including bottom, top, and fitting areas. 79
FR 10999, 11002 (Feb. 27, 2014). After considering public comments from
stakeholders and interested parties, DOE proposes to adopt a standby
loss test for unfired storage tanks that is based, in part, on existing
industry test methods (i.e., GAMA Testing Standard IWH-TS-1 (March 2003
edition)). Energy conservation standards for unfired hot water storage
tanks will remain in terms of the current insulation R-value
requirement until DOE completes a future rulemaking to establish
standards in terms of the proposed standby loss metric, presuming such
metric is adopted in the test procedure final rule. This proposed
standby loss test method is discussed in detail in section III.C.
Another issue raised by DOE in the February 2014 RFI regarded the
method of setting the tank thermostat prior to conducting the thermal
efficiency test. 79 FR 10999, 11002-03 (Feb. 27, 2014). The current
Federal test procedure at 10 CFR 431.106 references Exhibits G.1 and
G.2 of ANSI Z21.10.3-2011, which requires water heaters to achieve a
maximum mean tank temperature of 140[emsp14][deg]F
5[emsp14][deg]F after the thermostat reduces the gas supply to a
minimum. However, some CWH equipment may experience difficulty in
attaining a mean tank temperature of 140[emsp14][deg]F
5[emsp14][deg]F due to the design of the heat exchanger and positioning
of the thermostat sensor. Such systems may in fact be able to supply
water at a temperature of 140[emsp14][deg]F
5[emsp14][deg]F, but yet not meet the mean tank temperature
requirement. As a result, DOE proposes to modify the test procedure for
gas-fired and oil-fired storage water heaters and storage-type
instantaneous water heaters to use the outlet water temperature as the
set point for setting the thermostat, rather than the mean tank
temperature. This change would still ensure the water heater provides
water at the specified temperature, while accommodating models that are
not designed to have high mean tank temperatures (i.e., condensing
water heaters) or that rely upon stratification. The set point
temperature value would remain the same at 140[emsp14][deg]F 5[emsp14][deg]F. However, for electric storage water heaters,
DOE proposes to maintain a mean tank temperature requirement for the
standby loss test because of complications with setting the thermostats
for each electric heating element. Specifically, it is unclear how each
thermostat could be set to provide a designated outlet water
temperature in a way that would differ from the method used for a mean
tank temperature requirement. Additional discussion of this issue is
contained in section III.D.
In the February 2014 RFI, DOE requested information on whether any
clarifications are needed in the thermal efficiency test procedure to
indicate water flow requirements or to account for changes in thermal
energy stored within the water heater during the duration of the test.
79 FR 10999, 11003 (Feb. 27, 2014). Based on the comments received, DOE
has tentatively concluded that the current test procedure prescribed in
10 CFR 431.106 does not require any amendment to account for changes in
stored thermal energy or water flow requirements during the thermal
efficiency test method. The existing test procedure requires the water
heater to attain steady-state conditions with no variation of outlet
water temperature in excess of 2[emsp14][deg]F over a period of 3
minutes. Once steady-state conditions are achieved, the internal tank
temperature maintains a constant value, indicating that the stored
energy in the water heater remains constant as long as the firing rate
remains constant. While DOE has tentatively concluded that an amendment
to account for stored energy changes is not needed, DOE proposes to
introduce a statement clarifying that during the thermal efficiency
test, the burner must continuously fire at the full firing rate (i.e.,
no modulation or cut-outs) for the entire duration of the thermal
efficiency test, and the outlet water temperature must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature. DOE also proposes to clarify that during the thermal
efficiency and standby loss tests, no settings on the water heating
equipment can be changed until measurements for the test have finished.
Additional discussion of these issues is contained in section III.E.
In this NOPR, DOE proposes several changes to the definitions
included in the regulations for consumer water heaters at 10 CFR 430.2
and for CWH equipment at 10 CFR 431.102. For consumer water heaters,
DOE proposes to remove exemptions from the definitions that exclude
units that heat water to temperatures greater than 180[emsp14][deg]F
and units with a storage capacity greater than 120 gallons. DOE also
proposes to remove the definitions for consumer ``electric heat pump
water heater'' and ``gas-fired heat pump water heater.'' DOE proposes
the following changes to the definitions for CWH equipment: (1)
Replacing all mentions of the terms ``input rating'' or ``rated input''
with the term ``fuel input rate'' in the context of gas-fired or oil-
fired CWH equipment, based on the proposed changes regarding fuel input
rate that are further discussed in section III.K; (2) modifying DOE's
definitions for ``instantaneous water heater'' and ``storage water
heater'' by adding the input criteria that separate consumer water
heaters and commercial water heaters and removing several phrases that
do not serve to clarify coverage of units under the definitions; and
(3) removing the definition of ``packaged boiler.'' DOE also proposes
to modify the definition for ``residential-duty commercial water
heater'' by removing from its scope the following classes, for which
the input criteria indicating
[[Page 28593]]
residential application do not allow classification of any units:
electric storage water heaters, heat pump water heaters with storage,
gas-fired instantaneous water heaters, and oil-fired instantaneous
water heaters. Additional discussion of these proposed changes to DOE's
definitions for consumer water heaters and CWH equipment is provided in
section III.F.
Water heaters with storage tanks and submerged fire-tube heat
exchangers that have input ratings above 4,000 Btu/h per gallon of
water stored are currently classified as instantaneous water heaters
and hot water supply boilers with a storage volume greater than or
equal to 10 gallons. However, DOE believes that these units that are
equipped with storage tanks are fundamentally different from other
instantaneous water heaters, and, therefore, the Department proposes to
define the term ``storage-type instantaneous water heater.'' DOE also
proposes that such units would be tested according to the same method
as used for commercial storage water heaters. Additional discussion of
these issues are contained in section III.F.4.
Instantaneous water heaters and hot water supply boilers are
covered equipment subject to the current Federal test procedure as set
forth in 10 CFR 431.106. In response to the February 2014 RFI, AHRI
raised an issue with regards to the applicability of the standby loss
test procedure described in Exhibit G.2 of ANSI Z21.10.3-2011 for
instantaneous water heaters and hot water supply boilers that have no
means of initiating burner operation without an active flow of water
through the equipment. Additionally, ANSI Z21.10.3-2015 was updated
from previous versions of the industry testing standard to include a
new test method for measuring the standby loss of tube-type
instantaneous water heaters, which AHRI recommended DOE use for
determining the standby loss of such instantaneous water heaters and
hot water supply boilers. DOE identified numerous problematic issues
with this procedure and tentatively decided not to incorporate it by
reference in its test procedures for CWH equipment. (The AHRI comments
and this test method are discussed it in greater detail, along with
DOE's proposed standby loss test procedure for flow-activated
instantaneous water heaters, in section III.G.) The current standby
loss test procedure involves shutting off the flow of water through the
water heater and calculating the amount of energy required to raise the
internally stored water temperature to a thermostatically-set value
when it drops to a point at which it needs to be reheated. For such a
test, it is assumed that when the stored water reaches the minimum
allowable water temperature (below the thermostat set point) a control
signal activates that will initiate the next firing or heating cycle.
This is true for most CWH equipment; however, flow-activated
instantaneous water heaters require flow of water through the heater to
initiate the next firing or heating cycle. In these designs, if there
is no continuous water flow, the next firing or heating cycle is not
triggered even if the temperature of hot water inside the heater falls
below the thermostat set point. To address this issue, DOE proposes to
adopt a separate standby loss test for flow-activated instantaneous
water heaters. DOE currently only prescribes standby loss standards for
gas-fired and oil-fired instantaneous water heater and hot water supply
boilers with a storage capacity greater than or equal to 10 gallons.
The proposed test method would apply to all units that meet the
proposed definition for ``flow-activated instantaneous water heater,''
and is described in detail in section III.G.
The current thermal efficiency and standby loss test method
requires the water heater to be set up as per Figure 2 in ANSI
Z21.10.3-2011, which is identical to Figure 3 in ANSI Z21.10.3-2015.
Although the figures provide an unscaled pictorial arrangement of the
test set up, neither Figure 2 in ANSI Z21.10.3-2011 nor Figure 3 in
ANSI Z21.10.3-2015 specifies the exact location of the outlet water
temperature measurement. DOE understands that this unspecified location
for outlet water temperature measurement could lead to inconsistent
test results and an inaccurate representation of the actual outlet
water temperature, especially if the outlet water temperature
represents the internal stored water temperature for instantaneous
water heaters and hot water supply boilers (as proposed in this NOPR
and discussed in section III.G and III.I). Moreover, the temperature-
sensing installations, as set forth in Annex E.1 of ANSI Z21.10.3-2015,
do not provide clear instructions for installing temperature-sensing
means for instantaneous water heaters and hot water supply boilers.
Considering the issues related to temperature measurement for
instantaneous water heaters and hot water supply boilers, DOE proposes
to specify the temperature-sensing location for the outlet water
temperature such that the tip or junction of the sensor is less than or
equal to 5 inches away from the water heater jacket and requirements
for placement of the temperature-sensing probe in the water line for
both supply and outlet water measurement. In addition to this issue,
DOE also proposes to add supply and outlet water valves at locations
closer to the water heater. Specifically, DOE proposes to add a supply
water valve within a distance of 5 inches from the water heater jacket
and an outlet water valve within a distance of 10 inches from the water
heater jacket. Currently, the test set up does not clearly indicate the
location of the water supply valves. These valves would be turned off
at the start of the standby loss test for instantaneous water heaters
and hot water supply boilers (as proposed in this NOPR and discussed in
section III.G and III.I). DOE also proposes to add provisions for
outlet water temperature measurement and placement of water valves for
instantaneous water heaters and hot water supply boilers that have
multiple supply and outlet water connections and that are shipped with
piping installed by the manufacturer. Finally, DOE proposes to clarify
the conditions for using a re-circulating loop. The proposed provisions
are similar to those specified in ANSI Z21.10.3-2011 (and ANSI
Z21.10.3-2015), and further details on this issue are contained in
section III.H.
In response to the RFI, manufacturers also raised the issue of the
applicability of the current Federal standby loss test procedure to
instantaneous water heaters and hot water supply boilers that are not
tank-type water heaters and that have a storage capacity of ten gallons
or more (all comments on this topic are discussed in section III.I of
this NOPR). The Federal standby loss test procedure in 10 CFR 431.106
incorporates by reference Exhibit G.2 of ANSI Z21.10.3-2011, which
requires the measurement of mean tank temperature to calculate standby
loss. Instantaneous water heaters and hot water supply boilers
generally are not equipped with an integral storage tank, but rather
the stored water is contained within the heat exchanger. Therefore,
measuring the mean tank temperature for such type of equipment would
not be possible (as a storage tank does not exist). Moreover, due to
the complex geometry and design of the heat exchangers of such
equipment, obtaining an accurate value of the mean stored water
temperature inside the heat exchanger would be difficult, or in some
cases, may be impossible. To address this issue, DOE proposes to use
the outlet water temperature as a conservative estimate for the mean
tank temperature. This approach is similar to that used for the standby
loss test for
[[Page 28594]]
flow-activated water heaters and would be significantly less burdensome
than using other means to accurately measure the stored water
temperature inside the heat exchanger. Additional details on this test
procedure are provided in section III.I.
In the February 2014 RFI, DOE also requested comments on
development of a test procedure for commercial heat pump water heaters
(CHPWHs). 79 FR 10999, 11003 (Feb. 27, 2014). Based on the comments
received, DOE proposes to incorporate by reference ANSI/ASHRAE Standard
118.1-2012, Method of Testing for Rating Commercial Gas, Electric, and
Oil Service Water-Heating Equipment (ANSI/ASHRAE Standard 118.1-2012)
to use as the basis for the Federal CHPWH test method, with several
modifications discussed in further detail in III.J. DOE also proposes
to adopt rating conditions for four categories of CHPWHs: (1) Air-
source CHPWHs; (2) direct geo-exchange CHPWHs; (3) ground water-source
CHPWHs; and (4) indoor water-source CHPWHs. The proposed rating
conditions are based on ANSI/AHRI Standard 1300 (I-P)-2013: Performance
Rating of Commercial Heat Pump Water Heaters. Additional discussion of
this proposed test procedure is contained in section III.J.
In its current regulations for CWH equipment in subpart G to 10 CFR
part 431, DOE includes several terms referring to the input capacity,
and does not include any method for determining or verifying the input
capacity during testing. In this NOPR, DOE proposes to define ``fuel
input rate'' for gas-fired and oil-fired CWH equipment and proposes a
procedure for calculating the fuel input rate during the thermal
efficiency test. DOE proposes that the gas consumption be measured
every 10 minutes, and that the calculated fuel input rates for each 10-
minute interval of the thermal efficiency test cannot vary by more than
2 percent between each reading. DOE also proposes means to
verify the fuel input rate. Additional discussion of these proposed
changes regarding fuel input rate is contained in section III.K.
In this NOPR, DOE proposes several changes to its certification
requirements at 10 CFR part 429. First, DOE proposes to add
requirements to 10 CFR 429.44 that manufacturers must certify whether
gas-fired and oil-fired instantaneous water heaters and hot water
supply boilers contain submerged heat exchangers, so that such models
can be classified under DOE's proposed definition for ``storage-type
instantaneous water heaters.'' Second, DOE proposes to require
manufacturers to certify whether instantaneous water heaters and hot
water supply boilers require flow through the water heater to initiate
burner ignition. Further discussion of these proposed changes are
included in section III.M. Additionally, DOE proposes default values
for these parameters to be used in testing if the parameters are not
reported in manufacturer literature shipped with the equipment or the
supplemental test instructions. Further discussion of these proposed
default values are included in section III.L.
In any rulemaking to amend a test procedure, DOE must determine to
what extent, if any, the proposed 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); 42 U.S.C.
6314(a)(4)(C)) DOE expects that the proposed changes to the test
procedure will not significantly alter the efficiency ratings for a
most classes of CWH equipment. There could, however, be changes to the
measured energy efficiency for unfired hot water storage tanks. If DOE
adopts the changes to the existing test procedures proposed in this
NOPR for those products, then DOE will establish energy conservations
standards for unfired hot water storage tanks in terms of a new standby
loss metric in a separate rulemaking, and the test procedure changes
related to unfired hot water storage tanks will not apply until
compliance is required with the new standards. DOE also proposes a new
test procedure for measuring standby loss of flow-activated
instantaneous water heaters with a storage capacity greater than or
equal to 10 gallons. However, DOE does not believe this proposed test
procedure will affect the measured energy efficiency of flow-activated
instantaneous water heaters.
III. Discussion
In response to the February 2014 RFI, DOE received eight written
comments from the following interested parties: Bradford White
Corporation (Bradford White); A.O. Smith Corporation (A.O. Smith); HTP,
Inc. (HTP); Rheem Manufacturing Company (Rheem); Edison Electric
Institute (EEI); Air-Conditioning, Heating, and Refrigeration Institute
(AHRI); American Public Power Association (APPA); and the American
Council for an Energy-Efficient Economy (ACEEE) and National Resources
Defense Council (NRDC), who filed a joint comment (henceforth referred
to as ``Joint Advocates''). These interested parties commented on a
range of issues, including those identified by DOE in the February 2014
RFI, as well as several other pertinent issues. The issues, the
comments received, DOE's responses to those comments, and the resulting
proposed changes to the test procedures for CWH equipment, are
discussed in the following subsections.
Updated Industry Test Methods
DOE's test procedure for measuring the energy efficiency for CWH
equipment currently incorporates by reference the industry standard
ANSI Z21.10.3-2011 at 10 CFR 431.105. Additionally, DOE lists ASTM
Standard Test Methods D2156-80, C177-13, and C518-10 as sources of
information and guidance in 10 CFR 431.104. DOE defines ``ASTM Standard
Test Method D2156-80'' at 10 CFR 431.102, and points to this source in
DOE's current test procedure at 10 CFR 431.106. DOE points to ASTM
C177-13 and ASTM C518-10 in its definition for ``R-value'' at 10 CFR
431.102. The following subsections discuss proposed revisions to DOE's
test procedure for CWH equipment vis-[agrave]-vis these industry
standards.
1. ANSI Z21.10.3 Testing Standard
As noted above, DOE's test procedure for measuring the energy
efficiency for CWH equipment currently incorporates by reference the
industry standard ANSI Z21.10.3-2011 at 10 CFR 431.105. Specifically,
the DOE test procedures at 10 CFR 431.106 directs one to follow
Exhibits G.1 and G.2 of ANSI Z21.10.3-2011 for measuring thermal
efficiency and standby loss, respectively. An updated edition of the
industry test method, ANSI Z21.10.3-2013/CSA 4.3-2013, was approved on
March 25, 2013, and released in July 2013.
In the February 2014 RFI, DOE requested feedback on the
appropriateness of replacing references to ANSI Z21.10.3-2011 with
equivalent references to ANSI Z21.10.3-2013 (which, at that time, was
the most current industry testing standard). 79 FR 10999, 11001-02
(Feb. 27, 2014). All parties that commented on this issue agreed with
DOE that ANSI Z21.10.3-2013 was an appropriate replacement for ANSI
Z21.10.3-2011. (Bradford White, No. 8 at p. 1;\8\ Rheem, No. 3 at p. 1;
HTP, No. 5 at pp. 1-2; A.O. Smith,
[[Page 28595]]
No. 7 at p. 1; Joint Advocates, No. 4 at p. 1; and AHRI, No. 2 at p. 1)
---------------------------------------------------------------------------
\8\ A notation in this form provides a reference for information
that is in the docket of DOE's rulemaking to develop test procedures
for commercial water heating equipment (Docket No. EERE-20014-BT-TP-
0008), which is maintained at www.regulations.gov. This notation
indicates that the statement preceding the reference is document
number 8 in the docket for the test procedure rulemaking for
commercial water heating equipment, and appears at page 1 of that
document.
---------------------------------------------------------------------------
However, since publication of the February 2014 RFI, ANSI updated
its test method twice. First, an updated version was approved on July
2, 2014, and released in August 2014--ANSI Z21.10.3-2014/Canadian
Standards Association (CSA) 4.3-2014, Gas-fired Water Heaters, Volume
III, Storage Water Heaters with Input Ratings Above 75,000 Btu Per
Hour, Circulating and Instantaneous (hereinafter referred to as ``ANSI
Z21.10.3-2014''). Another updated version was then approved on October
5, 2015, and released in November 2015--ANSI Z21.10.3-2015/CSA 4.3-
2015, Gas-fired Water Heaters, Volume III, Storage Water Heaters with
Input Ratings Above 75,000 Btu Per Hour, Circulating and Instantaneous
(hereinafter referred to as ``ANSI Z21.10.3-2015''). DOE reviewed ANSI
Z21.10.3-2015 and compared it with ANSI Z21.10.3-2011, and found one
significant difference between the sections of the test method that DOE
currently references in its test procedures for CWH equipment (i.e.,
Exhibits G.1 and G.2 of ANSI Z21.10.3-2011) and those contained in ANSI
Z21.10.3-2015 (i.e., Annexes E.1 and E.2). In Exhibit G.2 of ANSI
Z21.10.3-2011, the current DOE test procedure, the equation for standby
loss `S' is presented as:
[GRAPHIC] [TIFF OMITTED] TP09MY16.267
In Annex E.2 of ANSI Z21.10.3-2015, the equation is exactly the
same, except that the [Delta]3term in the denominator of the
second term of the equation is replaced by [Delta]T4. Based
on the definitions for the terms provided in both ANSI Z21.10.3-2011
and ANSI Z21.10.3-2015, [Delta]T3 refers to the difference
between the average value of the mean tank temperature and the average
value of the ambient room temperature expressed in [deg]F. The term
[Delta]T4 is defined as the difference between the final and
the initial mean tank temperature.
DOE has tentatively concluded that the standby loss equation
provided in ANSI Z21.10.3-2011 (and ANSI Z21.10.3-2013) is appropriate.
If the [Delta]T3 term is replaced with the
[Delta]T4 term in the second term of the standby loss
equation as specified by ANSI Z21.10.3-2015, then the term
[Delta]T4 would cancel out, and the equation will not
include the temperature difference between the final and initial mean
tank temperature that corresponds to the heat lost by the water heater
during the course of the test. Therefore, DOE proposes to adopt as part
of appendices A and B to subpart G of part 431 the standby loss
equation as specified in Exhibit G.2 of ANSI Z21.10.3-2011 (and also
included in ANSI Z21.10.3-2013) for calculating the standby loss of all
storage water heaters and storage-type instantaneous water heaters. DOE
also proposes to re-arrange the terms of the equation to improve the
readability of the equation, and remove the gas consumption term for
electric water heaters. For instantaneous water heaters and hot water
supply boilers other than storage-type instantaneous water heaters, DOE
proposes separate standby loss test procedures and equations in
sections III.G and III.I.
DOE did not find any other substantive differences between Exhibits
G.1 and G.2 of ANSI Z21.10.3-2011 and Annexes E.1 and E.2 of ANSI
Z21.10.3-2015. Therefore, DOE proposes to incorporate by reference
Annex E.1 of ANSI Z21.10.3-2015 in its proposed test procedures for CWH
equipment. DOE does not propose to incorporate by reference Annex E.2
of ANSI Z21.10.3-2015; however, DOE has included certain language from
Annex E.2 in its standby loss test procedures proposed in this NOPR.
ANSI Z21.10.3-2015 also includes a new efficiency test procedure--
Annex E.3, ``Method of test for measuring standby loss for tube type
instantaneous water heaters with 10 or greater gallons of storage.''
This procedure provides a method to test standby loss of instantaneous
water heaters and hot water supply boilers, including those that
require flow of water to activate the burner or heating element (i.e.,
``flow-activated instantaneous water heaters''). DOE reviewed this test
procedure, and it is discussed in further detail in section III.G,
where DOE proposes a new standby loss test procedure for flow-activated
instantaneous water heaters.
DOE also proposes a procedure similar to that specified in section
5.27 of ANSI Z21.10.3-2015 for determining the storage volume of CWH
equipment. DOE's proposed language only includes clarifying differences
from the language in section 5.27 of ANSI Z21.10.3-2015, and DOE
believes that the clarifying differences would not affect conduct of
the test procedure between DOE's proposed procedure and the method
included in section 5.27 of ANSI Z21.10.3-2015. DOE's proposed
procedure for determining storage volume is discussed in further detail
in section III.G.
2. ASTM Standard Test Method D2156
DOE's current test procedure for oil-fired CWH equipment at 10 CFR
431.106 points to ASTM Standard Test Method D2156-80. Specifically, DOE
requires that smoke in the flue does not exceed No. 1 smoke as measured
by the procedure in ASTM D2156-80. However, there is a more recent
version of ASTM D2156 that was approved on December 1, 2009, and
reapproved on October 1, 2013. After careful review of D2156-80 and
D2156-09, DOE has tentatively concluded that no substantive changes
were made between these versions in the test method for determining the
smoke spot number. Therefore, DOE proposes to incorporate by reference
this newer version, ASTM D2156-09, in its test procedures for oil-fired
CWH equipment, in appendices A, C, and E to subpart G of 10 CFR part
431.
DOE's current requirement for smoke spot number of flue gas for
oil-fired CWH equipment requires that the smoke in the flue does not
exceed No. 1 smoke, but does not specify when during the test to
determine the smoke spot number. To improve consistency and
repeatability of testing of CWH equipment, DOE is proposing to specify
when to conduct the smoke spot test. DOE considered several options for
this specification. The first option DOE considered would be to require
determination of the smoke spot number after steady-state operation has
been achieved, but prior to beginning measurement for the thermal
efficiency test. The second option considered would be to require
determination of the smoke spot number before and after conduct of the
test. The third option considered would be to require determination of
the smoke spot number before, after, and during the test. Specifically,
in the third option, the
[[Page 28596]]
smoke spot number would be determined during the thermal efficiency
test 15 minutes after the beginning of the test. This is similar to the
requirement to determine the smoke spot number every 15 minutes during
the thermal efficiency and combustion efficiency tests that is
specified for commercial space heating boilers in AHRI 1500-2015.
After considering these three options and the relative benefits and
test burden they might provide, DOE has tentatively concluded that
determining the smoke spot number prior to conduct of efficiency
testing sufficiently assesses the combustion performance while
minimizing test burden for manufacturers. DOE reasoned that it is
unlikely for the smoke density to change to a significant extent during
a steady-state test if the burner settings are maintained throughout
the test. As discussed in section III.E, DOE is also proposing to add a
clarifying statement to the test procedure stating that the settings on
CWH equipment during the thermal efficiency test are not be changed
once steady-state conditions have been established. Therefore, DOE has
tentatively concluded that it is not necessary to require determination
of the smoke spot number during or after efficiency testing, and rather
proposes to require determination of the smoke spot number before
beginning measurement for efficiency testing. Specifically, for the
thermal efficiency test, DOE proposes to require determination of the
smoke spot number after steady-state condition has been reached (as
determined by no variation of outlet water temperature in excess of
2[emsp14][deg]F over a 3-minute period). For the standby loss test, DOE
proposes to require determination of the smoke spot number after the
first cut-out before beginning measurements for the standby loss test.
DOE also proposes to require that the CO2 reading, which is
required to be measured when testing oil-fired CWH equipment under
DOE's current test procedures specified at 10 CFR 431.106, also be
measured at the time required for determination of the smoke spot
number.
DOE also proposes to clarify that the smoke spot test and
measurement of CO2 reading are required before conduct of
the thermal efficiency test or standby loss test (as applicable) of
oil-fired CWH equipment with one exception. DOE proposes that, if no
settings on the water heater have been changed and the water heater has
not been turned off since the end of a previously run efficiency test,
a second smoke spot test or CO2 reading is not required
prior to beginning another efficiency test (i.e., thermal efficiency or
standby loss).
Additionally, to further clarify the appropriate method for
determining the smoke spot number, DOE proposes to adopt specifications
to the test procedure for the set-up for measuring the smoke density.
Specifically, DOE proposes to require that the smoke measuring device
be connected to an open-ended tube, and that this tube must project
into the flue \1/4\ to \1/2\ of the pipe diameter. These proposed
requirements are from the same as those specified for commercial space-
heating boilers in AHRI 1500-2015.
Issue 1: DOE seeks comment on its proposed incorporation by
reference of ASTM D2156-09, and on its proposed additional
specifications for how to set up the smoke spot test, and when to
conduct the smoke spot test and measure the CO2 reading.
3. ASTM Test Standards C177-13 and C518-10
DOE's current definition for ``R-value'' at 10 CFR 431.102
references two industry test methods: ASTM Standard Test Method C177-97
and ASTM Test Standard Method C518-91.
A more recent version of ASTM C177 was approved in September 2013
and published in October 2013 (ASTM C177-13). After careful review, DOE
has tentatively concluded that there are no substantive differences in
the procedures for measuring R-value between the two versions of ASTM
C177. Additionally, a more recent version of ASTM C518 was approved in
May 2010 and published in June 2010 (ASTM C518-10). After careful
review, DOE has tentatively concluded that there are no substantive
differences in the procedures for measuring R-value between the two
versions of ASTM C518. Therefore, DOE proposes to incorporate by
reference ASTM Standard Test Methods C177-13 and C518-10 and to update
its references to these versions in the definition for ``R-value'' at
10 CFR 431.102.
Issue 2: DOE seeks comment on its proposed incorporation by
reference of ASTM C177-13 and C518-10 for the definition of ``R-
value.''
B. Test Method Repeatability and Ambient Test Conditions
As discussed in section III.A of this rulemaking, the DOE test
procedure for CWH equipment currently incorporates by reference ANSI
Z21.10.3-2011 at 10 CFR 431.105, and DOE proposes to incorporate by
reference Annex E.1 of the updated version of the standard, ANSI
Z21.10.3-2015, for measuring thermal efficiency and standby loss,
respectively.
The test method for thermal efficiency of CWH equipment in Annex
E.1 of ANSI Z21.10.3-2015 (and also in Exhibit G.1 of ANSI Z21.10.3-
2011) requires that the thermostat be set so that the gas supply is
reduced to a minimum, once the mean tank temperature reaches
140[emsp14][deg]F 5[emsp14][deg]F. Then water is supplied
continuously to the water heater at a temperature of 70[emsp14][deg]F
2[emsp14][deg]F. The outlet water temperature is adjusted
by varying the flow rate until the temperature is constant at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature. After the outlet water reaches steady state, water flow
(measured by weight) is recorded for a 30-minute test period, along
with supply and outlet water temperatures, the ambient room
temperature, and fuel and electricity consumption. These data collected
during the 30-minute test period are used to calculate the thermal
efficiency.
The standby loss test method in Annex E.2 of ANSI Z21.10.3-2015
(and also in Exhibit G.2 of ANSI Z21.10.3-2011) stipulates that a
commercial water heater must be set up as described for the thermal
efficiency test and that the unit must be put into operation with the
burner gas supply opened. After the first burner cut-out,\9\ the unit
is allowed to remain in standby mode until the second burner cut-out,
at which point the collection of test data begins. Test data are
recorded at 15 minute intervals, and the test ends at either the first
cut-out after 24 hours have elapsed, or when 48 hours have elapsed,
whichever occurs first. The ambient room temperature, mean tank
temperature, fuel and electricity consumption, and time are measured
during the test and used to calculate the standby loss.
---------------------------------------------------------------------------
\9\ By ``burner cut-out,'' DOE refers to when the energy supply
to a burner is reduced to a minimum.
---------------------------------------------------------------------------
In the February 2014 RFI, DOE requested information and data
pertaining to the repeatability of thermal efficiency and standby loss
test methods included in the ANSI Z21.10.3-2011 and ANSI Z21.10.3-2013
test methods. 79 FR 10999, 11001-02 (Feb. 27, 2014).
HTP commented that the thermal efficiency test is repeatable and is
reasonably consistent between testing sites. (HTP, No. 5 at p. 2) No
other interested parties provided information on the repeatability of
the thermal efficiency test method in ANSI Z21.10.3.
Several parties provided comments regarding the repeatability of
the standby loss test method. HTP commented that the standby loss test
[[Page 28597]]
method produces data with significant lab-to-lab variation in test
results and attributed this variation to the physics of the test and
the ambient conditions of the test. HTP suggested investigating the
effects of stipulating a maximum air draft in the test environment on
repeatability of the standby loss test. (HTP, No. 5 at p. 2) HTP and
AHRI commented that due to the small amount of energy consumption
measured during the standby loss test, the error and variation
associated with the tolerances of commercially-available test
instrumentation has a larger influence on test results, resulting in a
greater degree of variance for the standby loss test compared to the
thermal efficiency test. (HTP, No. 5 at p. 2 and AHRI, No. 2 at p. 1)
Based on these comments from interested parties, DOE investigated
various potential test procedure modifications to reduce the
variability of results from the test procedures for thermal efficiency
and standby loss. In addition, DOE conducted investigative testing that
helped inform the proposals discussed in this NOPR. DOE proposes the
following seven modifications to the current thermal efficiency and
standby loss test procedures, after tentatively determining that these
modifications would reduce variation in results: (1) Stipulating a
maximum air draft requirement of 50 ft/min as measured prior to
beginning the thermal efficiency or standby loss tests; (2) tightening
the ambient room temperature tolerance from 10.0[emsp14][deg]F to 5.0[emsp14][deg]F and the
allowed variance from mean ambient temperature from 7.0[emsp14][deg]F to 2.0[emsp14][deg]F; (3) requiring
measurement of test air temperature--the temperature of entering
combustion air--and requiring the test air temperature not vary by more
than 5[emsp14][deg]F from the ambient room temperature at
any measurement interval during the thermal efficiency and standby loss
tests for gas-fired and oil-fired CWH equipment; (4) establishing a
requirement for ambient relative humidity of 60 percent 5
percent during the thermal efficiency and standby loss tests for gas-
fired and oil-fired CWH equipment; (5) requiring a soak-in period prior
to testing in which the water heater must sit without any draws taking
place for at least 12 hours from the end of a recovery from a cold
start; (6) specifying the locations of inlet and outlet temperature
measurements for storage water heaters, storage-type instantaneous
water heaters, and UFHWSTs; and (7) decreasing the time interval for
data collection from fifteen minutes to 30 seconds in the thermal
efficiency and standby loss tests. While manufacturers cited concerns
regarding only the repeatability of the standby loss test in response
to comments to the February 2014 RFI, DOE has tentatively concluded
that the following proposed modifications would improve the
repeatability of both tests. Unless otherwise specified in the
following paragraphs, DOE proposes that these changes would apply to
thermal efficiency and standby loss tests for all CWH equipment (as
applicable).
(1) Addition of a maximum air draft stipulation, as recommended by
HTP. This modification would allow for more consistent ambient
conditions between tests and testing locations, as well as limit the
effect of air draft on testing results. DOE proposes to add a
requirement that while conducting the thermal efficiency and standby
loss tests and during the proposed soak-in period (as applicable), a
water heater must be protected from drafts of more than 50 ft/min from
room ventilation registers, windows, or other external sources of air
movement, to be measured within three feet of the jacket of the water
heater. This requirement is similar to the requirement adopted for
testing consumer water heaters and certain commercial water heaters in
the July 2014 final rule. 79 FR 40542, 40569 (July 11, 2014). DOE notes
that Annex E.1 of ANSI Z21.10.3-2015 requires that water heater
placement in the test room shall be protected from drafts. This
modification simply clarifies the meaning of ``protected from drafts''
by setting a requirement for the maximum allowable draft during the
test. DOE proposes that the air draft be measured prior to beginning
the soak-in period and thermal efficiency and standby loss tests, and
that no actions can be taken during the conduct of the tests or the
soak-in period that would increase the air draft near the water heater
being tested.
(2) A decrease in the allowed maximum variance for ambient room
temperature for both the thermal efficiency and standby loss tests. The
current test procedure at 10 CFR 431.106 references Exhibits G.1 and
G.2 of ANSI Z21.10.3-2011, which require that the ambient room
temperature be maintained at 75[emsp14][deg]F
10[emsp14][deg]F, and that the ambient room temperature not vary by
more than 7[emsp14][deg]F from the average ambient room
temperature during the test. DOE proposes requiring that the ambient
room temperature be maintained at 75[emsp14][deg]F
5[emsp14][deg]F and that the room temperature not vary by more than
2.0[emsp14][deg]F from the average ambient room temperature
while setting thermostats and verifying steady-state operation, between
the first and second cut-outs prior to the standby loss test (as
applicable), and during the thermal efficiency and standby loss tests
and proposed soak-in period (as applicable) for all CWH equipment.
(3) Addition of a requirement for measurement of test air
temperature for gas-fired and oil-fired commercial water heating
equipment. DOE understands that the entering air temperature can have a
significant impact on combustion in gas-fired and oil-fired CWH
equipment. To improve repeatability of the thermal efficiency and
standby loss tests for these classes of equipment, DOE proposes to
require measurement of test air temperature, within 2 feet of the air
inlet to the water heater. For CWH equipment that does not have a
specific air inlet, DOE proposes that the test air temperature be
measured within 2 feet of the jacket of the water heater closest to
where air would be drawn for combustion. DOE also proposes a
requirement that the test air temperature may not vary by more than
5[emsp14][deg]F from the ambient room temperature at any
measurement interval during the course of the thermal efficiency or
standby loss tests (as applicable) or while establishing steady-state
operation prior to the thermal efficiency test for gas-fired and oil-
fired CWH equipment. For units with multiple air inlets, DOE proposes
that the test air temperature must be measured at each air inlet, and
that the specified tolerance on deviation from the ambient room
temperature must be maintained at each air inlet. This required
tolerance for test air temperature was modeled after AHRI 1500-2015 in
order to remain consistent with common industry practices. However, DOE
proposes that this test air temperature requirement not apply to the
standby loss test for flow-activated instantaneous water heaters
proposed in section III.G of this NOPR, because the burner will not
activate during the test. DOE also does not propose a test air
temperature requirement for electric water heaters because electric
water heaters are not powered by combustion, and, therefore, the test
air temperature does not affect the efficiency of the heating elements.
(4) Establishment of a requirement for ambient relative humidity of
60 percent 5 percent for gas-fired and oil-fired
commercial water heating equipment. DOE understands that humidity can
have a significant effect on the tested efficiency of gas-fired and
oil-fired CWH equipment, particularly condensing equipment. High
humidity would enable equipment to capture more latent heat from
combustion gases, thereby resulting in a higher measured
[[Page 28598]]
efficiency. Therefore, the lack of a specification for ambient humidity
in DOE's current test procedures for gas-fired and oil-fired CWH
equipment can lead to variation in test results between test labs. DOE
recognizes that this effect would be noticeable in tests for both
thermal efficiency and standby loss. Therefore, DOE proposes to amend
its test procedures by specifying a requirement that ambient relative
humidity be set and maintained at 60 percent 5 percent for
gas-fired and oil-fired CWH equipment while verifying steady-state
operation and during the thermal efficiency and standby loss tests, so
as to minimize this effect, which should reduce variability in test
results. However, DOE proposes that this ambient humidity requirement
not apply to the standby loss test for flow-activated instantaneous
water heaters proposed in section III.G of this NOPR, because the
burner will not activate during the test. DOE also does not propose an
ambient humidity requirement for electric water heaters because
electric water heaters are not powered by combustion and, therefore,
the ambient air humidity does not affect the efficiency of the heating
elements. Also, DOE proposes that the ambient relative humidity be
measured and recorded at the same location as the test air temperature,
and at 30-second intervals during the entire test. For units with
multiple air inlets, DOE proposes that the ambient relative humidity
must be measured at each air inlet, and that 60 percent 5
percent must be maintained at each air inlet. DOE proposes that the
ambient relative humidity must remain within the specified range at all
times during conduct of the thermal efficiency and standby loss tests.
(5) Addition of a requirement to perform a pre-test conditioning
phase, also known as a soak-in period, for storage water heaters and
storage-type instantaneous water heaters. This proposed provision would
require that the water heater remain idle (i.e., no water draws) for at
least 12 hours with the thermostats maintained at settings that would
achieve the required water temperature (see section III.D for further
detail on proposed requirements for setting the tank thermostat), prior
to conducting either a thermal efficiency test or standby loss test.
This modification is similar to the soak-in period requirement adopted
for consumer water heaters and certain commercial water heaters in the
July 2014 final rule. 79 FR 40542, 40571 (July 11, 2014). This
requirement would help minimize transient heat transfer effects that
may reduce the reproducibility of the current standby loss test.
However, DOE proposes not to require a soak-in period be conducted
prior to beginning an efficiency test (i.e., thermal efficiency or
standby loss) if no settings on the water heater have been changed and
the water heater has not been turned off since the end of a previously
run efficiency test. DOE proposes a requirement for a soak-in period
for unfired hot water storage tanks with different test conditions in
section III.C.
(6) Specifying the locations for inlet and outlet water temperature
measurement for storage water heaters, storage-type instantaneous water
heaters, and unfired hot water storage tanks. DOE's current test
procedure for CWH equipment incorporates by reference the requirement
in Exhibit G.1 of ANSI Z21.10.3-2011 that the inlet and outlet piping
be immediately turned vertically downward from the connections on a
tank-type water heater to form heat traps and that the thermocouples
for measuring inlet and outlet water temperatures be installed before
the inlet heat trap piping and after the outlet heat trap piping. While
DOE agrees with the general position of the inlet and outlet
thermocouples relative to the heat trap piping, the precise location of
the thermocouples in terms of distance away from the water heater is
not specified. The absence of a clearly defined location for the
thermocouples can contribute to variability in the test results.
Considering this issue, DOE proposes that the thermocouples be placed
with total vertical piping length of 24 inches. For water heaters with
vertical connections, the 24 inches of total vertical piping distance
is divided into 6 inches of vertical piping upstream from the turn for
the heat trap and 18 inches downstream from the turn for the heat trap.
For water heaters that have horizontal water connections, DOE proposes
that the thermocouples be placed with total horizontal piping length
between the thermocouple location and the connection port of six
inches. For water heaters that have vertical water connections, due to
the differences in the size and dimensions of water heaters, it may not
be possible to have the inlet and outlet water piping be turned
vertically downward after a fixed horizontal distance of 6 inches away
from the connection port. Therefore, for water heaters with vertical
connections (opening top or bottom), DOE proposes that the horizontal
distance be equal to the distance from the connection port to the edge
of the water heater plus 2 inches. Figure III.1, Figure III.2, and
Figure III.3 show the three proposed configurations for placement of
inlet and outlet water thermocouples for tank-type water heaters. All
dimensions shown in the figures and specified in this paragraph are
measured from the outer surface of the pipes or water heater jacket (as
applicable).
BILLING CODE 6450-01-P
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[GRAPHIC] [TIFF OMITTED] TP09MY16.268
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[GRAPHIC] [TIFF OMITTED] TP09MY16.269
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(7) Increasing the frequency of data collection. To further reduce
variability in test results, DOE proposes to decrease the length of the
time interval between data collection during the thermal efficiency
test from 1 minute to 30 seconds and during the standby loss test from
15 minutes to 30 seconds for all CWH equipment (as applicable). This
time interval would apply to the measurement of ambient room
temperature, test air temperature, and ambient relative humidity for
both the thermal efficiency and standby loss tests (as applicable). For
the thermal efficiency test, the 30-second time interval would also
apply to the measurement of supply and outlet water temperatures. For
the standby loss test the 30-second time interval would apply to the
measurement of mean tank temperature for storage and storage-type
instantaneous water heaters (storage-type instantaneous water heaters
are discussed in section III.F), and to measurement of outlet water
temperature for instantaneous water heaters and hot water supply
boilers. Additionally, DOE proposes that the fuel (i.e., gas or oil)
consumption be measured at 10-minute intervals during the thermal
efficiency test. These increases in frequency of data collection would
increase data granularity, thereby providing more information to
identify testing irregularities contributing to test result variance.
This modification would also allow for more accurate timing of test
start and stop, which may lead to more repeatable results.
DOE also considered three other modifications to improve standby
loss test repeatability, but ultimately decided against proposing these
modifications for the reasons provided. The three additional considered
but rejected modifications include:
(1) An increase in the number of temperature sensors measuring
internal tank temperature from six to twelve. These sensors would be
located at the vertical midpoint of 12 equal volumes of water within
the water heater. It was thought that this modification could
potentially increase the reliability of the internal tank temperature
data and allow better resolution of temperature stratification within
the tank. However, based on preliminary test data, DOE observed that
increasing the number of sensors had little effect on the outcome of
the test and, thus, does not justify the additional burden.
(2) An increase in the number of thermal probes used to measure
ambient temperature from one to at least four. These probes could be
located at the vertical midpoint of the tank at a perpendicular
distance of 24 inches (61 cm) from the surface of the jacket, and in
each cardinal direction (i.e., North, South, East, and West). It was
thought that this modification could potentially help reduce
uncertainty of the true ambient temperature profile around the water
heater and the associated effect of this uncertainty on the measured
standby loss of tested CWH equipment. However, based on preliminary
test data, DOE observed that increasing the number of sensors had
little effect on the ambient temperature readings, and, thus, little
impact on the outcome of the test. Consequently, it would not justify
the additional burden.
(3) Lengthening the required period for establishing steady-state
operation prior to the thermal efficiency test to thirty minutes. DOE's
current test procedure references Exhibit G.1 of ANSI Z21.10.3-2011,
which requires that the outlet water temperature be established as
constant prior to conducting the thermal efficiency test, as determined
by no variation in excess of 2[emsp14][deg]F over a 3-minute period.
For some equipment, a 3-minute period may not be long enough to
establish steady-state operation of gas-fired or oil-fired CWH
equipment, and a water heater could conceivably exhibit no variation in
excess of 2[emsp14][deg]F over a 3-minute period before establishing
steady-state operation. Additionally, DOE notes that the current test
procedure does not impose requirements for maximum variation in inlet
water temperature or water flow rate during this period for verifying
steady-state operation. Thus, DOE believes that extending the period
for determining steady-state operation could improve test method
repeatability, and DOE is seeking information and data regarding such a
change. DOE notes that for commercial packaged boilers, which are
similar equipment to some classes of CWH equipment, AHRI 1500-2015
specifies a 30-minute warm-up period for determining steady-state
operation has been achieved.
Issue 3: DOE requests comments and data on its proposed changes to
improve the repeatability of the thermal efficiency and standby loss
test procedures for certain commercial water heating equipment.
Specifically, DOE requests comment on its proposed requirements for
ambient relative humidity. DOE does not propose this requirement for
testing of electric water heaters, and seeks feedback on whether
including such a requirement would improve the repeatability of the
standby loss test for electric water heaters. DOE is also seeking
comments regarding any additional changes that would improve the
repeatability of the thermal efficiency and standby loss tests.
Issue 4: DOE requests comment on the changes to improve test
repeatability for its test procedures for certain CWH equipment that
were identified but not proposed in this NOPR. If comments suggest that
DOE should implement these changes, then DOE will evaluate whether it
can adopt those changes in the final rule or must engage in further
rulemaking. Particularly, DOE requests data showing what duration for
the steady-state verification period would ensure steady-state
operation is reached for gas-fired and oil-fired CWH equipment prior to
the thermal efficiency test. DOE also seeks data that suggest suitable
tolerances for water temperature and flow rate for this steady-state
verification period. Additionally, DOE seeks comment on whether
different requirements for establishing steady-state operation are
warranted for each equipment class of CWH equipment.
C. Test Method for Unfired Hot Water Storage Tanks
EPCA defines an ``unfired hot water storage tank'' (UFHWST) as a
tank used to store water that is heated externally. (42 U.S.C.
6311(12)(C)) The current Federal standard for this equipment type
requires a minimum thermal insulation (R-value) of 12.5. 10 CFR
431.110. DOE defines ``R-value'' as the thermal resistance of
insulating material as determined based on ASTM Standard Test Method
C177-97 or ASTM Standard Test Method C518-91 and expressed in
[deg]F[middot]ft\2\[middot]h/Btu. 10 CFR 431.102. In section III.A.3 of
this rulemaking, DOE proposes to update references to these standards
in its definition for ``R-value'' by incorporating by reference ASTM
C177-13 and ASTM C518-10.
DOE is aware that some manufacturers ship UFHWSTs without
insulation, and that uninsulated UFHWSTs may or may not then be
insulated on-site. In this rulemaking, DOE makes clear that UFHWSTs
shipped without insulation are not compliant with the Federal R-value
standard. All UFHWSTs must either be shipped insulated to the R-value
standard or shipped together with insulation meeting the R-value
standard. Manufacturers of UFHWSTs must certify that the insulation
meets the R-value standard prescribed in 10 CFR 431.110, and this
certification must be based on testing according to the methods
prescribed in the R-value definition. A UFHWST manufacturer may
demonstrate compliance with the insulation requirements either by
[[Page 28602]]
conducting testing itself or by using test data from the insulation
material producer. Further, manufacturers of UFHWSTs are responsible
for retaining records of the underlying test data used for
certification in accordance with current maintenance of records
requirements set forth at 10 CFR 429.71.
Because DOE includes ASTM test methods for measuring R-value in its
definition of ``R-value,'' DOE does not currently specify a test
procedure for measuring energy efficiency of UFHWSTs in 10 CFR 431.106.
In the February 2014 RFI, DOE requested comment on whether the R-value
is an adequate energy efficiency descriptor for UFHWSTs. DOE also
requested comment on the potential for replacing R-value with standby
loss, or another metric, as the energy efficiency descriptor for
UFHWSTs, and how to establish a standby loss test or other test for
this equipment if such a metric is appropriate. 79 FR 10999, 11002
(Feb. 27, 2014).
A.O. Smith, AHRI, and Rheem commented that there is no need for a
test procedure to measure the R-value of the insulation on UFHWSTs.
(A.O. Smith, No. 7 at pp. 1-2; AHRI, No. 2 at pp. 2-3; Rheem, No. 3 at
pp. 1-2) AHRI also commented that the R-value requirement is in no way
a measurement of the ``efficiency'' of an unfired storage tank, and
that ASHRAE deliberately did not include a thermal efficiency or
standby loss requirement for this equipment in ASHRAE Standard 90.1.
(AHRI, No. 2 at pp. 2-3) Bradford White and HTP support the current
requirement of a minimum insulation R-value, and Bradford White
estimated that replacing the R-value metric with a metric requiring an
efficiency test would require 3 days of testing per model. (Bradford
White, No. 8 at p. 1; HTP, No. 5 at p. 2) AHRI, HTP, and Rheem also
expressed support for the current two ASTM test methods (C177-97 and
C518-91) for testing the R-value of insulation for UFHWSTs. (AHRI, No.
2 at pp. 2-3; HTP, No. 5 at p. 2; Rheem, No. 3 at pp. 1-2)
Joint Advocates noted that the two ASTM test methods are intended
for flat samples, while UFHWSTs are generally pressure vessels with
curved surfaces. (Joint Advocates, No. 4 at p. 2) Joint Advocates
recommended replacing the present R-value requirement for UFHWSTs with
a standby loss test similar to the test used for electric and fuel-
fired commercial water heaters because the current R-value requirement
does not ensure that all surfaces of the tank are adequately insulated,
nor does it encourage other methods to reduce heat loss, such as anti-
siphon connections and/or eliminating thermal bridges. Joint Advocates
also recommended that for any units with legitimate needs for field
insulation of UFWHSTs, DOE could either allow for a waiver or establish
a separate class of uninsulated UFHWSTs. (Joint Advocates, No. 4 at p.
2)
A.O. Smith and AHRI also pointed out that there exists a group of
UFHWSTs that are larger than standard volume models and are often built
to order. (A.O. Smith, No. 7 at p. 2; AHRI, No. 2 at pp. 2-3) A.O.
Smith and AHRI stated that these units are often shipped without
insulation and subsequently field-insulated due to shipping and
installation considerations that make it impractical to insulate at the
site of manufacture. (A.O. Smith, No. 7 at p. 2; AHRI No. 2 at pp. 2-3)
After considering these comments, DOE has tentatively determined
that a measurement of energy efficiency of UFHWSTs is necessary to more
fully comply with the requirements of 42 U.S.C. 6314(a)(2)-(3), and
proposes a standby loss metric and test method to replace the current
R-value requirement. Although DOE recognizes that requiring use of a
standby loss test will increase test burden for manufacturers, DOE has
tentatively concluded that the benefits of such a metric would outweigh
this additional burden. Primarily, DOE agrees with Joint Advocates that
a standby loss metric would encourage and credit energy-saving
technologies that are not measured by the R-value of the insulation and
ensure that all surfaces are adequately insulated. As a result, DOE
proposes to establish a standby loss test method for UFHWSTs that
monitors the decrease in tank temperature from a set temperature. In
addition, DOE proposes to amend the definition of ``standby loss'' at
10 CFR 431.102 to include unfired hot water storage tanks.
Regarding the points from AHRI, A.O. Smith, and Joint Advocates
about UFHWSTs that are shipped without insulation and subsequently
field-insulated, DOE reiterates that all UFHWSTs must have a minimum
thermal insulation R-value of 12.5 when they are shipped from the
manufacturer. Any units shipped without a minimum thermal insulation of
R-12.5 and then insulated on-site would not be compliant with DOE's
current regulations.
To determine the standby loss of an UFHWST, the storage capacity of
the tank must first be determined. Section 5.27 of ANSI Z21.10.3-2015
includes a method for measuring the storage capacity, and it states
that this method is applicable to water heaters including storage
vessels. DOE examined this method and found no reason why it would be
inapplicable to UFHWSTs. Therefore, DOE proposes to use the test method
described in section 5.27 of ANSI Z21.10.3-2015 to measure the storage
capacity of UFHWSTs. DOE includes a procedure for determining storage
volume in its proposed test procedure for UFHWSTs that has only
clarifying differences from the method presented in section 5.27 of
ANSI Z21.10.3-2015. DOE's proposed procedure for determining storage
volume is discussed in further detail in section III.G.
Next, DOE considered three possible test methods to determine the
standby loss coefficient and hourly standby losses of an UFHWST. The
first method considered--and the one that DOE proposes as the test
method for UFHWSTs--is based on a method for assessing the energy
efficiency of indirect water heaters, which was originally developed by
the GAMA,\10\ and set forth in Testing Standard IWH-TS-1, ``Method to
Determine Performance of Indirect-Fired Water Heaters'' (March 2003
edition).\11\ Under this procedure, the tank is set up as would
normally be done in the field, with potable water inlet and outlet
piping and supply and return piping connected to an external heat
source. This procedure specifies bringing the water in the tank to a
mean temperature of 140[emsp14][deg]F by the external heat source, and
then monitoring the stored water temperature while the heat source is
inactive and the water temperature inside the tank decreases. A linear
fit is applied to temperature data as the mean tank temperature drops
from 137[emsp14][deg]F to 133[emsp14][deg]F to yield a temperature
decay term with units of [deg]F/h. DOE proposes to use this test method
as the basis of a test method to determine the standby loss of UFHWSTs
but with several modifications. DOE has tentatively concluded that the
use of Testing Standard IWH-TS-1 would sufficiently capture the heat
loss of UFHWSTs and reduce burden to manufacturers relative to
alternative methods, because it is already an industry-accepted
procedure that is used in AHRI's certification program for indirect
water heaters.
---------------------------------------------------------------------------
\10\ The Air-Conditioning and Refrigeration Institute (ARI) and
GAMA merged to become AHRI on January 1, 2008.
\11\ Available at: http://www.org/App_Content/ahri/files/standards%20pdfs/Indirect-Fired%20Water%20Heater%20Testing%20Standard03.pdf (last accessed
February 12, 2015).
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As noted in this preamble, DOE proposes several modifications to
Testing Standard IWH-TS-1 to be included in DOE's proposed test
[[Page 28603]]
procedure for standby loss of UFHWSTs. First, because the nominal tank
temperature for determining standby loss for commercial storage water
heaters is 140[emsp14][deg]F, DOE proposes to calculate standby loss of
UFHWSTs using temperature data collected as the mean tank temperature
drops from 142[emsp14][deg]F to 138[emsp14][deg]F instead of
137[emsp14][deg]F to 133[emsp14][deg]F. To do so, DOE proposes that the
tank be filled with water that is heated sufficiently to achieve a mean
tank temperature of 145[emsp14][deg]F and then be allowed to decrease
from that point. Consequently, DOE also proposes to update the water
density and specific heat capacity constants used in calculation of
standby loss to 8.205 lb/gallon and 0.999 Btu/[deg]F[middot]lb
respectively, to correspond to the mid-point of DOE's proposed
temperature range (140[emsp14][deg]F), instead of the mid-point of the
temperature range specified in Testing Standard IWH-TS-1
(135[emsp14][deg]F). However, DOE notes that the value for specific
heat capacity of water does not change as the temperature increases
from 135[emsp14][deg]F to 140[emsp14][deg]F, with the number of
significant figures specified in Testing Standard IWH-TS-1.
DOE also proposes to adopt the same ambient room temperature
requirement for all CWH equipment that is discussed in section III.B.
Specifically, DOE proposes that the ambient room temperature must be
maintained at 75[emsp14][deg]F 5[emsp14][deg]F during the
test (as measured at each 30-second interval), and the measured room
temperature must not vary by more than 2.0[emsp14][deg]F
from the average ambient room temperature during the test. While
Testing Standard IWH-TS-1 specifies an ambient room temperature of
70[emsp14][deg]F, DOE notes that many manufacturers of UFHWSTs also
manufacture storage water heaters. Therefore, DOE expects that
manufacturer burden would be reduced if storage water heaters and
UFHWSTs can be tested in the same test room, and DOE's proposal is
consistent with that objective. Additionally, DOE proposes a
requirement for maximum air draft in section III.B that applies to the
soak-in period and standby loss test for UFHWSTs. Similar to ambient
room temperature, DOE expects that aligning this requirement with that
for other classes of CWH equipment will reduce testing burden for CWH
manufacturers. DOE also proposes a requirement for a soak-in period to
be conducted prior to beginning the standby loss test for UFHWSTs. In
this soak-in period, the tank must sit without any draws taking place
for at least 12 hours after being filled with water such that a mean
tank temperature of 145[emsp14][deg]F 5[emsp14][deg]F is
achieved. After completion of the soak-in period, DOE would require
that the UFHWST be filled again such that a mean tank temperature of
145[emsp14][deg]F 5[emsp14][deg]F is achieved, because the
stored water temperature would decrease during the soak-in period.
Additionally, DOE proposes requirements for piping insulation and water
supply similar to those for other classes of CWH equipment included in
Annex E.1 of ANSI Z21.10.3-2015.
DOE also proposes to collect temperature data at intervals of 30
seconds during this test, as opposed to the 15-minute intervals
specified by the IWH-TS-1 test method. DOE has determined that a higher
number of data points will improve the accuracy of the least-squares
regression and that, given the data storage capacity of modern data
acquisition equipment, the higher frequency of data collection will
pose only a negligible additional burden upon laboratories, as compared
to the current 15-minute data collection interval. DOE also proposes to
convert the decay rate metric to the standby loss metric currently
applied to commercial storage water heaters, which has units of Btu/h.
DOE also considered two other approaches to determine the standby
loss for UFHWSTs and is presenting these alternatives as part of this
NOPR for comment on their merits compared to the proposed method. The
first alternative is similar to the method proposed, but uses a
different condition to end the standby loss test. Specifically, under
this approach, the test would end 24 hours after the beginning of the
test, instead of after the mean tank temperature reaches a specified
temperature. However, the use of such a test ending condition would
result in different final water temperatures for units with different
rates of heat loss. This variation in final water temperature would
impart an undesirable benefit to UFHWSTs that lose heat more quickly,
because the rate of heat transfer from water to the surrounding air
decreases as the corresponding temperature difference decreases.
Additionally, DOE believes that a change in test ending condition to a
24-hour time limit may result in unnecessary test burden for
manufacturers, as it would likely extend the duration of the test. In
light of the potential downsides to this alternative, DOE has
tentatively concluded that the test method proposed in this document
(based on the industry-accepted IWH-TS-1 test method) would
sufficiently capture the rate of heat loss from the tank while
potentially allowing for a shorter test time.
DOE also considered a second alternative test method that would
maintain the set point of the hot water within the UFHWST, by
connecting an UFHWST to an external heat source (i.e., a water heater
or boiler) that would replace water in the tank that has cooled down
with water that has been heated by the external source. Circulation
from the external heat source to the water heater would be controlled
based on the internal tank temperature. The amount of water circulated
into the UFHWST from the external source and the temperature of supply
water and return water would be monitored during reheat cycles to
determine the amount of energy supplied to the tank. This test would
start one hour after a reheat cycle and would progress until one hour
after completion of the first reheat cycle after 24 hours have elapsed
since the start of the test. Calculation of standby loss would include
the change in stored energy within the UFHWST, as well as energy
supplied to the UFHWST by the external heat source. While this test
method would more closely align with DOE's standby loss test procedures
for electric and fuel-fired CWH equipment and be more representative of
field use of UFHWSTs, DOE has tentatively concluded that this method
would be overly burdensome to manufacturers and could lead to increased
variability in test results. Use of other CWH equipment to heat water
being supplied to the UFHWST could lead to variability based on
variation in the equipment and piping used for testing. Based on
preliminary test data, DOE observed similar results for a method that
uses circulation with an external heat source and a method that does
not; therefore, DOE has tentatively concluded that a method using
circulation with an external heat source would not provide a more
accurate result that would be commensurate with the additional testing
burden of such an approach.
Issue 5: DOE requests comment on the proposed test procedure to
determine the standby loss for UFHWSTs, and on whether any other
methods, including those detailed in this NOPR, would lead to a better
test. Specifically, DOE solicits feedback on whether the proposed test
would be long enough to determine an accurate standby loss rating,
whether the use of a linear approximation of the temperature decay is
sufficient to estimate the standby loss, whether running the test by
simply letting the temperature decay (rather than providing external
heat to bring the temperature of the water back to operational
temperature) is appropriate, and whether the adoption of test
[[Page 28604]]
conditions (i.e., ambient room temperature, maximum air draft, water
temperature) similar to that of other classes of CWH equipment is
appropriate. DOE also seeks comment on whether any of its identified
alternatives could be modified to improve their repeatability and to
decrease test burden, thereby supporting further consideration.
D. Procedure for Setting the Tank Thermostat for Storage and Storage-
Type Instantaneous Water Heaters
DOE's test method for measuring the energy efficiency of CWH
equipment currently requires that the thermostat be set to achieve
specific conditions for the mean tank temperature before the test may
begin. In particular, section g of Exhibit G.1 of ANSI Z21.10.3-2011
(which is currently incorporated by reference into the DOE test
procedure) requires that before starting testing, the thermostat
setting must be adjusted such that, when starting with the water in the
system at 70[emsp14][deg]F 2[emsp14][deg]F, the maximum
mean tank temperature will be 140[emsp14][deg]F
5[emsp14][deg]F after the thermostat reduces the gas supply to a
minimum. DOE understands that some units may have difficulty achieving
the required mean tank temperature condition, and in the February 2014
RFI DOE requested feedback on potential test procedure amendments to
address this issue. 79 FR 10999, 11003 (Feb. 27, 2014).
In response to the February 2014 RFI, the four manufacturers among
the interested parties (A.O. Smith, Bradford White, HTP, and Rheem), as
well as AHRI, expressed support for changing the set point conditions
to require monitoring the outlet water temperature rather than the mean
tank temperature. (Bradford White, No. 8 at p. 1; Rheem, No. 3 at p. 2;
HTP, No. 5 at p. 2; A.O. Smith, No. 7 at p. 2; AHRI, No. 2 at p. 4)
A.O. Smith, Rheem, and AHRI expressed support for maintaining the set
point condition at 140[emsp14][deg]F 5[emsp14][deg]F for
the outlet water temperature. (A.O. Smith, No. 7 at p. 2; Rheem, No. 3
at p. 2; AHRI, No. 2 at p. 4) A.O. Smith stated that certain designs of
CWH equipment cannot reach a mean tank temperature of 140[emsp14][deg]F
5[emsp14][deg]F, including down-fired, condensing
equipment with reduced firing rates, and solar or other renewable
source equipment. (A.O. Smith, No. 7 at p. 2) DOE received no comments
opposing a potential change from setting the thermostat based on the
mean tank temperature to setting the thermostat based on the
temperature of the delivered water.
After carefully considering these comments, DOE proposes to modify
the thermal efficiency and standby loss test procedures for gas-fired
and oil-fired storage water heaters and storage-type instantaneous
water heaters to require that before starting testing, the thermostat
setting be adjusted such that, when starting with the water in the
system at 70 [deg]F 2 [deg]F, the maximum outlet water
temperature will be 140 [deg]F 5 [deg]F after the
thermostat reduces the gas supply to a minimum. DOE has tentatively
concluded that changing from a mean tank temperature requirement to an
outlet temperature requirement would better accommodate designs of gas-
fired and oil-fired water heaters that are not designed to have high
mean tank temperatures (e.g., condensing water heaters) or that rely
upon stratification.
DOE does not propose changing the mean tank temperature requirement
to an outlet water temperature requirement for electric storage water
heaters because of complications with setting tank thermostats.
Electric storage water heaters have multiple heating elements and a
thermostat corresponding to each element, and each thermostat needs to
be set prior to beginning the standby loss test. Therefore, DOE reasons
that electric storage water heaters, which vary in configuration and
number of heating elements, are not well-suited to an outlet water
temperature requirement because it is unclear how the lower thermostats
would be set to achieve a designated outlet water temperature. A
consistent, reproducible process for setting the thermostats is
essential to having a repeatable test. Therefore, DOE proposes to
maintain a mean tank temperature requirement for the standby loss test
for electric storage water heaters. However, DOE proposes to clarify
its language specifying the method for setting thermostats in an
electric storage water heater with multiple thermostats. Specifically,
DOE proposes to clarify that the thermostats are to be set in immediate
succession, starting from the topmost thermostat. DOE also proposes to
clarify that when setting each thermostat, the mean tank temperature is
calculated using only temperature readings measured at locations higher
in the tank than the heating element corresponding to the thermostat
being set, with the exception of the bottommost thermostat. Finally,
DOE proposes to clarify that all thermostats below the thermostat being
tested must be turned off so that no elements below the thermostat
being tested are in operation.
Issue 6: DOE seeks comment on its proposed change to its
requirements for setting the tank thermostat in the thermal efficiency
and standby loss test procedures for gas-fired and oil-fired storage
and storage-type instantaneous water heaters from measurement of mean
tank temperature to measurement of outlet water temperature.
Issue 7: DOE seeks comment on its tentative decision to maintain a
mean tank temperature requirement for the standby loss test for
electric storage water heaters. DOE also requests comment on its
clarifying language for setting tank thermostats for electric storage
water heaters with multiple thermostats.
E. Clarifications to the Thermal Efficiency and Standby Loss Test
Procedures
The calculation of thermal efficiency included in the current DOE
test procedure for gas-fired and oil-fired CWH equipment at 10 CFR
431.106 (which incorporates the method used in Exhibit G.1 of ANSI
Z21.10.3-2011) does not consider change in internal stored energy of
the stored water.\12\ In the February 2014 RFI, DOE sought public
comment on whether it is necessary to account for the potential
variation in stored thermal energy inside the water heater during the
course of the test, and specifically whether there is a need to account
for losses in the internal stored energy in the thermal efficiency
calculation. 79 FR 10999, 11003 (Feb. 27, 2014). In addition, DOE
sought feedback on whether there is need for clarification to ensure
that the water flow rate is adjusted so that the burner is fired at a
constant firing rate or whether cycling of the burner is allowed. Id.
---------------------------------------------------------------------------
\12\ The thermal efficiency test procedure in Exhibit G.1. of
ANSI Z21.10.3-2011 is a steady-state procedure where the supply
water temperature is maintained at 70[emsp14][deg]F
2[emsp14][deg]F, outlet water temperature is maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature, and the flow rate is adjusted to a constant value that
can maintain these temperatures throughout the duration of the test.
Because the supply and outlet water temperatures and the water flow
rate are not varied while taking the measurements to calculate the
thermal efficiency, rate of change of stored energy in the water
heater would be zero.
---------------------------------------------------------------------------
In response, DOE received several comments from interested parties
and stakeholders. AHRI commented that no change is required to the test
procedure to address this issue. According to AHRI, the intent of the
test method is that the burner be operated at a continuous, full-input
firing rate, and once steady state is achieved, there would not be any
issue with regards to potential changes in stored heat within the water
heater. (AHRI, No. 2 at p. 4) Rheem deferred to AHRI's comments of not
requiring any change in the thermal efficiency test method. (Rheem, No.
3 at p. 2) Bradford White, HTP, and A.O.
[[Page 28605]]
Smith also commented on this issue. Bradford White did not see any
merit in modifying the test procedure to account for variation in
thermal energy stored in the tank. As a possible clarification,
Bradford White suggested adding a sentence stating that, ``flow rate
must achieve continuous full rate burner operation at the required
stable outlet water temperature.'' According to Bradford White, stored
energy would only be a significant consideration if the test conditions
are not allowed to stabilize sufficiently or if the conditions are not
controlled tightly. Bradford White recommended additional investigation
of any modification that is proposed if DOE decides to amend the test
procedure to account for stored energy changes. (Bradford White, No. 8
at pp. 1-2) A.O. Smith commented that the current test procedure for
determining thermal efficiency has been used for a very long time
without any confusion, and accordingly, A.O. Smith did not recommend
any changes in the current test procedure. (A.O. Smith, No. 7 at p. 2)
HTP commented that units are commonly pre-conditioned before the test,
and recommended requiring products be pre-conditioned as part of the
DOE test method. Further, HTP asserted that if tanks are pre-
conditioned, it would not expect any additional accuracy achieved by
accounting for the difference in energy maintained within the storage
tank during the test. (HTP, No. 5 at p. 3) Joint Advocates encouraged
any changes that would minimize systematic errors if the current test
procedure is insufficiently specific and if an agreement can be reached
on a reasonable method whose cost is commensurate to the value of the
change. (Joint Advocates, No. 4 at p. 2)
DOE considered all comments received from interested parties in
response to this issue. Based on the comments received, DOE has
tentatively decided not to implement any changes in the current thermal
efficiency test methods or calculations for CWH equipment to account
for changes in thermal energy stored in the water heater during the
course of the 30-minute test. However, DOE proposes to clarify the
requirements for maintaining steady-state operation throughout the
thermal efficiency test. Specifically, DOE proposes to clarify that no
settings on the water heater may be changed during the course of the
thermal efficiency test, once steady-state operation is achieved, as
determined by no variation of outlet water temperature in excess of
2[emsp14][deg]F over a 3-minute period. This includes setting the flow
rate during testing such that the heater operates at full firing rate
(i.e., no modulation or cut-outs) for the entire duration of the test.
Although the current test method is clear in requiring the test
conditions to reach steady state prior to starting the test, there
could be some confusion on whether these conditions are required to be
maintained for the entire duration of the test. DOE proposes to add a
statement to clarify steady-state operation during the thermal
efficiency test. The proposed clarifying statement specifies that the
test entity must maintain the outlet water temperature at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature and ensure the burner fires continuously at the full firing
rate (i.e., no modulation or cut-outs) for the entire duration of the
thermal efficiency test. Further, the proposed statement clarifies that
once steady-state operation is achieved, as determined by no variation
of the outlet water temperature in excess of 2[emsp14][deg]F over a 3-
minute period, no settings on the water heating equipment may be
changed until measurements for the thermal efficiency test are
finished.
Additionally, DOE proposes to clarify a similar requirement for the
standby loss test for CWH equipment other than those meeting DOE's
proposed definition for ``flow-activated instantaneous water heater.''
DOE proposes to require that after the first cut-out before beginning
the standby loss test, no settings may be changed on the water heating
equipment until measurements for the standby loss test are finished.
Issue 8: DOE requests comment on its proposed clarifying statements
regarding steady-state operation and manipulation of CWH equipment
settings during efficiency tests.
F. Definitions for Certain Consumer Water Heaters and Commercial Water
Heating Equipment
1. Consumer Water Heaters
EPCA's definition of water heater specifies input ratings at or
below which water heaters are to be classified as consumer water
heaters (e.g., 75,000 Btu/h for gas-fired storage water heaters; 12 kW
for electric storage water heaters and electric instantaneous water
heaters; 210,000 Btu/h for oil-fired instantaneous water heaters). (42
U.S.C. 6291(27)) DOE's regulatory definition of ``water heater''
restates the definition from the consumer products part of EPCA. (42
U.S.C. 6291(27); 10 CFR 430.2) In addition to adopting EPCA's
definition of water heater, DOE had defined a variety of terms that
helped specify the test procedure provisions that applied to specific
kinds of water heaters. See, e.g., 10 CFR part 430, subpart B, appendix
E, in the 10 CFR parts 200 to 499 edition, revised as of January 1,
2015 (defining, for example, gas instantaneous water heater and
electric storage-type water heater). These test procedure definitions
included provisions related to water temperature design characteristics
and rated storage volume. The standards at 10 CFR 430.32 and the water
heater definition at 10 CFR 430.2 did not include any such limitations.
In the July 11, 2014 test procedure final rule, in an effort to
consolidate all relevant definitions in 10 CFR 430.2, DOE removed the
definitions for specific kinds of consumer water heaters from its test
method at appendix E to subpart B of part 430 and added definitions to
10 CFR 430.2 (i.e., ``Electric heat pump water heater,'' ``Electric
instantaneous water heater,'' ``Electric storage water heater,'' ``Gas-
fired heat pump water heater,'' ``Gas-fired instantaneous water
heater,'' ``Gas-fired storage water heater,'' ``Oil-fired instantaneous
water heater,'' and ``Oil-fired storage water heater''). 79 FR 40542,
40549, 40566-67 (July 11, 2014). These definitions became effective on
July 13, 2015, and excluded products with a rated storage capacity
greater than 120 gallons and in some cases included limitations with
respect to units designed to heat and store water at a thermostatically
controlled temperature less than or equal to 180[emsp14][deg]F. 79 FR
40542, 40566-67 (July 11, 2014). These changes to the definitions were
proposed and finalized after the publication of the April 16, 2010
final rule setting amended standards for consumer water heaters, and
they were not effective until after the April 16, 2015 compliance date
for those standards. As noted previously, the standards and definition
set forth in EPCA do not include any requirement related to the water
temperature or storage capacity. Therefore, prior to the effectiveness
of July 2014 regulation, any product meeting the definition of a
``water heater'' would have been subject to the statutory standards
applicable to consumer water heaters, regardless of the water delivery
temperature or storage capacity.
DOE now proposes to correct the definitions for specific types of
consumer water heaters included at 10 CFR 430.2 by removing from the
definitions the specifications related to the water temperature and
storage capacity. Thus, a model that would otherwise meet the
definition of a consumer water heater does not ``become'' commercial as
the result of the unit's capability of producing water
[[Page 28606]]
at temperatures above 180[emsp14][deg]F. More generally, a product that
utilizes gas, oil, or electricity to heat potable water for use outside
the heater upon demand that does not meet the statutory definition of
``water heater'' at 42 U.S.C. 6291(27) as implemented by this proposed
rule, if adopted, would be a commercial water heater, subject to the
standards for such water heaters as set forth in 42 U.S.C. 6313.
Furthermore, DOE notes that, if a manufacturer offers a product
that meets the definition of a water heater at 10 CFR 430.2, but cannot
be tested by the applicable test procedure, the manufacturer should
notify DOE and request a waiver from the applicable test method using
the procedures at 10 CFR 430.27. If a waiver were granted, DOE would
update its test procedure in the next rulemaking for consumer water
heaters. DOE does not anticipate, however, that such a waiver would be
needed. The UEF test procedure was developed quite recently and was
designed to span the consumer product/commercial equipment boundary;
accordingly, DOE expects that all units (irrespective of designed water
temperature and/or rated storage capacity) can be tested without
difficulty.
In its definitions at 10 CFR 430.2, DOE currently defines the terms
``electric heat pump water heater'' and ``gas-fired heat pump water
heater.'' In its energy conservation standards for consumer water
heaters at 10 CFR 430.32(d), DOE does not use the terms ``electric heat
pump water heater'' or ``gas-fired heat pump water heater.'' DOE's
Uniform Test Method for Measuring the Energy Consumption of Water
Heaters at appendix E to subpart B of part 430 also does not use these
terms. Therefore, DOE proposes to remove these terms.
As discussed in the previous paragraphs, DOE proposes to revise the
definitions for ``Electric instantaneous water heater'', ``Electric
storage water heater'', ``Gas-fired instantaneous water heater'',
``Gas-fired storage water heater'', ``Oil-fired instantaneous water
heater'', ``Oil-fired storage water heater'', in its regulations of
consumer water heaters at 10 CFR 430.2 as set out in the regulatory
text at the end of this document.
Issue 9: DOE requests comment on its proposal to amend the
definitions for consumer water heaters codified at 10 CFR 430.2 by
removing the water temperature and storage capacity provisions. DOE
also requests comment on its proposal to remove the definitions at 10
CFR 430.2 for ``electric heat pump water heater'' and ``gas-fired heat
pump water heater.''
2. Commercial Water Heating Equipment
DOE currently includes several definitions that include the terms
``rated input'' or ``input rating'' in its regulations for CWH
equipment at 10 CFR 431.102. These definitions include ``hot water
supply boiler,'' ``instantaneous water heater,'' ``residential-duty
commercial water heater,'' and ``storage water heater.'' In section
III.K of this NOPR, DOE proposes a new definition for ``fuel input
rate,'' a value to be determined for all gas-fired and oil-fired CWH
equipment. Therefore, DOE proposes to replace the terms ``rated input''
and ``input rating'' with the term ``fuel input rate'' for gas-fired
and oil-fired CWH equipment in the definitions for CWH equipment at 10
CFR 431.102.
DOE's current definitions for ``storage water heater'' and
``instantaneous water heater'' in its regulations for CWH equipment
codified at 10 CFR 431.102 do not include any criteria that exclude
units that meet DOE's current definitions for consumer water heaters,
as codified at 10 CFR 430.2. Therefore, DOE proposes to clarify these
definitions for commercial water heaters by adding the input capacity
criteria that distinguish between consumer and commercial water heaters
for each energy source, as specified in EPCA's definition for consumer
water heater. (42 U.S.C. 6291(27)) These proposed changes are
consistent with DOE's proposed changes to its definitions for consumer
water heaters, as discussed in section III.F.1.
DOE currently includes the definition for ``instantaneous water
heater'' in its regulations for CWH equipment at 10 CFR 431.102. An
instantaneous water heater is a water heater that has an input rating
not less than 4,000 Btu/hr per gallon of stored water, and that is
industrial equipment, including products meeting this description that
are designed to heat water to temperatures of 180[emsp14][deg]F or
higher.
DOE believes that the last clause of the definition for
``instantaneous water heater,'' which includes units capable of heating
water to temperature at or above 180[emsp14][deg]F, does not serve a
purpose in the definition. Without this clause, it would be assumed
that units with this capability would be included in the definition
because there is no restriction indicating otherwise. Therefore to
simplify the definition, DOE proposes to remove this clause from the
definition for ``instantaneous water heater.'' Additionally, with DOE's
proposed addition of input criteria that distinguish between consumer
and commercial water heaters previously discussed in this section, DOE
believes that the clause ``that is industrial equipment'' does not
serve to further clarify the scope of units covered by this definition.
Therefore, DOE proposes to remove this clause from its definitions for
``instantaneous water heater'' and ``storage water heater,'' and
revises the definitions as set out in the regulatory text at the end of
this document.
In its regulations for CWH equipment at 10 CFR 431.102, DOE
currently includes a definition for ``packaged boiler'' that is
identical to that included for ``commercial packaged boiler'' at 10 CFR
431.82. DOE includes this definition for ``packaged boiler'' at 10 CFR
431.102 because the regulations for CWH equipment also include a
definition for ``hot water supply boiler,'' and this definition
specifies that a hot water supply boiler is a kind of packaged boiler.
To simplify its regulations and reduce repetition, DOE proposes to
remove the definition for ``packaged boiler'' from its regulations for
CWH equipment at 10 CFR 431.102. Consequently, in its definition for
``hot water supply boiler,'' DOE proposes to replace the term
``packaged boiler'' with the term ``packaged boiler (as defined in
Sec. 431.82).''
Issue 10: DOE requests comment on its proposed changes to its
definitions for CWH equipment: (1) Replacing the terms ``rated input''
and ``input rating'' with ``fuel input rate'' for gas-fired and oil-
fired CWH equipment to match DOE's proposed definition for ``fuel input
rate;'' (2) modifying DOE's definitions for ``instantaneous water
heater'' and ``storage water heater'' by adding the input criteria that
separate consumer water heaters and commercial water heaters and
removing several phrases that do not serve to clarify coverage of units
under the definitions; and (3) removing the definition of ``packaged
boiler.''
In section III.G, DOE discusses the reasons for a separate test
procedure for water heaters and hot water supply boilers that require
flow of water for heating water, and proposes a definition for ``flow-
activated water heater,'' along with a test procedure for flow-
activated water heaters as set out in the regulatory text at the end of
this document.
In section III.J, DOE proposes a definition for ``commercial heat
pump water heater,'' as well as a test procedure for commercial heat
pump water heaters as set out in the regulatory text at the end of this
document.
[[Page 28607]]
3. Residential-Duty Commercial Water Heaters
As required by AEMTCA, DOE established a uniform efficiency
descriptor and accompanying test method for consumer water heaters and
certain commercial water heaters in the July 2014 final rule. 79 FR
40542 (July 11, 2014). Specifically, AEMTCA required that the uniform
efficiency descriptor and test method apply to all covered water
heaters, including both consumer or commercial water heaters, except
for certain commercial water heaters that do not have a residential
use, can be clearly described, and are effectively rated using the
thermal efficiency and standby loss descriptors. (42 U.S.C.
6295(e)(5)(F)) In the July 2014 final rule, DOE established input and
volume criteria to distinguish commercial water heaters that do not
have residential applications, based on comments from stakeholders. 79
FR 40542, 40586 (July 11, 2014). However, for four classes of
residential-duty commercial water heaters--electric storage water
heaters, heat pump water heaters, gas-fired instantaneous water
heaters, and oil-fired instantaneous water heaters--the input criteria
established to separate residential-duty commercial water heaters and
commercial water heaters are identical to those codified at 10 CFR
430.2 that separate consumer water heaters and commercial water
heaters. The criteria for these classes are shown in Table III-1.
Because these input criteria are identical, by definition, no models
can be classified under these four residential-duty equipment classes.
Therefore, to eliminate potential confusion, DOE proposes to remove
these classes from the definition for ``residential-duty commercial
water heater'' codified at 10 CFR 431.102.
Table III-1--Indicator of Non-Residential Application for Certain
Classes of CWH Equipment
------------------------------------------------------------------------
Indicator of non-residential
Water heater class application
------------------------------------------------------------------------
Electric storage.................. Rated input >12 kW; Rated storage
volume >120 gallons.
Heat pump with storage............ Rated input >12 kW; Rated current
>24A at a rated voltage of not
greater than 250 V; Rated storage
volume >120 gallons.
Gas-fired instantaneous........... Rated input >200 kBtu/h; Rated
storage volume >2 gallons.
Oil-fired instantaneous........... Rated input >210 kBtu/h; Rated
storage volume >2 gallons.
------------------------------------------------------------------------
DOE proposes to revise the definition for ``residential-duty
commercial water heater'' as set out in the regulatory text at the end
of this document.
Issue 11: DOE requests comment on its proposal to modify the
definition of ``residential-duty commercial water heater'' by removing
from its scope the following classes: Electric storage water heaters,
heat pump water heaters with storage, gas-fired instantaneous water
heaters, and oil-fired instantaneous water heaters.
4. Storage-Type Instantaneous Water Heaters
The definitions for ``instantaneous water heater'' and ``hot water
supply boiler'' set forth in 10 CFR 431.102 include CWH equipment with
an input rating of at least 4,000 Btu/h per gallon of stored water.
These definitions, therefore, include both instantaneous water heaters
and hot water supply boilers without integral storage tanks, as well as
instantaneous water heaters with integral storage tanks (but with at
least 4,000 Btu/h of input per gallon of stored water). DOE believes
these two groups of equipment--water heaters with and without integral
storage tanks--are fundamentally different in their construction and
application and have different energy losses that need to be accounted
for during efficiency testing. DOE has tentatively concluded that
instantaneous water heaters with an integral storage tank (``storage-
type instantaneous water heaters'') should be tested in a manner
similar to commercial storage water heaters. Therefore, DOE proposes to
adopt a test method specifically applicable to ``storage-type
instantaneous water heaters'' that is the same as the test method for
commercial storage water heaters. DOE proposes to define ``storage-type
instantaneous water heater'' as set out in the regulatory text at the
end of this document.
Issue 12: DOE seeks comment on its proposed definition of
``storage-type instantaneous water heater.''
It is DOE's understanding that storage-type instantaneous water
heaters are very similar to storage water heaters, but with a higher
ratio of input rating to tank volume. This higher input-volume ratio is
achieved with a relatively larger heat exchanger paired with a
relatively smaller storage tank. However, through a review of product
literature, DOE noted no significant design differences between models
in these two proposed equipment classes that warrant separate test
procedures for thermal efficiency or standby loss. Therefore, DOE
proposes that the proposed test procedures for storage water heaters
apply also to storage-type instantaneous water heaters.
G. Standby Loss Test for Flow-Activated Instantaneous Water Heaters
The current Federal standby loss test method for CWH equipment
incorporates by reference ANSI Z21.10.3-2011, including Exhibit G.2
which assumes that the water heater would automatically initiate the
next firing cycle when the internal water temperature (measured using
the internal tank thermostat) falls below its allowable minimum value.
An underlying assumption for the standby loss test is that the ignition
of the burner or activation of the electric element is solely dependent
on the feedback control signal from the internal tank thermostat. This
assumption, although true for most CWH equipment, is not applicable to
certain instantaneous water heaters and hot water supply boilers that
require continuous water flow through the heat exchanger in order to
activate the next firing cycle.
Measuring standby loss for such flow-activated instantaneous water
heaters with a storage volume greater than or equal to 10 gallons was
raised as an issue by AHRI. (AHRI, No. 2 at pp. 4-5) Specifically, AHRI
commented that the current standby loss test is designed for tank-type
water heaters and does not address water heaters that can fire only
when hot water is being drawn. (AHRI, No. 2 at pp. 4-5) On August 25,
2014, AHRI provided a supplemental comment with a recommended standby
loss test method for tube-type instantaneous water heaters having a
capacity of 10 gallons or more (``2014 AHRI-recommended test method''),
which includes a suggested test method for models that are flow-
activated. AHRI also mentioned in its comments that their recommended
test method is being considered as an addition to the ANSI Z21.10.3
standard, and was at that time under review by the ANSI Z21/83
committee. (AHRI, No. 10 at p. 1)
DOE considered the comments received from AHRI and reviewed its
[[Page 28608]]
recommended standby loss test method for tube-type instantaneous water
heaters having a capacity of 10 gallons or more. Based on its review,
DOE agrees with AHRI's argument that the current standby loss test
method as set forth in Exhibit G.2 of ANSI Z21.10.3-2011 (incorporated
by reference in the DOE test procedures) is designed for
thermostatically-controlled, tank-type (or storage) water heaters and
acknowledges concerns about the applicability to flow-activated water
heaters. The current test procedure does not provide any indication of
how to test flow-activated instantaneous water heaters that have no
means of firing or heating if there is no flow of water through the
system. Therefore, DOE has tentatively concluded that a different
standby loss test procedure is required for flow-activated
instantaneous water heaters. To differentiate units for which the
proposed standby loss test procedure discussed in this section will
apply, DOE proposes to define ``flow-activated instantaneous water
heater'' as set out in the regulatory text at the end of this document.
Issue 13: DOE requests comment on its proposed definition for
``flow-activated instantaneous water heater.'' Specifically, DOE
requests feedback on whether the definition includes all units and
designs for which a separate standby loss test procedure is warranted,
and whether any units would be included that do not need a test method
separate from the current standby loss test procedure for CWH
equipment.
DOE notes that the requirement to measure a ``mean tank
temperature'' to calculate the standby loss would also be an issue for
all instantaneous water heaters and hot water supply boilers that have
a storage capacity of 10 gallons or more and that do not meet DOE's
proposed definition of ``storage-type instantaneous water heater'',
because these units do not have an integral tank, and the heat
exchanger geometry can make obtaining an accurate reading of the water
stored within the heat exchanger difficult to obtain. DOE has addressed
this issue both in its proposed test method for flow-activated
instantaneous water heaters contained within this section, and in
proposed changes to the current standby loss test procedure for other
instantaneous water heaters and hot water supply boilers discussed in
section III.I of this NOPR.
To develop a new Federal standby loss test procedure for flow-
activated instantaneous water heaters, DOE first reviewed the 2014
AHRI-recommended test method. After its review, DOE identified
potential issues and provided AHRI with questions seeking further
clarifications on various aspects of their recommended test method
related to conduct of the test, duration of test, flow and temperature
measurements, and the equations used to calculate standby loss. On
August 17, August 18, and December 14, 2015, DOE received separate
responses from AHRI members Thermal Solutions Inc., Raypak Inc. and A.
O. Smith, respectively.\13\ The responses provide answers to all the
questions posed by DOE and clarified the intent of the 2014 AHRI-
recommended test method.
---------------------------------------------------------------------------
\13\ The response from Thermal Solutions Inc. can be found in
the docket for this rulemaking at: http://www.regulations.gov/#!documentDetail;D=EERE-2014-BT-TP-0008-0011.
The response from Raypak Inc. can be found at: http://www.regulations.gov/#!documentDetail;D=EERE-2014-BT-TP-0008-0012.
The responses from A.O. Smith can be found at: http://www.regulations.gov/#!documentDetail;D=EERE-2014-BT-TP-0008-0014.
---------------------------------------------------------------------------
In November 2015, ANSI published an updated version of the ANSI
Z21.10.3 test standard. This updated version, ANSI Z21.10.3-2015,
includes Annex E.3, which describes a test method for measuring the
standby loss of tube-type instantaneous water heaters having a storage
capacity of 10 gallons or more. DOE reviewed this section carefully and
found it to be similar to the Annex E.3 included in the 2014 AHRI-
recommended test method. The only difference DOE identified between the
two versions of Annex E.3 was the referenced section for determining
the volume of water contained in the water heater. Specifically, Annex
E.3 in the 2014 AHRI-recommended test method references to section 5.27
of ANSI Z21.10.3 for determining the water contained in the water
heater, while Annex E.3 of ANSI Z21.10.3-2015 references section 5.28
of ANSI Z21.10.3-2015, ``Capacities of tube type water heaters.'' After
carefully comparing the 2014 AHRI-recommended test method with Annex
E.3 of ANSI Z21.10.3-2015, DOE believes that ANSI Z21.10.3-2015
renumbered section 5.27 as 5.28, and that AHRI's reference to section
5.27 was referring to the section titled ``Capacities of tube type
water heaters.'' Therefore, DOE has tentatively concluded that there
are no substantive differences between the 2014 AHRI-recommended test
method and the test method contained in Annex E.3 of ANSI Z21.10.3-
2015.
As previously discussed, prior to the publication of ANSI Z21.10.3-
2015, DOE posed several questions and sought clarifications from AHRI
on various aspects of the 2014 AHRI-recommended test method. Thermal
Solutions Inc., Raypak Inc., and A.O. Smith provided responses to DOE's
questions. The major issues on which DOE sought clarification, along
with the manufacturer responses, are described in the following
paragraphs.
First, DOE sought clarification as to whether the 2014 AHRI-
recommended test method applies to all tube-type (thermostatically-
activated and flow-activated) water heaters with a storage capacity of
10 gallons or more, or only to flow-activated instantaneous water
heaters. DOE notes that AHRI's comments indicate that the test
procedure is exclusively for flow-activated instantaneous water
heaters. However, the title of the 2014 AHRI-recommended test method
indicates that the test applies to all ``tube-type'' instantaneous
water heaters. (AHRI, No. 10 at p.4) Judging by the title and the
language used in the test method, DOE initially interpreted the test
method as divided into two distinct parts: (1) The first part
pertaining to tube-type instantaneous water heaters that are
thermostatically-activated and are not flow-activated; \14\ and (2) the
second part pertaining to water heaters that will neither initiate, nor
cause actions that will initiate, burner operation based on a
thermostatic control. DOE interpreted this second part of the test
procedure to be applicable to flow-activated instantaneous water
heaters that are not thermostatically-activated. However, the responses
from Raypak and Thermal Solutions indicate that the entire 2014 AHRI-
recommended test method (Annex E.3) is exclusively meant for flow-
activated instantaneous water heaters. Raypak and Thermal Solutions
stated that the first part of the test method is meant for water
heaters that are flow-activated but may have some other form of energy-
consuming function or water circulation during the conduct of the
standby loss test. (Thermal Solutions, No. 11 at p 1; Raypak, No. 12 at
p. 2) A.O. Smith also stated that DOE's interpretation was incorrect,
and that the 2014 AHRI-recommended test method is divided into two
parts to cover different designs of instantaneous water heaters whose
tube type heat exchangers happen to
[[Page 28609]]
store ten gallons or more. A.O. Smith further stated that the first
part of the test method addresses instantaneous water heaters whose
burners may activate by some specialty feature (e.g., frost control)
and the second part of the test method addresses more common designs
that are installed with a remote storage tank and a thermostat that
activates the water pump, which then activates the burners. A.O. Smith
also stated that the first part of the 2014 AHRI-recommended test
method does not address thermostatically-activated models. (A.O. Smith
No. 14 at p. 1)
---------------------------------------------------------------------------
\14\ The first equation for standby loss calculated in the first
part of 2014 AHRI-recommended test method includes a term for fuel
consumed. The test procedure also states that the second equation is
for units for which the main burner(s) do not cycle back on during
the course of the test. Based on this language, DOE interpreted the
first part (that includes the first and second equation) to be for
units that are thermostatically-activated and not flow-activated.
---------------------------------------------------------------------------
Thermal Solutions and Raypak did not comment on DOE's
interpretation of the second part of the 2014 AHRI-recommended test
method. However, judging by the response from A.O. Smith regarding the
second part and the responses from A.O. Smith, Thermal Solutions, and
Raypak regarding the first part, DOE infers that the second part of the
test procedure is meant for flow-activated instantaneous water heaters
that do not have any form of energy consumption or water circulation
during the conduct of the standby loss test. (Thermal Solutions, No. 11
at p 1; Raypak, No. 12 at p. 2; A.O. Smith No. 14 at p. 1)
DOE also sought clarifications on the equations used to calculate
the standby loss in both parts of the 2014 AHRI-recommended test
method. In the first equation of the 2014 AHRI-recommended test method,
DOE noticed an inconsistency in units of measurement. (AHRI, No. 10 at
p. 5) When calculated, the first term of this equation has the units
Btu/h, while the second term has the units 1/h. Mathematically, a
subtraction or addition operation cannot be applied over two numbers
that have different units of measurement. In their responses, the
manufacturers also acknowledged the issues with regards to the
equations for calculating standby loss and stated that AHRI has worked
on a corrected derivation for the equations of this test procedure.
(Thermal Solutions, No. 11 at p 3; Raypak, No. 12 at p. 4; A.O. Smith
No. 14 at p. 3) DOE notes that later versions of the AHRI-recommended
test methods (discussed later in this section) rectify this error in
the first equation of the 2014 AHRI-recommended test method. However,
the later versions of the AHRI-recommended test methods convert standby
loss units from percent-per-hour of the heat content of the stored
water to Btu-per-hour based on a temperature difference of the average
value of the outlet water temperature minus the average value of the
ambient temperature measured during the course of the test. This method
of calculation does not match with the standby loss definition that is
currently set forth in 10 CFR 431.102, which is based on a temperature
difference of 70[emsp14][deg]F between the stored water and the ambient
air. Therefore, DOE has tentatively decided not to consider this
equation for the proposed standby loss test procedure for flow-
activated instantaneous water heaters.
In the second equation of the 2014 AHRI-recommended test method,
DOE sought to understand the rationale for choosing a temperature
difference term that is equal to the difference between the outlet
water temperature and supply water temperature to calculate the thermal
energy lost during the test. (AHRI, No. 10 at p. 5) In the third
equation of the 2014 AHRI-recommended test method, DOE sought to
understand the rationale for assuming a constant temperature difference
of 70[emsp14][deg]F between the supply water and the outlet water
temperature. Further, the third equation appeared to assume that the
outlet water in the water heater will cool down to the supply water
temperature over a span of exactly 24 hours during the conduct of the
test. (AHRI, No. 10 at p. 6) On the issue of considering the
temperature difference between the outlet water temperature and supply
water temperature to calculate the loss in thermal energy during the
test, the manufacturers stated that AHRI has conservatively assumed the
temperature of stored water inside the water heater to be equal to the
outlet water temperature. The manufacturers stated that the geometry of
these water heaters does not allow for the measurement of the mean
stored water temperature inside the water heater. As a consequence, the
commenters suggested using the outlet water temperature in place of the
mean stored water temperature to carry out the standby loss
calculations. (Thermal Solutions, No. 11 at pp. 3, 5; Raypak, No. 12 at
pp. 4, 6; A.O. Smith No. 14 at pp. 3-5). The manufacturers also stated
that they are willing to accept a conservative estimate of the standby
loss in order to reduce the complexity and burden of the test method.
(Thermal Solutions, No. 11 at p. 3; Raypak, No. 12 at p. 4; A.O. Smith
No. 14 at p. 3-5)
DOE also sought clarification on the duration of the standby loss
test. In particular, DOE sought an answer to whether any consideration
was given to the possibility that flow-activated water heater burners
may not cycle on at any point during the test and instead cool down
completely in less than 24 hours. The manufacturers' responses to this
question indicated that the suggested test method includes a one-hour
test, and it is assumed that all the heat is lost in the heat
exchanger. (Thermal Solutions, No. 11 at p 4; Raypak, No. 12 at p. 4;
A.O. Smith No. 14 at p. 5)
Another issue that DOE sought clarification on is the method used
to measure the storage volume of the water heater. Section 5.27 of ANSI
Z21.10.3-2015 (that is the same as section 5.26 of ANSI Z21.10.3-2011,
2013, and 2014), ``Capacities of storage vessels,'' describes a method
of test to measure the storage volume of a water heater containing a
storage vessel or with an input rating less than 4,000 Btu/h per gallon
of water stored. The 2014 AHRI-recommended test method specifies using
the methodology described in section 5.27 of ANSI Z21.10.3, that DOE
believes corresponds to section 5.28 of ANSI Z21.10.3-2015,
``Capacities of tube type water heaters.'' DOE reviewed section 5.28 of
ANSI Z21.10.3-2015 carefully, and noticed that this section does not
specify a method for determining the volume of tube-type water heaters;
instead, it only states that the volume shall be determined. DOE sought
clarifications on the rationale for using the test method described in
section 5.28, ``Capacities of tube type water heaters'' of ANSI
Z21.10.3-2015 as opposed to section 5.27, ``Capacities of storage
vessels'' of ANSI Z21.10.3-2015 (that is the same as section 5.26 of
ANSI Z21.10.3-2011, 2013 and 2014). Section 5.26 of ANSI Z21.10.3-2011
is used for measuring the storage volume of all CWH equipment in
Exhibit G.2 of ANSI Z21.10.3-2011, which is incorporated by reference
in the current Federal standby loss test procedure.
In response to this issue, the manufacturers stated that
determining the stored volume using section 5.26 of ANSI Z21.10.3
(which DOE interprets as referring to section 5.26 of ANSI Z21.10.3-
2011, 2013, and 2014, ``Capacities of storage vessels,'' which
corresponds to section 5.27 of ANSI Z21.10.3-2015) is only required for
water heaters that are known to have a stored water capacity greater
than or equal to ten gallons and that the test is not required for
water heaters with less than ten gallons of storage capacity. The
manufacturers' comments indicate that they believe the test method to
measure the storage volume is left to the discretion of the
certification body. The manufacturers further stated that the test
method in section 5.26 may not be a reliable test method for water
heaters with small water volumes, manifold coils, and complex
geometries. Moreover, they stated that heat exchangers used in the
water heaters are
[[Page 28610]]
hydrostatically tested before the assembly, as required by the American
Society of Mechanical Engineers (ASME) and will always have some
residual water in the heat exchanger. According to the manufacturers,
this residual water will result in inaccurate measurement of the
volumetric capacity of the water heater. (Thermal Solutions, No. 11 at
pp. 1-2; Raypak, No. 12 at p. 2; A.O. Smith No. 14 at pp. 1-2)
Another issue that DOE noticed with the test procedure in Annex E.3
of ANSI Z21.10.3-2015 is that (similar to the 2014 AHRI-recommended
test method) the first part of Annex E.3 of ANSI Z21.10.3-2015 appears
to be for thermostatically-activated units. Annex E.3 of ANSI Z21.10.3-
2015 does not appear to be applicable exclusively to flow-activated
instantaneous water heaters as is indicated by the manufacturers in
their responses and AHRI in the 2014 AHRI-recommended test method.
(AHRI, No. 10 at p. 4; Thermal Solutions, No. 11 at pp. 1; Raypak, No.
12 at pp. 1-2; A.O. Smith, No. 14 at p. 1)
On December 2, 2015, AHRI submitted another supplemental comment to
the February 2014 RFI that included a revised recommendation for a test
method for measuring standby loss for tube-type commercial
instantaneous water heaters and hot water supply boilers that contain
more than 10 gallons of water (``2015 AHRI-recommended test method'').
(AHRI (2015), No. 13, pp.1, 6-8) \15\ DOE compared the 2014 AHRI-
recommended test method with the 2015 AHRI-recommended test method to
identify the differences between the two test methods. In the 2015
AHRI-recommended test method, AHRI updated the equations for
calculation of standby loss in its recommended Annex E.3. After
reviewing these revised equations, DOE notes that the first equation in
Annex E.3 of the 2015 AHRI-recommended test method is the result of
converting the current equation for standby loss specified in Exhibit
G.2 of ANSI Z21.10.3-2011 (but with the mean tank temperature replaced
with the outlet water temperature) from units denominated as
percentage-per-hour to units denominated as Btu-per-hour, by
multiplying by a term consisting of k x Va x
[Delta]T3/100.\16\ DOE also notes that the second equation
provided in the 2015 AHRI-recommended test method is identical to the
second equation that is provided in the 2014 AHRI-recommended test
method and as stated in the test method, is used for water heaters for
which the main burner(s) do not cycle on during the course of the test.
The final equation in the 2015 AHRI-recommended test method specifies
the time for the duration of the test as 24 hours, similar to the 2014
AHRI-recommended test method. However, in the 2015 AHRI-recommended
test method, the variables used in the final equation and the variables
defined after the equation are not consistent--specifically, the
equation contains the term [Delta]T4, while the list of
variables below the equation includes [Delta]T5. The final
equation in the 2015 AHRI-recommended test method uses
[Delta]T4, while the final equation in the 2014 AHRI-
recommended test method uses [Delta]T5. Other than the
differences mentioned in this paragraph, DOE tentatively determined
that the 2015 AHRI-recommended test method contains no additional
substantive differences from the previously submitted 2014 AHRI-
recommended test method. Therefore, other than these differences, all
issues that DOE identified with the standby loss test in the 2014 AHRI-
recommended test method also apply to the 2015 AHRI-recommended test
method.
---------------------------------------------------------------------------
\15\ DOE received two supplemental comments from AHRI in
response to the February 2014 RFI on December 2, 2015 and January
11, 2016. Both comments are included in the docket under filing
number EERE-2014-BT-TP-0008-0013. To differentiate between the two
documents for citations, DOE uses ``AHRI (2015)'' and ``AHRI
(2016)'' to refer to the comment received on December 2, 2015 and on
January 11, 2016, respectively. Both supplemental comments can be
found at: http://www.regulations.gov/#!documentDetail;D=EERE-2014-
BT-TP-0008-0013.
\16\ Annex E.2 of ANSI Z21.10.3-2013 (and 2014) defines `K' as
the nominal specific heat of water that has a value of 8.25 Btu per
gallon. This is the same as `k' that is used by AHRI in their
equations in the Annex E.3 of the 2015 and 2016 AHRI-recommended
test method. The term Va refers to the measured volume expressed in
gallons and measured as per section 5.27 of ANSI Z21.10.3-2015 and
[Delta]T3 refers to the difference between the average
value of the outlet water temperature and the average value of the
ambient temperature expressed in [deg]F.
---------------------------------------------------------------------------
On January 11, 2016, AHRI submitted a third supplemental comment to
the February 2014 RFI that included a further revised recommendation
for a test method for measuring standby loss for tube-type commercial
instantaneous water heaters and hot water supply boilers that contain
more than 10 gallons of water (``2016 AHRI-recommended test method'').
(AHRI (2016), No. 13, pp.1, 6-8) After carefully reviewing this
submission, DOE tentatively determined that the only difference between
the 2015 AHRI-recommended test method and the 2016 AHRI-recommended
test method are the temperature differences used in equations for
calculating standby loss. Specifically, the temperature difference used
in the first two equations in Annex E.3 of the 2016 AHRI-recommended
test method is [Delta]T5, which represents the difference
between the final outlet water temperature and the initial outlet water
temperature. This differs from the temperature difference terms used in
the corresponding standby loss equations in the 2015 AHRI-recommended
test method, which are denoted as [Delta]T4 and defined as
the difference between the average supply water temperature and the
outlet temperature. In the final standby loss equation in Annex E.3,
the temperature difference used is [Delta]T6, which
represents 70[emsp14][deg]F, the difference between the supply and
outlet water temperatures, and was previously denoted as
[Delta]T5 in the corresponding equation in the 2015 AHRI-
recommended test method. These changes in temperature difference terms
in standby loss equations help to clarify issues with these terms that
DOE identified in the 2015 AHRI-recommended test method. However, with
the exception of these temperature difference terms, the other issues
that DOE identified with the 2014 and 2015 AHRI-recommended test
methods also apply to the 2016 AHRI-recommended test method.
DOE has considered the initially submitted 2014 AHRI-recommended
test method, the clarifications provided by manufacturers, Annex E.3 of
the recently published ANSI Z21.10.3-2015, and the recently submitted
2015 and 2016 AHRI-recommended test methods in developing the proposed
standby loss test procedure for flow-activated instantaneous water
heaters. DOE agrees with certain aspects of the recommended test
methods and the related clarifications; however, DOE tentatively
concludes that there are several modifications that need to be made to
the 2016 AHRI-recommended test method for it to be used as a Federal
standby loss test procedure for flow-activated instantaneous water
heaters. As noted previously, the only difference between the 2016
AHRI-recommended test method and Annex E.3 of ANSI Z21.10.3-2015 is
with regards to the first equation in both test methods and, similarly,
DOE is not proposing to adopt the test method in Annex E.3 as the
Federal test method. Rather, the following paragraphs describe DOE's
proposed test method, including differences from both the 2016 AHRI-
recommendation and the ANSI Z21.10.3-2015 test method, and the reasons
such changes are deemed necessary.
As previously defined in this section, a flow-activated
instantaneous water heater will initiate firing or heating only
[[Page 28611]]
when water is being drawn from the water heater. In Annex E.3 of ANSI
Z21.10.3-2015 and the 2016 AHRI-recommended test method, the water
heater is kept in standby mode, and no hot water is drawn from the
equipment during the standby loss test. Under such conditions, the
water heater would not be expected to initiate burner or heating
element operation at any point during the course of the test since
there is no flow to activate the heat source. As a result, hot water
stored in the water heater in standby mode will continuously lose heat
to the environment until the water temperature approaches the
surrounding ambient air temperature. DOE considers this standby mode
operation for flow-activated instantaneous water heaters to be
characteristically different from the standby mode operation of
thermostatically-activated water heaters, where the main burner or
element(s) cycles on when the water temperature drops below the
thermostat set point.
The first part of Annex E.3 of ANSI Z21.10.3-2015 and the 2016
AHRI-recommended test method appears to apply to water heaters that may
circulate water or initiate some other energy-consuming function when
hot water is not being drawn. If a water heater consumes energy for the
purpose of heating water during the standby mode, then such a water
heater would not fit the proposed definition of a ``flow-activated
instantaneous water heater.'' Such water heaters would instead be
covered by the proposed standby loss test method for instantaneous
water heaters and hot water supply boilers that are not flow-activated,
as discussed in section III.I of this NOPR. However, to account for
other types of fuel consumption during standby mode (i.e., other than
directly for the purpose of heating water), DOE has retained the fuel
consumption terms in the proposed standby loss equation for flow-
activated instantaneous water heaters.
The driving temperature difference that causes the constant heat
loss to the ambient air from the water heater is the difference between
the stored water and the ambient air temperature. This temperature
difference must be factored into the standby loss calculations, as
included in the 2016 AHRI-recommended test method, instead of the
temperature difference between outlet and supply water that is used in
Annex E.3 of ANSI Z21.10.3-2015 and the 2015 AHRI-recommended test
method. In addition, the current standby loss test procedure that is
set forth in Exhibit G.2 of ANSI Z21.10.3-2011 (incorporated by
reference into the current DOE test procedure) calculates the standby
loss as a percentage per hour of the total heat content of the water
heater. In DOE's test procedure for gas-fired and oil-fired CWH
equipment as set forth in 10 CFR 431.106, DOE uses this percent-per-
hour standby loss value to calculate the standby loss in terms of Btu/h
based on the storage volume and a 70[emsp14][deg]F temperature
difference between the stored water and the ambient air temperature.
DOE notes that the 2016 AHRI-recommended test method converts from
standby loss in terms of percent-per-hour to standby loss in terms of
Btu-per-hour by multiplying by a term that includes
[Delta]T3, which is defined in Annex E.3 of ANSI Z21.10.3-
2015 as the difference between the outlet water temperature and the
average value of the ambient temperature. This is in contrast to: (1)
DOE's current test procedure as specified in 10 CFR 431.106, which
converts using a fixed 70[emsp14][deg]F temperature difference rather
than using the measured temperature difference from testing and, (2)
the current definition of ``standby loss'' specified in 10 CFR 431.102
that defines ``standby loss'' as the average energy required to
maintain the stored water temperature, expressed in Btu per hour based
on a 70[emsp14][deg]F temperature differential between stored water and
ambient temperature.
DOE notes that use of a fixed 70[emsp14][deg]F temperature
difference allows for straightforward conversion of standby loss from
one set of units to another, while use of the measured temperature
difference requires the availability of data from efficiency testing.
DOE sees value in such a straightforward conversion, so that those
without access to efficiency test data can still convert between the
two values. Additionally, the standby loss test method that is proposed
for flow-activated instantaneous water heaters already takes into
account the measured temperature difference between the outlet water
temperature and the ambient air temperature, making the additional
inclusion of this term in the conversion unnecessary. Finally, use of a
constant 70[emsp14][deg]F temperature difference would make the
conversion in this proposed standby loss test procedure consistent with
that in DOE's current test procedure at 10 CFR 431.106, and DOE also
proposes this method of conversion to standby loss in terms of Btu/h
for other classes of gas-fired and oil-fired CWH equipment in
appendices A and C to subpart G of 10 CFR part 431. Therefore, DOE
proposes to use the same approach of a constant 70[emsp14][deg]F
temperature difference to calculate the standby loss for gas-fired and
oil-fired flow-activated instantaneous water heaters. For electric
flow-activated instantaneous water heaters, DOE proposes to maintain a
standby loss metric in terms of a percent-per-hour value.
As discussed in this preamble, the 2016 AHRI-recommended test
method specifies setting a time duration of one hour for flow-activated
water heaters that would not have any form of energy consumption to
maintain the water temperature and that would eventually cool down to
ambient temperature. DOE sees merit in setting a maximum time duration
to mark the end of the test. However, DOE does not agree with having
the time duration as the only criterion for ending the standby loss
test. As noted previously, the standby loss test for flow-activated
instantaneous water heaters resembles a constant cool down test where
the main burner or heating element does not cycle on at any point in
the course of the test. For these water heaters, it is very likely that
the stored water in the unit cools down to the ambient temperature
before 24 hours. In such a scenario, from the time the stored water
temperature reaches the ambient temperature to the end of the 24 hours,
the water heater will not experience any standby energy loss. However,
the standby loss equation provided in the 2016 AHRI-recommended test
method assumes that the entire heat loss takes place over a duration of
24 hours. As a result, using the 2016 AHRI-recommended test method, the
standby loss value calculated for water heaters that cool down before
the 24-hour time period would understate the actual hourly heat loss
from the water heater. Based on the 2016 AHRI-recommended test method,
two water heaters that have the same storage volume and electricity
consumption but different cooling rates as they both cool down to the
ambient temperature within 24 hours would have the same standby loss
value. DOE has determined that this would lead to an inaccurate
comparison of the standby loss between two water heaters that lose heat
at different rates. A similar issue would arise if the time duration
were set to one hour or any specific value that might be less than the
time it takes some water heater to cool to ambient temperature, because
such a time criterion would capture the heat loss to different final
water temperatures for different water heaters (i.e., two different
water heaters would have different final water temperatures at the end
of the set time period). This
[[Page 28612]]
variation in final water temperature would impart an undesirable
benefit to water heaters that lose heat more quickly, because the rate
of heat transfer from water to the surrounding air decreases as the
corresponding temperature difference decreases.
To avoid these issues and to compare standby loss of different
water heaters with a more consistent approach, DOE proposes to use a
temperature criterion in addition to a fixed maximum time duration to
mark the end of the test. DOE proposes that the standby loss test be
stopped at the first instance that the measured outlet water
temperature is 35[emsp14][deg]F below the outlet water temperature
measured at the start of the test. If the specified temperature drop in
the outlet water temperature does not occur within a 24 hour time
period then the test shall be stopped at the end of 24 hours from the
start of the test.
Finally, DOE must specify a method for determining the storage
volume of the water heater. The manufacturers' responses stated that
for some water heaters, it will not be necessary to measure the volume
if it is less than 10 gallons. Although DOE does not currently
prescribe a standby loss standard for instantaneous water heaters and
hot water supply boilers with a storage volume below 10 gallons, DOE
requires certification of the rated storage volume for all gas-fired
and oil-fired instantaneous water heaters and hot water supply boilers.
These certification requirements are set forth at 10 CFR
429.44(c)(2)(iv) and (v).
Because flow-activated instantaneous water heaters have heat
exchanger designs similar to thermostatically-activated instantaneous
water heaters, the issue of measuring the storage volume applies to all
instantaneous water heaters and hot water supply boilers. Exhibit G.2
of ANSI Z21.10.3-2011 (that is incorporated by reference into the
current DOE test procedure) references section 5.26 of the same testing
standard as a method to measure the storage volume of CWH equipment. In
response to the February 2014 RFI, HTP raised an issue with regards to
the measurement of storage volume for instantaneous water heaters and
hot water supply boilers. HTP commented that due to various geometries
and sizes, measurement of the storage volume by a third-party
laboratory or manufacturer's facility would be difficult and may
produce inconsistent results. (HTP, No. 5 at p. 2) As discussed
earlier, this issue was also raised by manufacturers in response to
DOE's questions on the 2014 AHRI-recommended standby loss test method
for flow-activated instantaneous water heaters.
DOE acknowledges the issues highlighted by manufacturers regarding
use of section 5.26 of ANSI Z21.10.3-2011 (which corresponds to section
5.27 of ANSI Z21.10.3-2015) to measure the storage volume of
instantaneous water heaters and hot water supply boilers, including
flow-activated and thermostatically-activated units. To find
alternatives to this test method, DOE investigated other options for
measuring the storage volume of such water heaters. Through its review,
DOE did not identify an alternative test method suitable to measure the
storage volume of instantaneous water heaters and hot water supply
boilers that would not significantly increase the testing burden for
manufacturers. Moreover, section 5.28, ``Capacities of tube type water
heaters,'' of ANSI Z21.10.3-2015 does not specify a test method to
measure the storage volume. Instead, section 5.28 of ANSI Z21.10.3-2015
only states that the ``volume contained in the water heater shall be
determined.'' The wording of this section and the manufacturers'
responses on this test method appear to suggest that the actual method
of determination of the volume is left to the discretion of the testing
agency.
The test method in section 5.27 of ANSI Z21.10.3-2015 requires the
water heater to be weighed dry and empty, and then reweighed when
filled with water. The difference in the two values of the weight
equate to the weight of the stored water in the water heater. The
weight of stored water can be converted into gallons by dividing by the
density of water. Although section 5.27 of ANSI Z21.10.3-2015
specifically states that the test be used for storage vessels or water
heaters having an input rating of less than 4,000 Btu/h per gallon of
capacity, the test method appears to be applicable to any CWH equipment
that can be weighed both dry and after being filled with water. The
energy conservation standards for instantaneous water heaters are
dependent on the rated storage volume. The rated storage volume is
needed to determine the appropriate equipment class and, for units with
storage volume greater than or equal to 10 gallons, it is required to
calculate the standby loss standard. Therefore, DOE must specify a test
method to measure the storage volume of water heaters, rather than
leave the decision of the appropriate method (e.g., direct measurement,
calculation) to individual manufacturers or testing agencies, who may
choose different methods for determining the storage volume, which
could provide inconsistent results. Based on the foregoing reasoning,
and the lack of alternative test methods to measure the storage volume,
DOE tentatively concluded that the method presented in section 5.27 of
ANSI Z21.10.3-2015 should be used for measurement of the storage volume
of instantaneous water heaters and hot water supply boilers that do not
meet DOE's proposed definition for ``storage-type instantaneous water
heater,'' including thermostatically-activated and flow-activated
instantaneous water heaters. However, because section 5.27 of ANSI
Z21.10.3-2015 includes a limitation that the method is only applicable
to units containing storage vessels, DOE proposes not to incorporate
this section by reference, and instead proposes a test procedure very
similar to the method in section 5.27 of ANSI Z21.10.3-2015, with only
clarifying changes. Specifically, DOE proposes to remove the limitation
that only storage vessels or water heaters having an input rating of
less than 4,000 Btu/h per gallon of capacity can be tested using this
method, and clarifies that the density of water at the measured water
temperature is to be used to convert from the weight of water to the
volume in gallons.
Issue 14: DOE requests comment on its proposal to include a test
procedure similar to that specified in section 5.27 of ANSI Z21.10.3-
2015 for measuring the storage volume of all instantaneous water
heaters and hot water supply boilers, including flow-activated
instantaneous water heaters. DOE also seeks information on alternative
methods for measuring storage volume and the impact of residual water
on measuring storage volume of instantaneous water heaters and hot
water supply boilers. Further, DOE seeks comment on ways to remove
residual water from the water heater that could allow for more accurate
and consistent measurement of the storage volume of CWH equipment.
Based on the AHRI-recommended test methods and the responses
received from manufacturers, DOE proposes a new standby loss test
procedure for flow-activated instantaneous water heaters. The proposed
test procedure is based on the 2016 AHRI-recommended test method,
specifically the second part of the test method that applies to flow-
activated water heaters that will not initiate burner operation over
the course of the test. However, in developing the proposed test
method, DOE has departed from the 2016 AHRI-recommended test method in
several areas, including the method of test, time duration, and
equations to calculate standby loss. DOE also conducted
[[Page 28613]]
investigative testing on flow-activated instantaneous water heaters
that helped inform the proposals made to this test procedure. The
following paragraphs describe DOE's proposed test method for measuring
the standby loss of flow-activated instantaneous water heaters. The
proposed test procedure is also included in the proposed regulatory
text for appendix E to subpart G of part 431.
The proposed standby loss test for flow-activated instantaneous
water heaters can be started immediately after the thermal efficiency
test, using the same test set-up and test conditions. Otherwise, if the
standby loss test is conducted separately, install the water heater as
per the specifications in section 2 of appendix E to subpart G of part
431. As discussed in section III.H, DOE proposes required locations for
temperature-sensing instrumentation for instantaneous water heaters and
hot water supply boilers, including flow-activated instantaneous water
heaters. For water heaters with multiple outlet water connections
leaving the water heater jacket, apply the test set-up provisions
proposed in section III.H (also included in appendix C to subpart G of
part 431). The representative value of the outlet water temperature
used for the standby loss calculations is obtained by taking the
average of the water temperatures measured at each water connection
leaving the water heater jacket. DOE proposes that the test entity set
the data acquisition system to record the supply water temperature,
outlet water temperature, ambient room temperature, and electrical
consumption (as applicable) at intervals of every 30 seconds.
DOE proposes the test be conducted as follows:
Once the water heater is set up, supply water to the equipment
being tested as per section (d) of Annex E.1 of ANSI Z21.10.3-2015.
Adjust the water flow rate in such a way that the outlet water reaches
a temperature of 70[emsp14][deg]F 2[emsp14][deg]F above
the supply water temperature. After the outlet water temperature has
remained constant with no variation of more than 2[emsp14][deg]F over a
3-minute period and maintains a temperature of 70[emsp14][deg]F 2[emsp14][deg]F above the supply water temperature, turn off the
supply and outlet water valves that are installed closest to the water
heater (as per the provisions in appendix C to subpart G of part 431),
and the water pump, simultaneously. Allow the water heater to cut-out.
Immediately after the cut-out, begin recording measurements for the
standby loss test.
At this time, start the clock and record the initial outlet water
temperature, ambient room temperature, and fuel (and electricity) meter
reading. Continue to monitor and record the outlet water temperature,
the ambient room temperature, the time elapsed from the start of the
test, and the electricity consumption at 30-second intervals using a
data acquisition system.
Stop the test if the outlet water temperature decreases by
35[emsp14][deg]F from the initial outlet water temperature within 24
hours from the start of the test. Record the final outlet water
temperature, final ambient room temperature, fuel consumed, electricity
consumed, and the time elapsed from the start of the test.
If the outlet water temperature does not decrease by
35[emsp14][deg]F from the initial outlet water temperature within 24
hours from the start of the test, then stop the test after 24 hours
from the start of the test. Record the final outlet water temperature,
final ambient room temperature, fuel consumed, electricity consumed,
and the time elapsed from the start of the test.
Use the equation below to calculate the standby loss in terms of
percent of total heat content per hour.
[GRAPHIC] [TIFF OMITTED] TP09MY16.270
>Where,
[Delta]T1 = Outlet water temperature measured at the
start of the test minus outlet water temperature measured at the end
of the test, expressed in [deg]F
[Delta]T2 = Outlet water temperature at the start of the
test minus the ambient room temperature at the start of the test,
expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons
Et = Thermal efficiency of the water heater. For electric
water heaters with immersed heating elements use 98 percent.
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
Cs = Correction applied to the heating value of a gas H,
when it is metered at temperature and/or pressure conditions other
than the standard conditions upon which the value of H is based.
Cs is not applicable to oil-fired equipment.
Qs = Total fuel flow as metered for gas-fired and oil-
fired equipment, expressed in ft\3\ (gas) or lb (oil)
H = Higher heating value of gas, expressed in Btu/ft\3\ (gas) or
Btu/lb (oil)
t = Total duration of the test in hours
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the initial
heat content of the stored water above room temperature
For gas-fired and oil-fired flow-activated instantaneous water
heaters, to calculate the standby loss in terms of Btu per hour, use
the following equation:
SL = S% x K (Va)(70 [deg]F)
Where, SL refers to the standby loss of the water heater, defined
as the amount of energy required to maintain the stored water
temperature expressed in Btu per hour.
Issue 15: DOE requests comment from interested parties on all
aspects of the proposed test procedure for flow-activated instantaneous
water heaters. Specifically, DOE requests comment on its tentative
decision to: (1) Base the test procedure on the second part of the 2016
AHRI-recommended test method that applies to flow-activated water
heaters that will not initiate burner operation over the course of the
test; (2) stop the test following a 35[emsp14][deg]F
2[emsp14][deg]F drop in the outlet water temperature or completion of
24 hours, whichever occurs earlier; and (3) use the outlet water
temperature as an approximation of the stored water temperature.
H. Test Set Up for Commercial Instantaneous Water Heaters and Hot Water
Supply Boilers
The current thermal efficiency and standby loss test methods as
described in ANSI Z21.10.3-2011 require commercial instantaneous water
heaters and hot water supply boilers to be set up in accordance with
Figure 2 of that test standard. Although the figure is not drawn to
scale and no measurements are specified, DOE notes that the
temperature-sensing instruments for measuring outlet water temperature
appear to be placed at a considerable distance away from the water
heater being tested. Measuring the temperature at a significant
distance away from the water heater could lead to an inaccurate
representation of the outlet water temperature due to heat loss in the
piping. Even if the pipes are insulated,
[[Page 28614]]
measuring temperature as close as possible to the outlet ports or
possibly inside the port would yield a more accurate representation of
the outlet water temperature. The heat loss from the piping would be
higher while conducting the standby loss tests that could run for
several hours to a maximum of 24 hours for flow-activated instantaneous
water heaters and from 24 to 48 hours for other instantaneous water
heaters and hot water supply boilers. Moreover, the new standby loss
test procedure that is proposed for flow-activated instantaneous water
heaters in this NOPR uses the outlet water temperature as an
approximation for the stored water temperature inside the water heater.
Therefore, it is important that the outlet water temperature be
measured as close as possible to the water heater to minimize the
effect of piping heat losses while conducting the standby loss test.
To address these issues, DOE proposes to specify the location and a
set of requirements for placement of the temperature sensors to ensure
that they accurately represent the outlet water temperature for the CWH
equipment. Specifically, DOE proposes that the tip or junction of the
temperature sensor be placed: (1) In the water; (2) less than or equal
to 5 inches away from the water heater jacket; (3) about the central
axis of the water pipe; and (4) with a radiation protection shield. The
type and number of temperature-sensing instruments is left to the
discretion of the testing operator.
Certain instantaneous CWH models have multiple outlet water
connections leaving the jacket that are combined externally using
common piping. For such units, DOE proposes that the temperature sensor
placement conditions as proposed in the paragraph above be applied to
each outlet water connection leaving the water heater jacket. To
clarify, DOE proposes that for each outlet water connection leaving the
water heater jacket, the temperature sensor be placed: (1) in the
water; (2) less than or equal to 5 inches away from the water heater
jacket; (3) about the central axis of the water pipe; and (4) with a
radiation protection shield. For obtaining a single outlet water
temperature value that is representative of the entire water heater,
DOE proposes to take the average of the all outlet water temperature
measurements (for each outlet water connection leaving the water heater
jacket) for each recording of the data-acquisition unit. In addition to
these provisions, DOE also proposes that while verifying steady-state
operation (prior to the thermal efficiency test) and during the thermal
efficiency test, the water temperatures recorded for each outlet water
connection leaving the water heater jacket must: (1) Be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature, and (2) not differ from each other by more than
2[emsp14][deg]F.
Figure III.4, an adaptation of Figure 3 of ANSI Z21.10.3-2015,
shows DOE's proposed location requirements for the temperature-sensing
instruments for measuring the inlet and outlet water temperature of
instantaneous water heaters (other than storage-type instantaneous
water heaters) and hot water supply boilers.
The current test procedure for instantaneous water heaters and hot
water supply boilers does not clearly indicate the location and
installation of the supply and outlet water valves. To obtain accurate
measurements during standby operation, the water supply must be cut off
to prevent mixing of water in the piping lines with that in the water
heater during the standby loss test. To address this issue, DOE
proposes to require supply and outlet water valves to be installed
within a specified distance of the water heater. Specifically, for
instantaneous water heaters and hot water supply boilers shipped
without external piping installed at the point of manufacture, DOE
proposes to require the supply water valve to be installed within 5
inches of the jacket, and the outlet water valve to be installed within
10 inches of the jacket. For instantaneous water heaters and hot water
supply boilers with external piping assembled at the manufacturer's
premises prior to shipment, DOE proposes to require the supply and
outlet water valves to be installed within 5 inches of the end of the
piping shipped with the unit. DOE also proposes that the supply and
outlet water valves be used to turn off the water flow at the start of
the standby loss test for instantaneous water heaters and hot water
supply boilers (including ``flow-activated instantaneous water
heaters''). Figure III.4 shows the location of the valves with respect
to other instrumentation used in the test set-up for units shipped
without external water piping installed.
The current Federal thermal efficiency test as set forth in 10 CFR
431.106, incorporates by reference Exhibit G.1 of ANSI Z21.10.3-2011,
which requires the supply water temperature to be 70[emsp14][deg]F
2[emsp14][deg]F and the outlet water temperature to be
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature with the burner or heating element operating at its full
firing rate. Certain instantaneous water heaters and hot water supply
boilers, including flow-activated instantaneous water heaters that are
designed to operate at higher inlet water temperatures, may not be able
to achieve such a temperature rise. The current test procedure
addresses this issue by allowing for the use of a recirculating loop
(see Figure 3 of ANSI Z21.10.3-2015). Section 5.1.7 of ANSI Z21.10.3-
2015 (which contains Figure 3) also requires that the specified inlet
water temperature shall not be less than 70[emsp14][deg]F or more than
120[emsp14][deg]F. In this NOPR, DOE proposes to retain the option of
using a recirculating loop and the limits on the inlet water
temperature for instantaneous water heaters and hot water supply
boilers that are not able to meet the outlet water temperature
requirement at the full firing rate. DOE proposes to explicitly state
the conditions for using a recirculating loop (i.e., that the unit
under test is unable to meet the outlet temperature at the full firing
rate) and to specify the limits set on the inlet water temperature
(measured at T5), as contained in section 5.1.7 of ANSI
Z21.10.3-2015. Figure III.4 shows the arrangement for optional use of a
recirculating loop. DOE proposes to clarify that the supply water
temperature measured at T1 must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F during the entire course
of the thermal efficiency test (as applicable) and prior to starting
the standby loss test, while the temperature measurement at
T5 must not be less than 70[emsp14][deg]F or more than
120[emsp14][deg]F.
[[Page 28615]]
[GRAPHIC] [TIFF OMITTED] TP09MY16.271
Figure III.4 and the proposed specifications for the placement of
temperature sensors, placement of water valves, and placement of a
recirculating loop (when used) are included in appendix C to subpart G
of part 431.
Issue 16: DOE seeks comment on its proposed change to the location
of temperature measurement for the outlet water temperature with the
associated conditions for placement of temperature-sensing instruments
in water pipes, as well as the placement of the supply and outlet water
valves. Specifically, DOE requests comment on whether such a change
would provide more accurate test results, and whether the change would
be burdensome to manufacturers. Additionally, DOE requests information
on any alternative arrangements to measure the outlet water temperature
accurately and in close proximity to the hot water outlet of the tested
CWH equipment.
I. Changes to the Standby Loss Test for Instantaneous Water Heaters and
Hot Water Supply Boilers Other Than Flow-Activated Instantaneous Water
Heaters
Currently, all instantaneous water heaters and hot water supply
boilers having a storage capacity of ten gallons or more are required
to be tested for standby loss as per the test method in Exhibit G.2 of
ANSI Z21.10.3-2011, which is incorporated by reference into DOE's
current test procedure. In the February 2014 RFI, DOE sought comments
on the repeatability of thermal efficiency and standby loss test
methods included in the ANSI Z21.10.3-2011 and ANSI Z21.10.3-2013 test
methods. 79 FR 10999, 11001-02 (Feb. 27, 2014). DOE discussed the
comments received in response to this issue generally in section III.B
of this NOPR. In its response to this issue, HTP stated that currently,
there is no standby loss test method that is suitable for hot water
supply boilers containing ten gallons or more of stored water. (HTP,
No. 5 at p. 2) While responding to a different issue related to the
applicability of standby loss test procedure to flow-activated water
heaters, AHRI commented that the current standby loss test procedure is
designed for tank-type water heaters which are thermostatically-
activated. (AHRI, No. 2 at p. 4)
DOE reviewed the comments made by HTP and AHRI with regards to the
standby loss test procedure for instantaneous water heaters and hot
water supply boilers. DOE notes that the equation used to calculate
standby loss in DOE's test method for instantaneous water heaters and
hot water supply boilers (as specified in Exhibit G.2 of ANSI Z21.10.3-
2011) uses two temperature differential terms that both include the
measurement of the mean tank temperature taken during the course of the
test. To calculate the standby loss of CWH equipment, the current
Federal test method requires parameters to be measured that allow for
the calculation of: (1) The amount of energy consumed to maintain the
stored water at the required temperature during standby mode; (2) the
heat lost to the atmosphere from the stored water; and (3) the change
in total heat content of the water heater between the start and the end
of the test. Both the terms described in (2) and (3) are calculated
using the stored water temperature, which are represented in DOE's
current test method by the mean tank temperature measured during the
standby loss test. Instantaneous water heaters and hot water supply
boilers that do not meet DOE's proposed definition for ``storage-type
instantaneous water heater'' (see section III.F of this document) are
generally not equipped with an integral hot water storage tank, but
rather, the stored water is contained within the heat exchanger. Unlike
storage water heaters and storage-type instantaneous water heaters,
these instantaneous water
[[Page 28616]]
heaters and hot water supply boilers generally have water-tube heat
exchangers \17\ and do not store water at a uniform temperature in the
heat exchanger. Due to complex heat exchanger geometries, an accurate
measurement of the mean temperature of water stored within the heat
exchanger is often difficult or impossible to obtain. As a result, DOE
has tentatively concluded that modifications to the standby loss test
method are warranted for instantaneous water heaters and hot water
supply boilers that have a storage capacity of ten gallons or more, but
that do not meet DOE's proposed definition for ``storage-type
instantaneous water heater.'' In this NOPR, DOE proposes a separate
standby loss test procedure in section III.G for flow-activated
instantaneous water heaters, which have no means of burner or heating
element activation unless hot water is drawn. In this section (i.e.,
section III.I), DOE proposes a new standby loss test procedure for
instantaneous water heaters and hot water supply boilers. This proposed
test procedure would only apply to instantaneous water heaters and hot
water supply boilers that do not meet DOE's proposed definitions for
``storage-type instantaneous water heater'' or ``flow-activated
instantaneous water heater.'' The proposed test procedure is also
specified in appendices C and D to subpart G of part 431.
---------------------------------------------------------------------------
\17\ By water-tube heat exchangers, DOE refers to a heat
exchanger where water flows inside heat exchanger tubes and is
heated by an external source of energy.
---------------------------------------------------------------------------
DOE encountered the same issue for flow-activated water heaters and
addressed this problem in the proposed test procedure described in
section III.G. While thermostatically-activated instantaneous water
heaters and hot water supply boilers differ from flow-activated
instantaneous water heaters in their mechanism to initiate burner or
heating element operation, these two kinds of equipment share similar
heat exchanger geometries and designs. In section III.G of this
rulemaking, DOE discusses the responses received from manufacturers on
this issue for the standby loss test method for flow-activated
instantaneous water heaters. In summary, manufacturers suggested that a
measurement of the outlet water temperature could be used as an
approximation of the mean stored water temperature within the heat
exchanger for the purpose of calculating standby loss. Due to the
similarity in heat exchanger design between flow-activated and
thermostatically-activated instantaneous water heaters and hot water
supply boilers, DOE has tentatively concluded that the same rationale
would apply for thermostatically-activated instantaneous water heaters
and hot water supply boilers (i.e., a measurement of the outlet
temperature can be used as a reasonable approximation of the mean
stored water temperature within the heat exchanger for the purpose of
calculating standby loss for thermostatically-activated instantaneous
water heaters and hot water supply boilers). Therefore, DOE proposes to
use the outlet water temperature as measured by the outlet water
temperature sensor, instead of the mean tank temperature, to
approximate the stored water temperature for the purpose of calculating
standby loss for instantaneous water heaters and hot water supply
boilers that do not meet DOE's proposed definition for ``storage-type
instantaneous water heater,'' including flow-activated instantaneous
water heaters.
DOE also considered several other options to calculate or measure
the average stored water temperature (e.g., using the average of the
supply and outlet water temperature, inserting thermocouples inside the
heat exchanger through the outlet port of the water heater, or using
heat transfer equations to back calculate stored water temperature from
the heat exchanger tube wall temperature). DOE has tentatively
concluded that none of the other options considered would provide an
accurate measurement of the average stored water temperature inside the
water heater. Moreover, because of the complex heat exchanger geometry,
there would be significant difficulty involved in attempting to
calculate the average stored water temperature.
DOE is also aware that in many applications, instantaneous water
heaters or hot water supply boilers are used to supply hot water to an
external tank where the water is stored at a fixed temperature. In
these applications, a thermostat is often used to maintain the desired
water temperature in the external tank as part of a recirculation loop.
If the water temperature in the tank falls below the set point, then
the thermostat directs the water heater to cycle on, and the
recirculation pump circulates water throughout the loop, withdrawing
water from the tank, and resupplying heated water back into the tank.
While reviewing the standby loss test procedure for its applicability
to thermostatically-activated instantaneous water heaters and hot water
supply boilers, DOE considered the option of specifying an external
UFHWST with specific characteristics (e.g., insulation, storage volume)
to be able to calculate the mean tank temperature. However, DOE has
tentatively decided not to use this approach to conduct the standby
loss test for thermostatically-activated instantaneous water heaters
because it would also include the standby loss that occurs in the
external tank and therefore, would not be representative of the water
heater itself. Therefore, DOE has decided not to use an external tank
to measure the mean tank temperature to conduct the standby loss test
for thermostatically-activated instantaneous water heaters and hot
water supply boilers.
Based on the discussion above, DOE proposes the following test
procedure for determining the standby loss of instantaneous water
heaters and hot water supply boilers (except for those that meet the
proposed definition of a ``storage-type instantaneous water heater''
and ``flow-activated instantaneous water heater''). This proposal
includes some language from Annex E.2 of ANSI Z21.10.3-2015.
The proposed standby loss test method for instantaneous water
heaters and hot water supply boilers (except those meeting the
definition of ``storage-type instantaneous water heater'' and ``flow-
activated instantaneous water heater'') can be started immediately
after the thermal efficiency test, using the same test set-up and test
conditions. Otherwise, if the standby loss test is conducted
separately, one would install the water heater as per Figure III.4 in
section III.H of this rulemaking (Figure 4 in appendix C to subpart G
of part 431) and section 2 of appendix C or D (as applicable) to
subpart G of part 431 to set up the water heater for testing. As
discussed in section III.H, DOE proposes required locations for
temperature-sensing instrumentation and water valves for all
instantaneous water heaters and hot water supply boilers, including
flow-activated instantaneous water heaters, but excluding storage-type
instantaneous water heaters. For water heaters with multiple supply or
outlet water connections entering the water heater jacket, apply the
outlet water temperature sensor and water valves placement provisions
proposed in section III.H to each pipe connection entering or leaving
the water heater. The representative value of the outlet water
temperature used for the standby loss calculations is obtained by
taking the average of the water temperatures measured at each water
connection leaving the water heater jacket.
DOE proposes that the test be conducted as follows:
Once the water heater is set up, open the flow valves, start the
water pump, open the gas supply valves (as
[[Page 28617]]
applicable), and then initiate the ignition process. After the water
heater starts with the initiation of burner or heating element
operation, monitor the supply and outlet water temperatures. Adjust the
water flow rate in such a way that the outlet water temperature reaches
a temperature of 70[emsp14][deg]F 2[emsp14][deg]F above
the supply water temperature. Once this temperature is achieved,
maintain the flow rate and keep monitoring the outlet water
temperature. After the outlet water temperature has remained constant
with no variation of more than 2[emsp14][deg]F over a 3-minute period,
turn off the water supply and outlet valves and, if necessary, the
water pump. The fuel supply must be kept on for the entire duration of
the test for gas-fired and oil-fired equipment. After the first cut-
out, allow the water heater to remain in standby mode until the next
cut-out.
At this point, start the clock and record the initial outlet water
and ambient room temperatures. Keep recording the outlet water
temperature, the ambient room temperature, the time elapsed from the
start of the test, the electricity consumption, and the fuel
consumption at an interval of 30 seconds (as proposed in this
rulemaking and discussed in section III.B) using a data acquisition
system.
The duration of this test will be the earlier of: (1) The first
cut-out that occurs after 24 hours or (2) 48 hours.
At the conclusion of the test, record the total fuel flow,
electricity consumption, the final ambient room temperature, the time
duration in hours rounded to the nearest one hundredth of an hour, and
the final outlet water temperature.
Use the equation below to calculate the standby loss in terms of
percent of total heat content per hour.
[GRAPHIC] [TIFF OMITTED] TP09MY16.272
Where,
[Delta]T3 = Average value of outlet water temperature
minus the average value of the ambient room temperature, expressed
in [deg]F
[Delta]T4 = Final outlet water temperature measured at
the end of the test minus the initial outlet water temperature
measured at the start of the test, expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons
Et = Thermal efficiency of the water heater. For electric
water heaters with immersed heating elements use 98 percent.
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
t = Total duration of the test in hours
Cs = Correction applied to the heating value of a gas H,
when it is metered at temperature and/or pressure conditions other
than the standard conditions upon which the value of H is based.
Cs is not applicable to oil-fired equipment.
Qs = Total fuel flow as metered for gas-fired and oil-
fired equipment, expressed in ft\3\ (gas) or lb (oil).
H = Higher heating value of gas, expressed in Btu/ft\3\ (gas) or
Btu/lb (oil)
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the heat
content of the stored water above room temperature
The standby loss expressed in Btu per hour must be calculated as
follows: SL (Btu per hour) = S (% per hour) x 8.25 (Btu/gal-[deg]F) x
Measured Volume (gal) x 70 (degrees F).
Issue 17: DOE requests comment on the proposed test procedure for
instantaneous water heaters and hot water supply boilers (except those
meeting the proposed definition of ``storage-type instantaneous water
heater'' and ``flow-activated instantaneous water heater''). DOE also
requests feedback on its tentative decision to use the outlet water
temperature instead of the mean tank temperature or stored water
temperature to conduct the standby loss test. Further, DOE requests
suggestions on methods or approaches that can be used to measure the
stored water temperature accurately.
J. Test Procedure for Rating Commercial Heat Pump Water Heaters
In the February 2014 RFI, DOE raised an issue with regards to
implementing a new test procedure for commercial heat pump water
heaters (CHPWHs). 79 FR 10999, 11003 (Feb. 27, 2014). Currently, DOE
does not have a test procedure for commercial heat pump water heaters
(although a section is reserved at 10 CFR 431.107). Additionally, DOE
does not currently have a definition for ``commercial heat pump water
heater,'' as would help classify such units. Therefore, DOE proposes
the following definition for commercial heat pump water heaters that
includes air-source, water-source, and direct geo-exchange CHPWHs.
Commercial heat pump water heater (CHPWH) means a water heater that
uses a refrigeration cycle, such as vapor compression, to transfer heat
from a low-temperature source to a higher-temperature sink for the
purpose of heating potable water, and has a rated electric power input
greater than 12 kW. Such equipment includes, but is not limited to,
air-source heat pump water heaters, water-source heat pump water
heaters, and direct geo-exchange heat pump water heaters.
Issue 18: DOE requests comment on its proposed definition for
``commercial heat pump water heater.''
DOE is aware that ANSI/ASHRAE Standard 118.1-2012 (``ASHRAE 118.1-
2012''), Method of Testing for Rating Commercial Gas, Electric, and Oil
Service Water-Heating Equipment is used as an industry test method for
CHPWHs. ASHRAE 118.1-2012 includes several test methods, including a
method for determining coefficient of performance (COPh),
standby loss for commercial heat pump water heaters, and cooling output
of air-source CHPWHs. DOE considered this test procedure for adoption
as the Federal test method for CHPWHs. In addition to ASHRAE 118.1-
2012, DOE is also aware of another relevant industry standard, the
ANSI/AHRI Standard 1300 (I-P)-2013 (``AHRI 1300''), Performance Rating
of Commercial Heat Pump Water Heaters. AHRI 1300 specifies rating
conditions (e.g., entering water temperature, leaving water
temperature, and other evaporator side rating conditions) for testing
CHPWHs, but it references ASHRAE 118.1-2012 for the actual procedure to
conduct the test. DOE considered the rating conditions specified in
AHRI 1300 for developing a test procedure for CHPWHs. In the February
2014 RFI, DOE requested public comment on adopting an appropriate test
procedure for CHPWHs. DOE sought comment on both of the aforementioned
industry test methods and on whether any modifications would be needed
for adopting them as the Federal test method. 79 FR 10999, 11003 (Feb.
27, 2014).
DOE received several comments from interested parties in response
to this issue. Bradford White supported the use
[[Page 28618]]
of AHRI 1300 as an appropriate test method for rating CHPWHs. (Bradford
White, No. 8 at p. 2) AHRI commented that the efficiency of CHPWHs
should be measured at two rating conditions. AHRI also supported the
use of AHRI 1300 as the test procedure to measure efficiency of CHPWHs,
and HTP stated that it support AHRI's position on this topic. (AHRI,
No. 2 at p. 4; HTP, No. 5 at p. 5) Rheem also supported the use of AHRI
1300 as the rating standard. In addition, Rheem supported any
modifications to AHRI 1300 that may be required to address issues
identified by industry during testing. (Rheem, No. 3 at p. 2) APPA also
supported the use of AHRI 1300 for testing CHPWHs and stated that the
AHRI 1300 standard references ASHRAE 118.1, which represents an ANSI-
approved consensus of multiple stakeholders. (APPA, No. 6 at p. 2) EEI
also supported the use of AHRI 1300 for rating CHPWHs. Both APPA and
EEI expressed support for the adoption of an industry test procedure to
minimize cost by avoiding duplicative testing standards. (APPA, No. 6
at p. 2; EEI, No. 9 at p. 2) A.O. Smith recommended the use of ASHRAE
118.1-2012 and stated that ASHRAE 118.1-2012 is being revised to
harmonize its rating conditions with the conditions in AHRI 1300. (A.O.
Smith, No. 7 at pp. 2-3)
The Joint Advocates also commented that they strongly support DOE's
efforts to adopt a consensus test procedure standard for CHPWHs. To
assist DOE in the rulemaking, the Joint Advocates posed several
questions that may influence DOE's direction for this rulemaking. The
Joint Advocates asked whether there are any international standards
that have lessons for U.S. practice. (Joint Advocates, No. 4 at pp. 2-
3) DOE reviewed the Collaborative Labeling and Appliance Standards
Program's (CLASP's) Global Standards and Labeling Database \18\ and
determined that no other country has adopted efficiency standards for
CHPWHs. Additionally, DOE reviewed the Super-efficient Equipment and
Appliance Deployment (SEAD) report on potential for harmonization of
international standards for heat pump water heaters.\19\ This report
primarily discussed residential heat pump water heaters and was not
useful in the context of this commercial rulemaking.
---------------------------------------------------------------------------
\18\ ``CLASP's Global S&L Database.'' CLASP (Dec. 7, 2015)
(Available at: http://www.clasp.ngo/ResourcesTools/Tools/SL_Search).
\19\ Additional information on international standards for HPWHs
can be found at: http://tinyurl.com/jnx79ay.
---------------------------------------------------------------------------
The Joint Advocates asked how first-hour supply capability is
treated as a capacity measure for CHPWHs. (Joint Advocates, No. 4 at
pp. 2-3) DOE acknowledges that delivery capacity of CWH equipment,
including CHPWHs, is an important metric for selection and sizing of
equipment. However, DOE does not believe such a capacity measure is
needed in its test procedure for energy efficiency, as information
regarding capacity is already typically readily available in
manufacturer literature.
The Joint Advocates asked about the potential impacts of ambient
conditions on the test procedure. (Joint Advocates, No. 4 at pp. 2-3)
In response, DOE conducted exploratory tests on different CHPWH units
at the different rating conditions specified in ASHRAE 118.1-2012 and
AHRI 1300. DOE considered the information and results gathered from
these tests in the development of the proposed test procedure for
CHPWHs. The exploratory tests are discussed in more detail later in
this section.
The Joint Advocates raised the issue of the need to consider the
capabilities of different refrigerants to achieve temperature rise that
is required for commercial applications (i.e., outlet water temperature
of ~170[emsp14][deg]F). (Joint Advocates, No. 4 at pp. 2-3) DOE notes
that most of the CHPWH models available on the market use R-134a, R-
410A or R-22 as refrigerants. Further, DOE notes that industry test
standards (e.g., ASHRAE 118.1-2012 and AHRI 1300) specify an outlet
water temperature of 120[emsp14][deg]F for testing of heat pump water
heaters, and do not differentiate based on type of refrigerant used.
DOE has found in examining CHPWHs, that an outlet water temperature of
120[emsp14][deg]F is typical and readily achievable in applications
that would be suitable for a CHWPH, regardless of refrigerant type.
Based on the foregoing, DOE has tentatively decided not to provide
different outlet water temperature conditions based on the type of
refrigerant being used.
The Joint Advocates suggested that DOE should consider a different
requirement such as maximum rated temperature instead of a constant
test temperature. (Joint Advocates, No. 4 at pp. 2-3) DOE's proposed
test procedure for CHPWHs includes a provision allowing units that are
unable to meet the outlet water temperature at low entering water
temperatures to be tested using a higher supply temperature. These
provisions are discussed in greater detail later on in this section.
The Joint Advocates asked whether the cooled evaporator air could
be used for cooling spaces and whether the energy value of this benefit
could be included. (Joint Advocates, No. 4 at pp. 2-3) DOE appreciates
that in some sites, cool air rejected from the evaporator coil may
provide an ancillary benefit by providing additional space cooling.
However, DOE does not propose to include a methodology to measure the
cooling performance of a commercial heat pump water heater. DOE finds
that such a methodology would be overly burdensome to manufacturers in
relation to the uncertain benefit provided to commercial consumers.
In addition, the Joint Advocates expressed their goals for the
CHPWH standard as: (1) Allowing fair comparison between products and
(2) giving contractors enough information to help customers make
informed decisions. According to the Joint Advocates, CHPWHs will
require a single metric to be useful and have suggested a blend of the
current metrics as a single rating parameter. (Joint Advocates, No. 4
at pp. 2-3) Although DOE proposes a test procedure for CHPWHs in this
NOPR, the scope of this rulemaking does not include amending energy
conservation standards for CHPWHs. In this NOPR, DOE only proposes a
test procedure that manufacturers can use to rate their products,
without a requirement to certify COPh ratings to DOE. In its
analysis for this NOPR, DOE considered whether the proposed test
procedures for all kinds of CHPWHs would allow for fair comparison
between products. Specifically, DOE reviewed and proposes to
incorporate by reference certain sections of relevant industry test
methods to ensure DOE's test procedure is consistent with industry-
accepted test methods. DOE also conducted investigative testing of
several air-source CHPWHs from different manufacturers to verify the
appropriateness of the proposed test procedure and the consistency of
results. With regards to the metric, DOE notes that the industry test
standards (ASHRAE 118.1-2012 and AHRI 1300) use the coefficient of
performance (COP) as the energy efficiency metric for rating CHPWHs. To
ensure consistency with these industry test standards, DOE has
tentatively decided to use the same energy efficiency metric (COP) for
rating CHPWHs.
The second supplemental comment from AHRI in response to the
February 2014 RFI includes recommended rating conditions for testing
several kinds of CHPWHs. (AHRI (2015), No. 13, pp. 1-2) AHRI
recommended four categories of CHPWHs based on the heat source (i.e.,
air-source, direct geo-exchange, indoor water-source, and ground water-
source) with one set of rating conditions
[[Page 28619]]
for each category. (AHRI (2015), No. 13 at pp. 1-2) The AHRI-
recommended rating conditions that are specified in their comments are
shown in Table III-2:
Table III-2--AHRI-Recommended Classifications and Rating Conditions for
CHPWHs \20\
------------------------------------------------------------------------
Classification based on heat source Recommended rating conditions
------------------------------------------------------------------------
Air-source commercial heat pump water Entering water temperature: 110
heater. [deg]F.
Entering air conditions: 80.6
[deg]F dry bulb and 71.2
[deg]F wet bulb.
Direct geo-exchange commercial heat Entering water temperature: 110
pump water heater. [deg]F.
Evaporator refrigerant
temperature: 32 [deg]F.
Indoor water-source commercial heat Entering water temperature: 110
pump water heater. [deg]F.
Evaporator entering water
temperature: 68 [deg]F.
Ground water-source commercial heat Entering water temperature: 110
pump water heater. [deg]F.
Evaporator entering water
temperature: 50 [deg]F.
------------------------------------------------------------------------
DOE reviewed AHRI's comments carefully and assessed whether the
recommended rating conditions for CHPWHs would sufficiently cover the
types of units that are available on the market. As indicated in Table
III-2, AHRI recommended separate rating conditions for indoor water-
source CHPWHs and ground water-source CHPWHs, despite the fact that
both utilize water or another liquid as the evaporator heat source. DOE
sees merit in having separate rating conditions for indoor water-source
and ground water-source units, because the temperature of water
entering the evaporator would be different for each application.
However, for the purpose of testing and rating CHPWHs, both indoor
water-source CHPWHs and ground water-source CHPWHs can be tested using
the same test procedure but with different rating conditions.
---------------------------------------------------------------------------
\20\ The AHRI recommended classifications and rating conditions
for CHPWHs can be found in their comments at: http://www.regulations.gov/#!documentDetail;D=EERE-2014-BT-TP-0008-0013.
---------------------------------------------------------------------------
ASHRAE 118.1-2012 includes a similar classification with separate
test procedures for air-source, direct geo-exchange, and water-source
CHPWHs. The test procedure for water-source CHPWHs in ASHRAE 118.1-2012
applies to both indoor water-source CHPWHs and ground water-source
CHPWHs. After considering the applications and characteristics of the
different kinds of CHPWHs and the classification used in ASHRAE 118.1-
2012, DOE proposes separate test procedures for air-source, direct geo-
exchange, and water-source CHPWHs. The proposed test procedure for
water-source CHPWHs would be used to rate both ground water-source and
indoor water-source models with different rating conditions for each
category.
To differentiate the four categories of CHPWHs from each other, DOE
proposes to add definitions for ``Air-source commercial heat pump water
heater'', ``Direct geo-exchange commercial heat pump water heater'',
``Indoor water-source commercial heat pump water heater'', and ``Ground
water-source commercial heat pump water heater,'' as set out in the
regulatory text at the end of this document.
Issue 19: DOE requests comment on the proposed categories of CHPWHs
and related definitions. In particular, DOE requests comments on CHPWH
heat sources that are currently available for commercial applications.
To develop new test procedures for all four categories of CHPWHs,
DOE reviewed both ASHRAE 118.1-2012 and AHRI 1300. As noted earlier,
AHRI 1300 only provides rating conditions and references ASHRAE 118.1-
2012 for the actual test method. ASHRAE 118.1-2012 is an industry test
method used to rate gas-fired, electric, and oil-fired CWH equipment.
For the purpose of testing, ASHRAE 118.1-2012 classifies CHPWHs into
two types: (1) ``Type IV''--equipment that can be operated without
requiring a connection to a storage tank; and (2) ``Type V''--equipment
that requires connection to a storage tank for operation. ASHRAE 118.1-
2012 specifies separate test methods to rate the two types of
equipment. The test procedure described in ASHRAE 118.1-2012 for Type V
units requires the unit to be connected to a tank that is either
supplied by the manufacturer along with the unit or is specified by the
manufacturer. However, after reviewing product literature, DOE notes
that generally, CHPWH manufacturers neither supply a storage tank with
the equipment, nor specify a tank appropriate for that equipment. The
ASHRAE 118.1-2012 test procedure does not include a test method for
Type V units for which an appropriate tank is neither supplied nor
specified by the manufacturer. Without connecting an appropriate tank,
Type V equipment cannot be tested using the Type V equipment test
procedure as specified in ASHRAE 118.1-2012.
DOE considered establishing a ``standard'' tank for rating the
energy efficiency of Type V units that are not shipped with a tank and
for which manufacturers do not specify the tank to be used. However,
DOE tentatively determined that testing and rating a CHPWH by
connecting it with a separately supplied tank could be an unfair
representation of the actual rating of the unit itself since the
efficiency of the system is highly dependent on the characteristics of
the tank. Further, different CHPWHs may be designed for use with tanks
having different characteristics. Theoretically, the combined
efficiency rating of a CHPWH unit when operated along with the tank
would be lower than the actual rating of that CHPWH unit alone, because
the addition of a tank would allow for heat loss through the tank
jacket and piping. Also, there may be inconsistencies in selecting
tanks used for efficiency testing if manufacturers do not supply or
specify an appropriate tank for the CHPWH units. This inconsistency
could lead to energy savings smaller than expected for commercial
consumers if CHPWHs are tested with storage tanks more efficient than
those that those commercial consumers use.
Considering these issues associated with testing a CHPWH unit with
an external tank connected to it, DOE explored the possibility of
formulating a new test method to test all CHPWH units as Type IV
equipment (i.e., without connecting a hot water storage tank while
testing). In order to verify the applicability of the Type IV test to
all CHPWH units, DOE selected three air-source CHPWH units available on
the market and tested them using the test procedure specified in ASHRAE
118.1-2012. DOE tested the units at six different rating conditions
specified for air-source CHPWHs by both ASHRAE
[[Page 28620]]
118.1-2012 and AHRI 1300, as shown in Table III-3. The units that were
chosen for testing were purchased from different manufacturers and had
varying levels of heating capacities (100,000 Btu/h; 30,000 Btu/h; and
275,000 Btu/h). All of these units had an internal pump fitted within
the unit, so no external pump was required to supply inlet water to the
condenser of the heat pump.
The test procedure for air-source CHPWHs as specified in ASHRAE
118.1-2012 requires the CHPWH to be set up according to Figure 5 of
that test standard. The water flow rate through the unit is adjusted in
such a way that the outlet water temperature is maintained at
120[emsp14][deg]F 5[emsp14][deg]F with no variation of
more than 2[emsp14][deg]F over a three-minute period. DOE conducted the
tests under six different rating conditions, which consist of three
different evaporator entering air temperatures and two supply water
temperature conditions. In all, DOE conducted six tests on each CHPWH
unit. These test conditions are shown in Table III-3:
Table III-3--Rating Conditions for Testing Commercial Heat Pump Water Heaters
----------------------------------------------------------------------------------------------------------------
Evaporator entering air Condenser
temperature [[deg]F] entering water
Rating conditions -------------------------------- temperature
Dry bulb Wet bulb [[deg]F]
----------------------------------------------------------------------------------------------------------------
1............................................................... * 95 * 75 70
2............................................................... 80.6 71.2 70
3............................................................... 50 44.3 70
4............................................................... * 95 * 75 * 110
5............................................................... 80.6 71.2 * 110
6............................................................... 50 44.3 * 110
----------------------------------------------------------------------------------------------------------------
* Rating conditions which are included in ANSI/ASHRAE 118.1-2012. (Note, all rating conditions in this table are
included in AHRI 1300-2013.)
The results obtained from these tests indicate that not all the
units were capable of achieving an outlet water temperature of
120[emsp14][deg]F 5[emsp14][deg]F. The 30,000 Btu/h unit
was the only unit capable of delivering the required outlet water
temperature for all six rating conditions. For rating conditions 1, 2,
and 3, the flow rate for the 30,000 Btu/h unit had to be sharply
reduced to achieve the high temperature rise from a supply water
temperature of 70[emsp14][deg]F to outlet water temperature of
120[emsp14][deg]F 5[emsp14][deg]F. However, for the rating
conditions 4, 5, and 6, the unit successfully delivered water at a
temperature of 120[emsp14][deg]F 5[emsp14][deg]F at the
manufacturer's specified flow rate.
The 100,000 Btu/h unit was not able to achieve an outlet water
temperature of 120[emsp14][deg]F 5[emsp14][deg]F at rating
conditions 1 and 2. Moreover, the unit was unable to operate at rating
conditions 3 and 6 (evaporator entering air dry bulb temperature of
50[emsp14][deg]F) due to low ambient temperature conditions. When the
unit was tested at rating conditions 4 and 5, the unit was successful
at achieving the 120[emsp14][deg]F 5[emsp14][deg]F outlet
water temperature at the manufacturer-rated water flow rate.
The 275,000 Btu/h unit was capable of achieving the required
120[emsp14][deg]F 5[emsp14][deg]F outlet water temperature
when tested at rating conditions 1 and 2 with the manufacturer's rated
water flow rate. However, the unit did not achieve the required outlet
water temperature for any of the other rating conditions. A possible
reason for this is the low ambient temperature resulting in lower heat
being utilized by the heat pump. For rating conditions 4, 5, and 6
where the supply water temperature is maintained at 110[emsp14][deg]F,
the outlet water temperature exceeded 120[emsp14][deg]F
5[emsp14][deg]F. The water flow rate for these conditions was at the
manufacturer's rated flow rate, and the unit's design did not allow the
flow rate to be increased above that value.
Based on these tests, two conclusions can be drawn. First, rating
conditions 3 and 6, representing an evaporator entering air dry bulb
temperature of 50[emsp14][deg]F, were not achievable for two of the
tested units, (i.e., the 100,000 Btu/h unit and the 275,000 Btu/h
unit). One of the reasons for this is the reduced temperature
difference between the refrigerant saturation temperature and the
evaporator entering air temperature, which severely limits the
evaporator performance. Second, the lower heating capacity units
(30,000 Btu/h and 100,000 Btu/h) were able to achieve the required
outlet water temperature of 120[emsp14][deg]F
5[emsp14][deg]F at the manufacturer's rated supply water flow rate when
the supply water temperature was set to 110[emsp14][deg]F, whereas the
larger heating capacity unit (275,000 Btu/h) was able to meet the
required outlet water temperature condition at the manufacturer's rated
flow rate when the supply water temperature was set to
70[emsp14][deg]F. This indicates that some units are sized to achieve a
low water temperature rise, while others are sized to achieve a higher
water temperature rise.
On the basis of these exploratory tests, DOE was able to determine
applicability of the test procedure described for ``Type IV'' units in
ASHRAE 118.1-2012 to air-source CHPWH units. Based on the results and
the discussion above, DOE has tentatively concluded that the method of
test described for ``Type IV'' units in ASHRAE 118.1-2012 can be used
to test air-source CHPWHs but with certain modifications. These
proposed modifications include establishing: (1) A single evaporator
air entering rating condition with a dry bulb temperature of
80.6[emsp14][deg]F 1[emsp14][deg]F and a wet bulb
temperature of 71.2[emsp14][deg]F 1[emsp14][deg]F; (2) a
supply water temperature of 70[emsp14][deg]F
1[emsp14][deg]F (or 110[emsp14][deg]F 1[emsp14][deg]F,
only if the required outlet water temperature condition is not achieved
while testing at a supply water temperature of 70[emsp14][deg]F 1[emsp14][deg]F).
DOE did not conduct exploratory tests for other categories of
CHPWHs (i.e., direct geo-exchange, indoor water-source, and ground
water-source CHPWHs). As discussed previously, AHRI's initial comment
recommended using AHRI 1300 for rating CHPWHs (which utilizes ASHRAE
118.1-2012 as the actual procedure), and AHRI's supplemental comment
suggested rating conditions appropriate for direct geo-exchange, indoor
water-source, and ground water-source CHPWHs. As DOE has not identified
any other industry test method applicable to CHPWHs, DOE has
tentatively determined to use the test method for ``Type IV'' equipment
specified in ASHRAE 118.1-2012 with rating conditions recommended by
AHRI (Table III-2) for testing the energy efficiency of direct geo-
exchange, indoor water-source, and ground water-source CHPWHs.
Specifically, DOE proposes that direct
[[Page 28621]]
geo-exchange CHPWHs be tested using the ASHRAE 118.1-2012 test
procedure for ``Type IV'' direct geo-exchange heat pump water heaters
with an entering water temperature of 110[emsp14][deg]F and evaporator
refrigerant temperature of 32[emsp14][deg]F. DOE proposes indoor water-
source and ground water-source CHPWHs be tested according to the ASHRAE
118.1-2012 test procedure for ``Type IV'' water-source heat pump water
heaters, with an entering water temperature of 110[emsp14][deg]F and
evaporator entering water temperature of 68[emsp14][deg]F and
50[emsp14][deg]F for indoor water-source and ground water-source
CHPWHs, respectively.
ASHRAE 118.1-2012 provides several test procedure metrics for
measuring energy efficiency (e.g., Coefficient of performance with full
input rating (section 9.1.1 of ASHRAE 118.1), Coefficient of
performance with reduced input rating (9.1.2 of ASHRAE 118.1), standby
energy consumption (section 9.2 of ASHRAE 118.1), and cooling output
(section 9.3 of ASHRAE 118.1)). Coefficient of performance refers to
the ratio of the useful heat gained by the water (in Btu/h) to the
electric power consumed by the unit (in Btu/h). For the current
rulemaking, DOE proposes to use the test procedure for measuring
coefficient of performance for full input rating. DOE also proposes to
define ``coefficient of performance'' as set out in the regulatory text
at the end of this document.
As previously noted, DOE's proposed test procedure for rating
CHPWHs would incorporate by reference certain relevant sections of
ASHRAE 118.1-2012. The succeeding paragraphs highlight various sections
that are relevant to testing units of all four categories of CHPWHs.
DOE proposes that the instrumentation required for the new test
procedure would be as described in section 6 of ASHRAE 118.1. Further,
DOE proposes that the test set-up, piping, and temperature-sensing
locations be as described in sections 7.1, 7.2.1, 7.3.2, 7.3.3, 7.5,
and 7.6 of that industry standard for testing Type IV equipment. DOE
also proposes to incorporate subsections 7.7.1 to 7.7.6 with the
exclusion of section 7.7.5 of ASHRAE 118.1-2012. Section 7.7.5 of
ASHRAE 118.1-2012 contains special requirements for testing a heat pump
water heater for measurement of space cooling. Section 7.7.7 of ASHRAE
118.1-2012 refers to Table 2 of the same test standard, which provides
values for supply (or entering) water temperatures for testing CHPWHs.
DOE has tentatively decided not to directly adopt section 7.7.7 of
ASHRAE 118.1-2012 and instead proposes to adopt the following
provisions to replace section 7.7.7 as follows:
Modifications for Water-Source CHPWHs and Direct Geo-Exchange CHPWHs
DOE proposes to test direct geo-exchange, indoor water-source, and
ground water-source CHPWHs with a nominal entering water temperature of
110[emsp14][deg]F instead of the temperature specified in Table 2
referenced by section 7.7.7 of ASHRAE 118.1.
Modifications for Air-Source CHPWHs
DOE proposes that air-source CHPWH equipment be tested with a
supply water temperature of 70[emsp14][deg]F
1[emsp14][deg]F. If the required outlet water temperature condition
(specified in section 8.7.2 of ASHRAE 118.1-2012) is not met while
testing the unit at 70[emsp14][deg]F 1[emsp14][deg]F, only
then should the supply water temperature be provided at
110[emsp14][deg]F 1[emsp14][deg]F. DOE proposes to use the
following steps for setting the supply water temperature that would be
applicable to the air-source CHPWH unit being tested:
(1) Set the supply water temperature at 70[emsp14][deg]F 1[emsp14][deg]F and the water flow rate to the rated pump flow
rate and start operating the unit. Measure the outlet water temperature
at this flow rate to check if an outlet water temperature of
120[emsp14][deg]F 5[emsp14][deg]F is achieved as specified
in section 8.7.2 of ASHRAE 118.1-2012. If the outlet water temperature
is maintained at this condition (i.e., at a temperature of
120[emsp14][deg]F 5[emsp14][deg]F and with no variation of
more than 2[emsp14][deg]F over a three-minute period), then conduct the
test as per section 9.1.1 of ASHRAE 118.1-2012.
(2) If the outlet water temperature condition is not met, then
adjust the flow rate in order to meet the required outlet water
temperature condition as per section 8.7.2 of ASHRAE 118.1-2012.
Measure the outlet water temperature at the adjusted flow rate to check
if an outlet water temperature of 120[emsp14][deg]F
5[emsp14][deg]F is achieved as specified in section 8.7.2 of ASHRAE
118.1-2012. If the outlet water temperature is maintained at this
condition (i.e., at a temperature of 120[emsp14][deg]F
5[emsp14][deg]F and with no variation of more than 2[emsp14][deg]F over
a three-minute period), then conduct the test as per section 9.1.1 of
ASHRAE 118.1-2012.
(3) If, after adjusting the flow rate within the range that is
achievable by the pump, the equipment is unable to operate or deliver
the required outlet water temperature, then reset the flow rate to the
rated pump flow rate and change the supply water temperature to
110[emsp14][deg]F 1[emsp14][deg]F. Measure the outlet
water temperature at the rated pump flow rate to determine whether the
outlet water temperature requirement is met as per section 8.7.2 of
ASHRAE 118.1-2012. If the outlet water temperature is maintained at
this condition (i.e., at a temperature of 120[emsp14][deg]F 5[emsp14][deg]F and with no variation of more than
2[emsp14][deg]F over a three-minute period), then conduct the test as
per section 9.1.1 of ASHRAE 118.1-2012.
(4) If the outlet water temperature condition is not met, then
adjust the flow rate in order to meet the required outlet water
condition as per section 8.7.2 of ASHRAE 118.1-2012. Measure the outlet
water temperature at the adjusted flow rate to check if an outlet water
temperature of 110[emsp14][deg]F 1[emsp14][deg]F is
achieved as specified in section 8.7.2 of ASHRAE 118.1-2012. If the
outlet water temperature is maintained at this condition (i.e., at a
temperature of 120[emsp14][deg]F 5[emsp14][deg]F and with
no variation of more than 2[emsp14][deg]F over a three-minute period),
then conduct the test as per section 9.1.1 of ASHRAE 118.1-2012.
(5) If the outlet water temperature condition cannot be met, then a
test procedure waiver is necessary to specify an alternative set of
test conditions.
DOE proposes to retain Table 3 of ASHRAE 118.1-2012, which provides
tolerances of different parameters (e.g., water temperatures, water
flow rates) and, sections 7.7.7.1 and 7.7.7.2 of ASHRAE 118.1-2012 that
specifies requirements for measurement of water flow and temperature.
If the CHPWH is equipped with a thermostat that controls the throttling
valve, then use section 7.7.7.3 of ASHRAE 118.1-2012 to set up the
thermostat. DOE also proposes to use sections 8.2.1 and 8.7.2 of ASHRAE
118.1-2012 for specifying electrical supply and outlet water
temperature requirements, respectively. The method of test would be as
per the test procedure specified in section 9.1.1 of ASHRAE 118.1. The
rating conditions in ASHRAE 118.1-2012 are contained tables B-1, B-2,
and B-3 of appendix B5 of the industry test standard, and referenced
from section 9.4.1 of that test method. Rather than use the rating
conditions specified in ASHRAE 118.1-2012, DOE proposes to use a single
rating condition for each category of CHPWHs as specified in Table III-
4:
[[Page 28622]]
Table III-4--Proposed Rating Conditions for CHPWHs
------------------------------------------------------------------------
Evaporator side Condenser side
Category of CHPWH rating conditions rating conditions
------------------------------------------------------------------------
Air-source commercial heat Evaporator entering Entering water
pump water heater. air conditions: temperature: 70
Dry bulb: 80.6 [deg]F
[deg]F 1 [deg]F. Vary
1 [deg]F and. water flow rate (if
Wet bulb: 71.2 needed) to achieve
[deg]F the outlet water
1 [deg]F. temperature as
specified in
section 8.7.2 of
ASHRAE 118.1-2012.
If required outlet
water temperature
as specified in
section 8.7.2 of
ASHRAE 118.1-2012
is not met even
after varying the
flow rate, then
change the
condenser entering
water temperature
to 110 [deg]F 1 [deg]F.
Vary flow rate to
achieve the
conditions in
section 8.7.2 of
ASHRAE 118.1-2012.
Direct geo-exchange Evaporator Entering water
commercial heat pump water refrigerant temperature: 110
heater. temperature: 32 [deg]F
[deg]F 1 [deg]F.
1 [deg]F.
Indoor water-source Evaporator entering Entering water
commercial heat pump water water temperature: temperature: 110
heater. 68 [deg]F
minus> 1 [deg]F. 1 [deg]F.
Ground water-source Evaporator entering Entering water
commercial heat pump water water temperature: temperature: 110
heater. 50 [deg]F
minus> 1 [deg]F. 1 [deg]F.
------------------------------------------------------------------------
To calculate the final COPh value, DOE proposes to use
section 10.3.1 of ASHRAE 118.1-2012.
To further assess the new test method, DOE conducted a second round
of experimental testing on the 100,000 Btu/h CHPWH unit. In this round,
the test was carried out exactly as per the proposed test procedure
specified in appendix F to subpart G of part 431 and proposed in this
section of the NOPR. DOE tested the unit with evaporator entering air
temperatures specified in appendix F to subpart G of part 431 (also
specified in Table III-4). As proposed, the unit was first tested with
a supply water temperature of 70[emsp14][deg]F
1[emsp14][deg]F. At these rating conditions, the unit was unable to
achieve an outlet water temperature of 120[emsp14][deg]F
5[emsp14][deg]F, even after varying the supply water flow rate. The
supply water temperature was then re-adjusted to 110[emsp14][deg]F
1[emsp14][deg]F. At this temperature, the unit was
successful in delivering and maintaining an outlet water temperature of
120[emsp14][deg]F 5[emsp14][deg]F with no variation of
more than 2[emsp14][deg]F over a three-minute duration. Results show
that the COPh value obtained in the second round of testing
in reasonably close agreement between the COPh measured in
the first round of testing, indicative of the repeatability and
practicability of the proposed test procedure.
Issue 20: DOE requests comment on all aspects of the proposed test
procedure for commercial heat pump water heaters, and in particular,
the proposal to test all units without a storage tank. DOE also invites
comment on its recommended rating conditions, particularly the supply
water temperatures for air-source commercial heat pump water heaters.
K. Fuel Input Rate
In DOE's existing regulations, equipment classes and the standards
that apply to them are determined partly on the basis of the input
capacity of the CWH equipment. However, several terms are used in the
existing DOE test procedures and energy conservation standards to
describe the capacity of the CWH equipment, each of which is derived
from the maximum rated fuel input rate to the CWH equipment. For
example, the existing DOE test procedure for CWH equipment at 10 CFR
431.106 uses the term ``hourly Btu input rate'' to describe the
measured input rate during the test and ``manufacturer's specified
input rate'' as the value to which the measured input rate should be
compared. The energy conservation standards for CWH equipment at 10 CFR
431.110 use the term ``nameplate input rate,'' which is intended to
mean the same thing as ``manufacturer's specified input rate.'' While
DOE's test procedure for oil-fired CWH equipment requires the hourly
Btu input rate to be within 2 percent of the manufacturer's
specified input rate, no procedure is included for measuring the input
rate.
To clarify standardize terminology throughout its regulations for
CWH equipment and to determine the appropriate equipment class for CWH
equipment, DOE proposes to define the term ``fuel input rate'' as set
out in the regulatory text at the end of this document.
DOE proposes to use this term in the division of equipment classes
and applicable testing provisions to determine the fuel input rate.
Manufacturers would be required to measure the fuel input rate during
certification testing and use the mean of the measured values, after
applying the applicable rounding provisions (discussed later in this
section), in certification reports pursuant to 10 CFR 429.44(c)(2). DOE
also notes that, for CWH equipment certified using an AEDM, the AEDM
would be used to determine the fuel input rate and the same rounding
provisions would apply. DOE believes it is critical to clarify how the
fuel input rate is to be determined because the applicable standards
for certain classes of CWH equipment are based in part on the fuel
input rate. These proposed additions would clarify for manufacturers
what energy conservation standard applies to a given basic model.
DOE also proposes to include equations for determination of fuel
input rate in its test procedures for gas-fired and oil-fired CWH
equipment. DOE proposes to include Equations C2 and C3 from section
C7.2.3 of AHRI 1500-2015 in its test procedures for calculation of fuel
input rate for gas-fired and oil-fired CWH equipment, respectively. DOE
also proposes that the fuel input rate be determined by measuring fuel
consumption at 3 consecutive 10-minute intervals during the 30-minute
thermal efficiency test. The overall fuel input rate for the thermal
efficiency test will be calculated using the fuel consumption over the
entire 30-minute test. DOE proposes that during the thermal efficiency
test, the measured fuel input rate must not vary by more than 2 percent between 10-minute interval readings.
Section 5.2.2 of AHRI 1500-2015 specifies rounding gross output (as
defined in section 3.20 of AHRI 1500-2015) to the nearest 1,000 Btu/h.
However, DOE regulations are based on input rate, not gross output.
Therefore, DOE proposes adding a requirement to the DOE test procedure
that values of
[[Page 28623]]
fuel input rate for each unit tested be rounded to the nearest 1,000
Btu/h.
Additionally, DOE proposes that, for its enforcement testing, the
overall fuel input rate for the thermal efficiency test would be
measured pursuant to 10 CFR 431.106 and compared against the fuel input
rate certified by the manufacturer. If the measured fuel input rate is
within 2 percent of the certified value, then DOE will use
the certified value when determining which equipment class to regulate
a model. If the measured fuel input rate is not within 2
percent of the certified value, then DOE will attempt the following
steps to bring the fuel input rate to within 2 percent of
the certified value. First, DOE will attempt to adjust the gas pressure
in order to increase or decrease the fuel input rate within the gas
pressure range allowed by the test procedure. If the fuel input rate is
still not within 2 percent of the certified value, DOE will
then attempt to modify the gas inlet orifice (e.g. drill) accordingly.
Finally, if these measures do not bring the fuel input rate to within
2 percent of the certified value, DOE will use the measured
fuel input rate when determining the equipment class. DOE proposes a
fuel input rate tolerance of 2 percent based on the steady-
state criteria included in sections C4.1.1.1.4 and C4.1.2.1.5 of AHRI
1500-2015, and has tentatively concluded that such a requirement would
not impose additional testing burden or affect ratings. DOE proposes
this verification process to provide manufacturers with additional
information about how DOE will evaluate compliance.
Issue 21: DOE seeks comment regarding its proposed definition and
methodology for measuring and verifying fuel input rate for gas-fired
and oil-fired CWH equipment.
L. Default Values for Certain Test Parameters for Commercial Water
Heating Equipment
DOE incorporates by reference Exhibits G.1 and G.2 of ANSI
Z21.10.3-2011 (which correspond to Annexes E.1 and E.2 of ANSI
Z21.10.3-2015) in its current test procedure for thermal efficiency and
standby loss for CWH equipment. Some of the equipment settings for
performing the test procedures as per Annex E.1 of ANSI Z21.10.3-2015
(e.g., water supply pressure, venting requirements) are required to be
specified by manufacturers. DOE proposes to include default values for
these parameters in its test procedures, to be used if values are not
specified in manufacturer literature shipped with the unit \21\ or
supplemental test information. Specifically, if these values are not
included in manufacturer literature shipped with the unit, then DOE
will use the values included in the supplemental testing instructions
if one is submitted with the certification report. If the values are
neither included in manufacturer literature shipped with the unit or in
the supplemental test instructions, then DOE will use the default
values proposed in this NOPR. These test procedures and default values
would apply to commercial water heating equipment other than
residential-duty commercial water heaters.
---------------------------------------------------------------------------
\21\ Manufacturer literature includes any information on
settings, installation, and operation that is shipped with the
equipment. This information can be in the form of installation and
operation manuals, settings provided on a name plate, or product-
specific literature.
---------------------------------------------------------------------------
For all commercial water heating equipment, DOE proposes a default
value for maximum water supply pressure of 150 pounds per square inch
(psi). For gas-fired commercial water heating equipment powered with
natural gas, DOE proposes a default range of allowable gas supply
pressure of 4.5 inches of water column (in. w.c.) to 10.5 in. w.c. For
gas-fired commercial water heating equipment powered with propane, DOE
proposes a default range of 11 in. w.c. to 13 in. w.c.
DOE also includes several requirements specific to oil-fired
equipment in its current test procedure for commercial water heating
equipment as set forth in 10 CFR 431.106. These requirements include:
(1) Venting Requirements--Connect a vertical length of flue pipe to
the flue gas outlet of sufficient height so as to meet the minimum
draft specified by the manufacturer; and (2) Oil Supply--Adjust the
burner rate so that: (a) The hourly Btu input rate lies within 2 percent of the manufacturer's specified input rate, (b) the
CO2 reading shows the value specified by the manufacturer,
(c) smoke in the flue does not exceed No. 1 smoke as measured by the
procedure in ASTM-D-2156-80, and (d) fuel pump pressure lies within
10 percent of manufacturer's specifications.
These requirements depend on manufacturer specifications, including
the minimum draft, input rate, CO2 reading, and fuel pump
pressure. Manufacturers are already required to certify the input rate
of all covered oil-fired equipment in certification reports submitted
to DOE for each basic model. However, not all manufacturers describe
venting guidelines for their units using the same format and
parameters, and DOE does not wish to establish default values that
contradict manufacturer specifications. Therefore, DOE proposes to
include a default value for fuel pump pressure and a default range for
CO2 reading in its test procedures, which would only be used
if the parameters are not specified in the manufacturer's literature
shipped with the unit or in the supplemental test instructions. DOE
proposes default values of an allowable range of 9-12 percent for
CO2 reading, and 100 psig fuel pump pressure. DOE determined
these values from examination of values for units currently on the
market.
Issue 22: DOE requests comment on its proposed default values for
maximum water supply pressure for all equipment, allowable gas supply
pressure range for equipment powered with natural gas and propane, and
the CO2 reading and fuel pump pressure for oil-fired
equipment.
M. Certification Requirements
DOE proposes several changes to its certification requirements for
commercial water heating equipment \22\ at 10 CFR part 429. DOE
proposes to add two requirements to 10 CFR 429.44 for certification of
instantaneous water heaters and hot water supply boilers. First, DOE
proposes to add that manufacturers must certify whether instantaneous
water heaters or hot water supply boilers contain submerged heat
exchangers or heating elements, in order to allow for proper
classification of units under DOE's proposed definition for ``storage-
type instantaneous water heater.'' DOE's classification for storage-
type instantaneous water heaters is discussed in more detail in section
III.F. Second, DOE proposes to add that manufacturers must certify
whether instantaneous water heaters or hot water supply boilers require
flow of water through the water heater to initiate burner ignition.
---------------------------------------------------------------------------
\22\ DOE is also making an editorial change to the certification
report provisions in 10 CFR 429.44(c) for commercial water heating
equipment by replacing of the term ``water heater'' and
abbreviations of water heater (i.e., WH) with the term ``water
heating.''
---------------------------------------------------------------------------
Issue 23: DOE requests comment on its proposed additional
certification requirements for instantaneous water heaters and hot
water supply boilers, and seeks feedback on any other information that
should be included for any classes of CWH equipment.
[[Page 28624]]
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 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
regulatory 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 (OMB).
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq., as amended by
the Small Business Regulatory Enforcement Fairness Act of 1996)
requires preparation of an initial regulatory flexibility analysis
(IRFA) for any rule that by law must be proposed for public comment and
a final regulatory flexibility analysis (FRFA) for any such rule that
an agency adopts as a final rule, unless the agency certifies that the
rule, if promulgated, will not have a significant economic impact on a
substantial number of small entities. A regulatory flexibility analysis
examines the impact of the rule on small entities and considers
alternative ways of reducing negative effects. Also, 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 at: http://energy.gov/gc/office-general-counsel.
This proposed rule would prescribe test procedure amendments that
would be used to determine compliance with energy conservation
standards for CWH equipment (except for CHPWHs). The proposed
amendments would: (1) Update the referenced industry test standards by
incorporating by reference ASTM D2156-09, ASTM C177-13, ASTM C518-10,
and Annex E.1 of ANSI Z21.10.3-2015; (2) modify the thermal efficiency
and standby loss tests for CWH equipment to improve repeatability; (3)
include an updated test method for determining the efficiency of
unfired hot water storage tanks; (4) change the method for setting the
thermostat in the thermal efficiency test for gas-fired and oil-fired
storage water heaters and storage-type instantaneous water heaters from
measurement of mean tank temperature to measurement of outlet water
temperature; (5) clarify test conditions required in the thermal
efficiency test method with regard to stored energy loss and steady-
state operation; (6) define ``storage-type instantaneous water heater''
and modify several definitions for consumer water heaters and
commercial water heating equipment included at 10 CFR 430.2 and 10 CFR
431.102, respectively; (7) include a new test method for measurement of
standby loss for flow-activated instantaneous water heaters; (8)
specify temperature-sensing locations, water valve locations and
clarifications for using a recirculating loop for thermal efficiency
and standby loss testing of instantaneous water heaters and hot water
supply boilers; (9) replace the measurement of mean tank temperature
with outlet water temperature for thermostatically-activated
instantaneous water heaters (other than storage-type instantaneous
water heaters); (10) include a new test method for rating commercial
heat pump water heaters; (11) establish a procedure for determining the
fuel input rate of gas-fired and oil-fired CWH equipment and specify
DOE's measures to verify fuel input rate; (12) add default values for
certain testing parameters for commercial water heating equipment; and
(13) modify DOE's certification requirements for commercial water
heating equipment. DOE reviewed all of these proposed amendments to the
existing test procedure under the provisions of the Regulatory
Flexibility Act and the policies and procedures published on February
19, 2003. 68 FR 7990. Accordingly, DOE has prepared the following IRFA
for the equipment that is the subject of this rulemaking.
1. Description and Estimated Number of Small Entities to Which the
Proposed Rule Would Apply
For manufacturers of covered CWH equipment, the Small Business
Administration (SBA) has set a size threshold, which defines those
entities classified as ``small businesses'' for the purposes of the
statute. DOE used the SBA's small business size standards to determine
whether any small entities would be subject to the requirements of the
rule. 65 FR 30836, 30848 (May 15, 2000), as amended at 77 FR 49991,
50000, 50011 (August 20, 2012) and codified at 13 CFR part 121. The
size standards are listed by North American Industry Classification
System (NAICS) code and industry description and are available at:
http://www.sba.gov/sites/default/files/Size_Standards_Table.pdf.
Manufacturing of CWH equipment is classified under NAICS 333318,
``Other Commercial and Service Industry Machinery Manufacturing.'' \23\
The SBA sets a size threshold of 1,000 employees or fewer for a
manufacturer that falls under this category to qualify as a small
business.
---------------------------------------------------------------------------
\23\ On October 1, 2012, the NAICS code for ``Other Commercial
and Service Industry Machinery Manufacturing,'' which includes
manufacturing of commercial water heating equipment, changed from
333319 to 333318.
---------------------------------------------------------------------------
To estimate the number of companies that could be small business
manufacturers of equipment covered by this rulemaking, DOE conducted
market research and created a database of CWH equipment manufacturers
that identified the manufacturers which qualify as small businesses
among that list. DOE's research involved industry trade association
membership directories (including AHRI \24\), public databases (e.g.,
the California Energy Commission Appliance Efficiency Database \25\),
individual company Web sites, and market research tools (e.g., Hoovers
reports \26\) to create a list of companies that manufacture or sell
equipment covered by this rulemaking. DOE's research resulted in a list
of all domestic small business manufacturers of CWH equipment covered
by this rulemaking. DOE also contacted companies, as necessary, to
determine if they both meet the SBA's definition of a ``small
business'' manufacturer and have their manufacturing facilities located
within the United States. DOE screened out companies that did not offer
products covered by this rulemaking, did not meet the definition of a
``small business,'' or a foreign-owned and operated. Based upon this
analysis and comprehensive search, DOE identified 28 manufacturers of
CWH equipment affected by changes proposed in this NOPR. Of these 28,
DOE identified 16 as domestic small businesses. Fifteen of the 16
domestic small businesses are original equipment manufacturers (OEMs)
of CWH equipment covered by this rulemaking, while one rebrands
equipment manufactured by other OEMs. These fifteen small businesses
represent approximately 54 percent of domestic companies that
manufacture CWH equipment affected by changes proposed in this NOPR.
---------------------------------------------------------------------------
\24\ The AHRI Directory is available at: www.ahridirectory.org/ahriDirectory/pages/home.aspx.
\25\ The CEC database is available at: http://www.energy.ca.gov/appliances/.
\26\ Hoovers Inc., Company Profiles, Various Companies
(Available at: www.hoovers.com/).
---------------------------------------------------------------------------
[[Page 28625]]
2. Description and Estimate of Compliance Requirements
In the following sections, DOE discusses the potential burdens that
could be faced by manufacturers of CWH equipment, particularly small
businesses, as a result of each of the test procedure amendments
proposed in this NOPR.
Updated Industry Test Methods
The proposal to update the currently-referenced industry test
method edition from ANSI Z21.10.3-2011 (Exhibits G.1 and G.2) to ANSI
Z21.10.3-2015 (Annex E.1) would not impact the requirements,
conditions, or duration of DOE's test procedures. DOE only identified
one substantive difference between the efficiency test methods in each
version--the standby loss equation. Because DOE tentatively concluded
that the equation in the currently referenced ANSI Z21.10.3-2011 is
correct and proposes to retain that equation in its test procedures,
this updated reference to the industry test method should not affect
conduct of or ratings from DOE's test procedure.
DOE's current test procedure, specified at 10 CFR 431.106, also
requires that flue gases from oil-fired CWH equipment not contain smoke
that exceeds No. 1 smoke, as determined by ASTM Standard D2156-80. In
this NOPR, DOE proposed to update this reference and incorporate by
reference the most recent version of this test method, ASTM D2156-09.
DOE did not identify any significant differences between the two
versions of this test method; therefore, DOE has tentatively concluded
that this updated reference should not affect results from its test
procedure. Additionally, DOE proposes several clarifications to the
procedure for determining smoke spot number. First, DOE proposes to
clarify that the smoke spot number is to be determined once steady-
state operation is achieved but before beginning measurements for the
thermal efficiency test. Second, DOE proposes to require that the smoke
measuring device be connected to an open-ended tube that projects into
the flue \1/4\ to \1/2\ of the pipe diameter. This requirement for the
smoke measuring device is adopted from those specified for commercial
space heating boilers in AHRI 1500-2015. DOE also proposes to clarify
that the smoke spot test is required before conduct of the thermal
efficiency test or standby loss test (as applicable) of oil-fired CWH
equipment. However, DOE proposes not to require the smoke spot test be
conducted prior to beginning an efficiency test (i.e., thermal
efficiency or standby loss) if no settings on the water heater have
been changed and the water heater has not been turned off since the end
of a previously run efficiency test. DOE also proposes that the
CO2 reading be measured at the same times that are required
for determining the smoke spot number.
DOE proposes clarification of the test procedure for determining
smoke spot number because the current procedure as specified in 10 CFR
431.106 does not specify the timing or location of measuring the smoke
spot number. DOE considers conduct of the smoke spot test and
measurement of CO2 reading before the thermal efficiency
test begins to be a less burdensome method than measuring during the
test, and, therefore, does not consider this clarification likely to
increase testing burden to manufacturers. Additionally, DOE considers
its clarification regarding when the smoke spot test and measurement of
CO2 reading are not needed (i.e., when the standby loss test
is conducted after the thermal efficiency test) to reduce burden
compared to a requirement to measure before the standby loss test or
compared to the current test procedure, which simply states that the
flue cannot exceed No. 1 smoke. Finally, DOE considers its proposed
specification of the location within the flue for determination of
smoke spot number unlikely to increase burden to manufacturers, given
that this requirement was adopted from an industry-accepted test method
for similar commercial HVAC equipment.
DOE's current definition for ``R-value'' at 10 CFR 431.102
references two industry test methods, ASTM C177-97 and ASTM C518-91. In
this NOPR, DOE proposes to incorporate by reference the most recent
versions of these test methods: ASTM C177-13 and ASTM C518-10. DOE did
not identify any significant differences in the procedures for
measuring R-value between the two versions of ASTM C177 or between the
two versions of ASTM C518. Therefore, this updated reference should not
affect results for calculation of R-value per DOE's definition at 10
CFR 431.102.
Test Procedure Repeatability and Ambient Conditions
The proposed modifications to the thermal efficiency and standby
loss test methods include: (1) Stipulating a maximum air draft
requirement of 50 ft/min as measured prior to beginning the thermal
efficiency or standby loss tests; (2) tightening the ambient room
temperature tolerance from 10.0[emsp14][deg]F to 5.0[emsp14][deg]F and the allowed variance from mean ambient
temperature from 7.0[emsp14][deg]F to 2.0[emsp14][deg]F; (3) requiring measurement of test air
temperature--the temperature of entering combustion air--and requiring
the test air temperature not vary by more than 5[emsp14][deg]F from the ambient room temperature at any
measurement interval during the thermal efficiency and standby loss
tests for gas-fired and oil-fired CWH equipment; (4) establishing a
requirement for ambient relative humidity of 60 percent 5
percent during the thermal efficiency and standby loss tests for gas-
fired and oil-fired CWH equipment; (5) requiring a soak-in period prior
to testing in which the water heater must sit without any draws taking
place for at least 12 hours from the end of a recovery from a cold
start; (6) specifying the locations of inlet and outlet temperature
measurements for storage water heaters, storage-type instantaneous
water heaters, and UFHWSTs; and (7) decreasing the time interval for
data collection from fifteen minutes to 30 seconds in the thermal
efficiency and standby loss tests.
For the first modification, depending on the conditions in the
manufacturer's testing area, the manufacturer may need to protect the
testing area from drafts greater than 50 ft/min. This draft protection
could be accomplished by using wind barriers such as moveable walls,
minimizing the opening and closing of doors near the test stand, or
sealing windows. To measure draft velocity, manufacturers may have to
purchase instrumentation that DOE estimates could cost up to $250.
However, any manufacturer of residential water heaters should already
have this instrumentation and be able to comply with this stipulation,
because it is similar to the requirement established for testing
residential water heaters in the July 2014 final rule. 79 FR 40542,
40569 (July 11, 2014).
For the second, third, and fourth modifications that propose
changes to specified ambient conditions, manufacturers may not need to
make any changes if the ambient temperature and relative humidity in
their testing area already meet the proposed tolerances. DOE is aware
that the proposed constraints may in some cases require laboratories to
move testing from an uncontrolled environment (i.e., outdoors or
facilities open to the outdoors) to a controlled environment. However,
DOE understands this to be a small number of cases, and that testing is
routinely performed in a laboratory setting with typical heating,
ventilating, and air-conditioning systems and controls. DOE notes that
the limits are intended to prevent the test from being conducted in
extreme ambient conditions, and that the ambient
[[Page 28626]]
temperature requirements are typical for building heating, ventilating,
and air-conditioning systems in normal operating condition. However, if
the ambient temperature or relative humidity in the testing area do not
already meet these tolerances, the manufacturer may need to improve
climate regulation of the test environment, possibly by improving the
controls of their thermostats, or preventing hot or cold drafts from
entering the testing environment. DOE estimates that improving the
controls of the thermostat and preventing hot or cold drafts from
entering the testing environment could involve four to eight hours of
labor by a general technician. At a rate of $40 per hour for a
laboratory technician, DOE estimates the cost for this amount of labor
to be between $160 and $320, which DOE believes is modest in comparison
to the overall cost of product development and certification.\27\
---------------------------------------------------------------------------
\27\ Based on mean hourly wage from Bureau of Labor Statistics
for Mechanical Engineering Technician, occupational code 17-3027:
http://www.bls.gov/oes/current/oes173027.htm. Mean hourly wage is
multiplied by 1.5 to estimate associated benefits and overhead.
---------------------------------------------------------------------------
For the third modification, manufacturers need to measure the test
air temperature, which is measured within two feet of the combustion
air inlet. While this requirement was adopted from an industry test
method for commercial packaged boilers, AHRI 1500-2015, it is not
currently required for testing of CWH equipment. Therefore,
manufacturers would need to install temperature measuring devices in
close proximity to the air intake. However, DOE believes that a
requirement for this temperature measurement would not present any
significant testing burden to manufacturers, because it would simply
involve one more temperature measurement than is already being
conducted, and the temperature readings could be recorded using the
same data acquisition software that is used for measuring the ambient
room temperature.
The fifth modification specifies a 12-hour pre-conditioning period
prior to conducting the standby loss test for storage water heaters and
storage-type instantaneous water heaters. While this would add to the
time required to conduct the test, it would not require extra personnel
and would not necessitate the development of additional test platforms.
DOE understands that a preconditioning period is already implemented by
manufacturers as a best practice to allow the water heater to achieve
operational temperature, so the added burden from the 12-hour soak-in
would be minimal. In addition, these tests can be conducted in the same
facilities used for the current energy testing of these products, so
there would be no additional facility costs required by this proposal.
The sixth modification specifies the location for measurement of
inlet and outlet temperature for storage water heaters, storage-type
instantaneous water heaters, and UFHWSTs. DOE expects these lengths to
align with the piping set-ups currently used in most testing of CWH
equipment. If slight modifications would be needed to the set-ups
currently used, DOE believes that these modifications would be simple
and merely involve adding or removing several inches of piping.
Additionally, DOE proposes set-ups for tanks water heaters and storage
tanks with connections on the top, side, or bottom--thereby minimizing
the likelihood that a significant change to the set-up currently used
by manufacturers would be needed. Therefore, DOE has tentatively
concluded that this aspect of its proposal would not present a
significant burden to manufacturers, including small businesses.
Finally, DOE proposes reducing the time interval for data
collection during the thermal efficiency test from 1 minute to 30
seconds and during the standby loss test from 15 minutes to 30 seconds.
Because manufacturers are already required to measure at one-minute
intervals for the current thermal efficiency test, DOE reasons that
manufacturers already use a computer-connected data acquisition system.
Changing the time intervals for recording measurements on a data
acquisition system is a quick process that requires the operator to
simply change the parameters on the computer using the data acquisition
system software. Therefore, the manufacturers would not incur any
additional testing costs due to the proposed changes in the data
recording time intervals.
Unfired Hot Water Storage Tanks
DOE also proposes to adopt a new metric and test procedure for
testing the efficiency of unfired hot water storage tanks. In order to
comply with Federal regulations, unfired hot water storage tanks are
currently required to meet a minimum thermal insulation R-value of 12.5
[middot][deg]F[middot]ft\2\[middot]h/Btu. In this NOPR, DOE proposes to
adopt a new standby loss metric determined by a new standby loss test
method for this class. If this test procedure is adopted, certification
of standby loss for covered unfired hot water storage tanks would not
be required unless and until DOE establishes energy conservation
standards in terms of standby loss for this class. However, DOE
acknowledges that absent a standby loss standard, some manufacturers
may choose to rate the efficiency of their unfired hot water storage
tank models to help distinguish their products from competitor
offerings.
Manufacturers likely already have all necessary equipment and
instrumentation for the proposed test method for unfired hot water
storage tanks, because such equipment and instrumentation are already
needed for testing of other CWH equipment classes. Through its review
of the market, DOE found that all unfired hot water storage tank
manufacturers also produce other covered CWH equipment, such as storage
water heaters, instantaneous water heaters, or hot water supply
boilers. Therefore, DOE has tentatively concluded that manufacturers
would not incur any additional test facility costs. Small manufacturers
with a small number of UFHWST offerings could choose to conduct testing
with a third-party lab, which DOE estimates would cost no more than
$3,000 per tested UFHWST.
DOE estimates that testing of each unfired hot water storage tank
would take less than 2 days, including set-up and testing of storage
volume and standby loss. However, the majority of this time would not
require attendance by any employees. DOE estimates that setting up and
removing the unfired hot water storage tanks from the test stand might
require 2-3 hours of time from a laboratory technician. At a rate of
$40 per hour for a laboratory technician, DOE estimates the cost for
this amount of labor to be no more than $80-$120. Additionally, DOE
estimates it would take approximately 1 hour of a lab technician's time
to complete the test procedure per model tested, which would result in
a cost of $40. Therefore, the total labor cost of testing an unfired
hot water storage tank would be $120-$160 per model.
Issue 24: DOE requests comment on its cost estimates for
manufacturers to test their unfired hot water storage tanks according
to DOE's proposed test method.
Thermostat Settings
DOE proposes to change the measurement of temperature in the
thermal efficiency test by measuring the outlet water temperature
rather than the mean tank temperature for gas-fired and oil-fired
storage water heaters and storage-type instantaneous water
[[Page 28627]]
heaters. This proposal was suggested by manufacturers so that their
models can more easily meet the specified conditions in the test
procedure without having to sacrifice thermal efficiency gains when
designing equipment. Because the outlet water temperature is already
measured in the current test method, this proposal would simplify DOE's
test procedure, and would not create any additional test burden for
manufacturers, including small businesses.
Clarifications to the Thermal Efficiency and Standby Loss Test
Procedures
DOE proposes to add clarifying statements to its thermal efficiency
and standby loss test procedures. Specifically, DOE proposes to clarify
that that during the thermal efficiency test, the burner must
continuously fire at the full firing rate for the entire duration of
the test and that the outlet water temperature must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature. DOE also proposes to clarify that during the thermal
efficiency and standby loss tests, no settings on the water heating
equipment can be changed until measurements for the test have finished.
As discussed in section III.E, several manufacturers indicated that
there was not a problem with the current test procedure, as there is a
general understanding that the burner must fire at its full input rate
throughout the course of the test. Additionally, DOE expects that the
majority of manufacturers already perform the thermal efficiency and
standby loss tests in a manner as clarified in DOE's proposal.
Therefore, DOE has tentatively concluded that its proposed clarifying
statements would only serve to remove any potential confusion regarding
its test procedures, and would not add any burden to manufacturers,
including small businesses.
Storage-Type Instantaneous Water Heaters
DOE proposes a new definition for ``storage-type instantaneous
water heater,'' which are instantaneous water heaters with integral
storage tanks and a submerged heat exchanger(s) or heating element(s).
DOE believes this kind of water heater should be tested similar to
storage water heaters. However, DOE does not currently prescribe
separate test procedures for storage water heaters and instantaneous
water heaters. Only in the test procedures proposed in this NOPR does
DOE prescribe separate standby loss test methods for storage water
heaters and instantaneous water heaters. Additionally, DOE's research
suggests that manufacturers already categorize units falling under
DOE's proposed definition for ``storage-type instantaneous water
heater'' with storage water heaters. Therefore, DOE has tentatively
concluded that applying the test procedure prescribed for storage water
heaters to storage-type instantaneous water heaters would not present a
burden for manufacturers, including small businesses.
Flow-Activated Instantaneous Water Heaters
Currently, all instantaneous water heaters and hot water supply
boilers having a capacity of 10 gallons or more are required to undergo
the same standby loss test that is prescribed in Exhibit G.2 of ANSI
Z21.10.3-2011. However, in this NOPR, DOE is proposing a new and
separate standby loss test procedure for flow-activated instantaneous
water heaters.
In the proposed standby loss test procedure, the flow-activated
instantaneous water heater being tested would not cycle on at any point
in the course of the test. Therefore, the amount of fuel consumption is
not needed for standby loss calculations. This modification will
simplify the test and reduce the amount of data processing required for
calculating standby loss metric. As a result, this modification would
be beneficial to all manufacturers, including small businesses.
The second difference pertains to the duration of the test. In the
current test procedure, the equipment is tested until the first cut-out
that occurs after 24 hours or 48 hours, whichever comes first. In the
proposed standby loss test procedure for flow-activated instantaneous
water heaters, the test ends when the outlet water temperature drops by
35[emsp14][deg]F or after 24 hours, whichever comes first. DOE has
tentatively concluded that it is very likely that a 35[emsp14][deg]F
drop in outlet water temperature will occur before 24 hours. Therefore,
this proposed modification would likely be beneficial to all
manufacturers, including small businesses, as it would reduce the time
required to conduct the standby loss test. In addition, DOE notes that
the maximum test length of 24 hours in the proposed test method is the
same as the current minimum test length in the existing test procedure,
so the proposed test would always result in a test length either
shorter or equal to that of the current test.
The third difference is with regards to the measurement recording
intervals. In the current test procedure, the time interval between two
successive readings is 1 minute for the thermal efficiency test and 15
minutes for a standby loss test. In the proposed standby loss test
method for flow-activated instantaneous water heaters, DOE has proposed
to shorten the time interval to 30 seconds. As with other types of CWH
equipment, because manufacturers are already required to measure at
one-minute intervals for the thermal efficiency test, DOE believes that
manufacturers already use a computer-connected data acquisition system.
Changing the time intervals for recording measurements on a data
acquisition system is a quick process that requires the operator to
simply change the parameters on the computer using the data acquisition
system software. Therefore, DOE believes that manufacturers would not
incur any additional testing costs due to the proposed changes in the
data recording time intervals.
In summary, DOE has tentatively concluded that the proposed standby
loss test procedure for flow-activated water heaters would not impose
any significant additional burden on manufacturers, including small
businesses.
Changes to the Test Set-Up for Instantaneous Water Heaters and Hot
Water Supply Boilers
For the thermal efficiency and standby loss tests of instantaneous
water heaters and hot water supply boilers, DOE proposes to move the
outlet water temperature-sensing location closer to the CWH equipment
being tested, with several requirements for the placement of the
temperature-sensing probe in the outlet water line. DOE also proposes
to require the supply water valve be within a distance of 5 inches and
an outlet water valve be within a distance of 10 inches from the water
heater jacket. These modifications in the test set-up would require:
(1) Moving the tee pipe fitting that is used to hold the outlet water
temperature sensing instrument to a location immediately outside the
CWH equipment; and (2) moving the supply water valve and outlet water
valve that are already installed further away from the water heater to
the a location closer to the CWH equipment. In case a new tee is
required, DOE estimates that such a fitting would cost approximately
$50. DOE reasons that the benefits of better representation of the
outlet water temperature and close proximity of the water valves that
need to be shut off to retain the hot water in the water heater during
the standby loss test outweighs the small potential cost of an
additional pipe fitting. In addition to these changes, DOE also
proposes to clarify
[[Page 28628]]
the conditions for using a recirculating loop. The use of a
recirculating loop is allowed in the current test procedure, and, thus,
this modification would not cause an increase in testing cost.
Therefore, DOE has tentatively concluded that the adjustments described
in this paragraph would not impose a significant burden on
manufacturers, including small businesses.
Modified Standby Loss Test Procedure for Instantaneous Water Heaters
and Hot Water Supply Boilers
DOE's current standby loss test procedure for CWH equipment at 10
CFR 431.106, which incorporates by reference Exhibit G.2 of ANSI
Z21.10.3-2011, requires the measurement of the mean tank temperature to
calculate standby loss. In this NOPR, DOE proposes to replace the
measurement of mean tank temperature with the outlet water temperature
for conducting the standby loss test for instantaneous water heaters
and hot water supply boilers that do not meet DOE's proposed definition
of ``storage-type instantaneous water heater.'' This proposed
modification to the current test procedure would only change the terms
that are used in calculating standby loss. The recording of the outlet
water temperature is already required in the thermal efficiency test
procedure for all CWH equipment. Therefore, the only change that the
manufacturers would be required to make would be to record the outlet
water temperature during the standby loss test. Accordingly, DOE has
tentatively concluded that these proposed changes would not be unduly
burdensome to manufacturers, including small businesses.
Commercial Heat Pump Water Heaters
DOE currently does not prescribe a test procedure for commercial
heat pump water heaters. In this NOPR, DOE proposes to adopt a new test
procedure for measurement of the COPh of CHPWHs. If this
test procedure is adopted, certification of COPh for CHPWHs
would not be required unless and until DOE establishes energy
conservation standards for this class in terms of COPh.
However, DOE acknowledges that in the absence of a Federal
COPh standard, some manufacturers may choose to rate the
efficiency of their commercial heat pump water heaters to help
distinguish their equipment from competitor offerings.
DOE believes that manufacturers of CHPWHs already have the
equipment, instrumentation, and facilities (including psychrometric
chambers) for testing their units according to the proposed test
method, because these would be needed for product development and
measurement of COPh values absent a DOE test method.
However, DOE acknowledges that some manufacturers may need to purchase
equipment, instrumentation, or test stands for measurement of
COPh according to the proposed test method. For testing air-
source CHPWH units, DOE estimates that the cost to build a test stand
and a surrounding psychrometric chamber for the testing of CHPWHs would
cost no more than $300,000. While the duration of the proposed test for
air-source CHWPHs is 30 minutes, DOE estimates the total time,
including the time needed for set-up and stabilizing the outlet water
temperatures prior to the test, may reach five hours. At a rate of $40
per hour for a laboratory technician, DOE estimates the cost for this
labor would be $200 per model tested.
Given the small market size of air-source CHPWHs, DOE believes that
most manufacturers without test facilities capable of testing air-
source CHPWHs according to DOE's proposed test procedure would choose
to conduct testing at a third-party lab. DOE estimates that the average
air-source CHPWH manufacturer sells six models, and that the cost of
testing an air-source CHPWH would not exceed $10,000. Therefore, the
average testing burden for manufacturers of air-source CHPWHs without
testing facilities should not exceed $60,000.
For indoor water-source and ground water-source CHPWHs, water
solution conditioning and recirculation equipment similar to a chiller
would be required for testing, in addition to equipment needed for
testing air-source CHPWHs (e.g., standard piping, instrumentation, a
data acquisition system, and test stand). DOE expects most
manufacturers already have such equipment in order to test and provide
ratings for their current product offerings. However, DOE acknowledges
that there may be some manufacturers that do not currently have
equipment sufficient for conducting DOE's proposed test procedure. DOE
estimates the total cost of a chiller to be about $20,000. The cost of
instrumentation, piping, and a data acquisition unit could add up to an
additional $5,000. Therefore, DOE does not expect capital investments
would exceed $25,000 per manufacturer. DOE estimates that following the
test procedure, it would take approximately 5-6 hours to set up the
unit and to conduct the test. At a lab technician labor cost of $40 per
hour, DOE estimates the total labor cost incurred to test each unit
would be between $200 and $240. Alternatively, some manufacturers,
including small businesses, may choose to test their units at third-
party laboratories instead of investing in in-house testing facilities.
DOE estimates that the cost of such testing would not exceed $3,000 per
unit. DOE estimates that manufacturers may test about 6 models annually
at third-party laboratories. Therefore, the total estimated cost burden
for any such manufacturers would not be more than $18,000.
Based on the proposed test procedure, the test set-up for ground or
indoor water-source CHPWHs would be similar to that for direct geo-
exchange CHPWHs, with the only difference being that the test set-up
for direct geo-exchange CHPWHs includes an additional solution heat
exchanger. Similar to water-source CHPWHs, DOE expects that most
manufacturers of direct geo-exchange CHPWHs already have such equipment
in order to test and provide ratings for their current product
offerings. DOE understands that the cost of this solution heat
exchanger would be the only cost to be added to the total estimated
cost for testing ground and indoor water-source CHPWHs in order to
arrive at the estimated cost of testing a direct geo-exchange CHPWH.
DOE estimates the cost of a liquid-to-liquid heat exchanger to be not
more than $30,000. Therefore, the total estimated capital investment
cost for testing a direct geo-exchange CHPWH would not exceed $55,000.
Similar to water-source CHPWH manufacturers, DOE understands that many
manufacturers of direct geo-exchange CHPWHs, including small
businesses, may choose to test their units at third-party laboratories
instead of investing in in-house testing facilities. DOE estimates the
cost of such testing would not exceed $5,000 per unit.
Default Values for Certain Test Parameters
In this NOPR, DOE proposes to add to its test procedure at 10 CFR
431.106 default values for certain test parameters for CWH equipment,
to be used if manufacturers do not report these in either the product
literature that is shipped with the unit (e.g., installation and
operations manual), or their supplemental instructions. DOE proposes
the following default values: (1) A maximum allowable water pressure
for all CWH equipment; (2) an allowable gas pressure range for gas-
fired CWH equipment; and (3) fuel pump pressure and a range for
CO2 reading for oil-fired CWH equipment.
[[Page 28629]]
DOE does not expect the proposed default values to present a
significant burden to manufacturers because these are basic parameters
needed for proper use of CWH equipment and are, therefore, typically
specified in manufacturer literature shipped with the unit.
3. Duplication, Overlap, and Conflict With Other Rules and Regulations
DOE is not aware of any rules or regulations that duplicate,
overlap, or conflict with the rule being proposed in this document.
4. Significant Alternatives to the Proposed Rule
DOE considered alternative test methods and modifications to the
test procedures for CWH equipment, and tentatively determined that
there are no better alternatives than the modifications and procedures
proposed in this NOPR. DOE examined relevant industry test standards,
and incorporated these standards in the proposed test procedures
whenever appropriate to reduce test burden to manufacturers.
Specifically, this NOPR updates its test procedures for CWH equipment
to incorporate by reference the following updated standards: ASTM
D2156-09, ASTM C177-13, ASTM C518-10, and Annex E.1 of ANSI Z21.10.3-
2015. Additionally, DOE proposes three new test procedures in this
NOPR: A standby loss test procedure for UFHWSTs, a standby loss test
procedure for flow-activated instantaneous water heaters, and a test
procedure for measurement of COPh of CHPWHs. For the
COPh test for CHPWHs and the standby loss test for UFHWSTs,
DOE proposes to incorporate by reference industry-accepted test methods
(ASHRAE 118.1-2012 and sections 4, 5, 6.0, and 6.1 of GAMA Testing
Standard IWH-TS-1, respectively). For the standby loss test procedure
for flow-activated instantaneous water heaters, DOE proposes a test
procedure similar to that recommended by AHRI in supplemental public
comments to the February 2014 RFI, with modifications.
C. Review Under the Paperwork Reduction Act of 1995
Manufacturers of CWH equipment 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 CWH equipment, including any amendments
adopted for those test procedures, on the date that compliance is
required. DOE has established regulations for the certification and
recordkeeping requirements for all covered consumer products and
commercial equipment, including CWH equipment. 76 FR 12422 (March 7,
2011); 80 FR 5099 (Jan. 30, 2015). The collection-of-information
requirement for 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 commercial water heating equipment. 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 procedure 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 (CX) 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, DOE has made a CX determination for this rulemaking, and
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 10,
1999), imposes certain requirements on Federal 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 tentatively 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 equipment that is 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)) Therefore, Executive Order 13132 requires no further
action.
F. Review Under Executive Order 12988
With respect to 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. Regarding the review required by section 3(a),
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
[[Page 28630]]
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
tentatively 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 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 them. On March 18, 1997, DOE published
a statement of policy on its process for intergovernmental consultation
under UMRA. 62 FR 12820. (This policy is also available at
www.energy.gov/gc/office-general-counsel under ``Guidance & Opinions''
(Rulemaking)) DOE examined the proposed rule according to UMRA and its
statement of policy and has tentatively determined that the rule
contains neither an intergovernmental mandate, nor a mandate that may
result in the expenditure by State, local, and Tribal governments, in
the aggregate, or by the private sector, of $100 million or more in any
year. Accordingly, no further assessment or analysis is required under
UMRA.
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
Pursuant to Executive Order 12630, ``Governmental Actions and
Interference with Constitutionally Protected Property Rights,'' 53 FR
8859 (March 18, 1988), DOE has determined that this proposed rule would
not result in any takings that might require compensation under the
Fifth Amendment to the U.S. Constitution.
J. Review Under the 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 Federal agencies to review
most disseminations of information to the public under information
quality 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 the
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 OIRA
at 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 promulgates 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.
DOE has tentatively concluded that the regulatory action in this
document, which proposes amendments to the test procedure for measuring
the energy efficiency of commercial water heating equipment, is not a
significant energy action because it 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. Accordingly, DOE has not prepared a
Statement of Energy Effects for this proposed rule.
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 et seq.), DOE must comply with all laws
applicable to the former Federal Energy Administration, including
section 32 of the Federal Energy Administration Act of 1974 (Pub. L.
93-275), as amended by the Federal Energy Administration Authorization
Act of 1977 (Pub. L. 95-70). (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.
This proposed rule incorporates testing methods contained in the
following commercial standards: (1) GAMA IWH-TS-1, ``Method to
Determine Performance of Indirect-Fired Water Heaters,'' March 2003
edition, sections 4, 5, 6.0, and 6.1; (2) ANSI Z21.10.3-2015/CSA 4.3-
2015, ``Gas-fired Water Heaters, Volume III, Storage Water Heaters with
Input Ratings Above 75,000 Btu Per Hour, Circulating and
Instantaneous,'' annex E.1; (3) ANSI/ASHRAE Standard 118.1-2012,
``Method of Testing for Rating Commercial Gas, Electric, and Oil
Service Water-Heating Equipment''; (4) ASTM D2156-09, ``Standard Test
Method for Smoke Density in Flue Gases from Burning Distillate Fuels'';
(5) ASTM C177-13, ``Standard Test Method
[[Page 28631]]
for Steady-State Heat Flux Measurements and Thermal Transmission
Properties by Means of the Guarded-Hot-Plate Apparatus''; and (6) ASTM
C518-10, ``Standard Test Method for Steady-State Thermal Transmission
Properties by Means of the Heat Flow Meter Apparatus.'' While the
proposed test procedures are not exclusively based on these standards,
DOE's test procedures would adopt several provisions from these
standards 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 NOPR, DOE proposes to incorporate by reference the
following test standards:
(1) GAMA IWH-TS-1, ``Method to Determine Performance of Indirect-
Fired Water Heaters,'' March 2003 edition, sections 4, 5, 6.0, and 6.1;
(2) ANSI Z21.10.3-2015/CSA 4.3-2015, ``Gas-fired Water Heaters,
Volume III, Storage Water Heaters with Input Ratings Above 75,000 Btu
Per Hour, Circulating and Instantaneous,'' annex E.1;
(3) ANSI/ASHRAE Standard 118.1-2012, ``Method of Testing for Rating
Commercial Gas, Electric, and Oil Service Water-Heating Equipment'';
(4) ASTM D2156-09, ``Standard Test Method for Smoke Density in Flue
Gases from Burning Distillate Fuels'';
(5) ASTM C177-13, ``Standard Test Method for Steady-State Heat Flux
Measurements and Thermal Transmission Properties by Means of the
Guarded-Hot-Plate Apparatus''; and
(6) ASTM C518-10, ``Standard Test Method for Steady-State Thermal
Transmission Properties by Means of the Heat Flow Meter Apparatus.''
GAMA IWH-TS-1 (March 2003 edition) is an industry-accepted test
procedure for measuring the performance of indirect water heaters. In
this NOPR, DOE proposes to incorporate by reference sections of this
test procedure that address test set-up, instrumentation, and test
conditions. GAMA IWH-TS-1, March 2003 edition, is available on AHRI's
\28\ Web site at http://www.ahrinet.org/App_Content/ahri/files/standards%20pdfs/Indirect-Fired%20Water%20Heater%20Testing%20Standard03.pdf.
---------------------------------------------------------------------------
\28\ ARI and GAMA merged to become AHRI on January 1, 2008.
---------------------------------------------------------------------------
ANSI Z21.10.3-2015/CSA 4.3-2015 is an industry-accepted test
procedure for measuring the performance of commercial water heaters. In
this NOPR, DOE proposes to incorporate by reference sections of this
test procedure that address test set-up, instrumentation, test
conditions, and test conduct. ANSI Z21.10.3-2015/CSA 4.3-2015 is
available on ANSI's Web site at http://webstore.ansi.org/RecordDetail.aspx?sku=ANSI+Z21.10.3-2015%2fCSA4.3-2015.
ANSI/ASHRAE Standard 118.1-2012 is an industry-accepted test
procedure for measuring the performance of commercial water heaters.
ANSI/ASHRAE 118.1-2012 is available on ANSI's Web site at http://webstore.ansi.org/RecordDetail.aspx?sku=ANSI%2FASHRAE+Standard+118.1-2012.
ASTM D2156-09 is an industry-accepted test procedure for
determining the smoke spot number of flue gases. ASTM D2156-09 is
available on ASTM's Web site at http://www.astm.org/Standards/D2156.htm.
ASTM C177-13 is an industry-accepted test procedure for determining
the R-value of a sample using a guarded-hot-plate apparatus. ASTM C177-
13 is available on ASTM's Web site at http://www.astm.org/Standards/C177.htm.
ASTM C518-10 is an industry-accepted test procedure for determining
the R-value of a sample using a heat flow meter apparatus. ASTM C518-10
is available on ASTM's Web site at http://www.astm.org/Standards/C518.htm.
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 Ms. Brenda Edwards
at (202) 586-2945 or [email protected]. All participants will
undergo security processing upon building entry, and foreign nationals
visiting DOE Headquarters 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 of this fact 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 must undergo additional
screening and will be required to obtain a property pass. Visitors
should avoid bringing laptops, or allow an extra 45 minutes to check
in. Please report to the visitors 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 identification
(ID) requirements for individuals wishing to enter Federal buildings
from specific States and U.S. territories. As a result, driver's
licenses from the following States or territory will not be accepted
for building entry, and instead, 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 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, attendees may participate in 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=36. Participants are responsible for ensuring
their systems are compatible with the webinar software.
The purpose of the meeting is to receive oral and written comments,
data, and other information that would provide understanding about
potential issues associated with this rulemaking. DOE must receive
requests to speak at the meeting before 12:00 a.m. EST, June 3, 2016.
DOE must receive a signed original and an electronic copy of any
statement to be given at the public
[[Page 28632]]
meeting before 12:00 a.m. EST, June 3, 2016.
B. Procedure for Submitting Requests To Speak and Prepared General
Statements for Distribution
Any person who has an interest in the topics addressed in this
document, or who is representative of a group or class of persons that
has an interest in these issues, may request an opportunity to make an
oral presentation at the public meeting. Such persons may hand-deliver
requests to speak to the address shown in the ADDRESSES section at the
beginning of this document between 9:00 a.m. and 4:00 p.m., Monday
through Friday, except Federal holidays. Requests may also be sent by
mail or email to Ms. Brenda Edwards, U.S. Department of Energy,
Building Technologies Office, Mailstop EE-5B, 1000 Independence Avenue
SW., Washington, DC 20585-0121, or [email protected]. Persons
who wish to speak should include with their request a computer diskette
or CD-ROM in WordPerfect, Microsoft Word, PDF, or text (ASCII) file
format that briefly describes the nature of their interest in this
rulemaking and the topics they wish to discuss. Such persons should
also provide a daytime telephone number where they can be reached.
DOE requests persons scheduled to make an oral presentation to
submit an advance copy of their statements at least one week before the
public meeting. At its discretion, DOE may permit persons who cannot
supply an advance copy of their statement to participate, if those
persons have made advance alternative arrangements with the Building
Technologies Office. As necessary, requests to give an oral
presentation should ask for such alternative arrangements.
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. There shall not be discussion of proprietary
information, costs or prices, market share, or other commercial matters
regulated by U.S. anti-trust laws. After the public meeting and until
the end of the comment period, interested parties may submit further
comments on the proceedings and any aspect of the rulemaking.
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 and will be accessible on the DOE Web site. 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 before or after the public meeting, but no later than the
date provided in the DATES section at the beginning of this proposed
rule. Interested parties may submit comments, data, and other
information using any of the methods described in the ADDRESSES section
at the beginning of this notice of proposed rulemaking.
Submitting comments via www.regulations.gov. The
www.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 itself 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. Otherwise, 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 www.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
www.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 which follows.
DOE processes submissions made through www.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 www.regulations.gov
provides after you have successfully uploaded your comment.
Submitting comments via email, hand delivery/courier, or mail.
Comments and documents submitted via email, hand delivery/courier, or
mail also will be posted to www.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 in 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.
Include contact information each time you submit comments, data,
documents, and other information to DOE. If you submit via mail or hand
delivery/courier, please provide all items on a
[[Page 28633]]
CD, if feasible, in which case it is not necessary to submit printed
copies. No telefacsimiles (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, that are written in English, and that are 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. Pursuant 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/courier 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 seeks comment on its proposed incorporation by
reference of ASTM D2156-09, and on its proposed additional
specifications for how to set up the smoke spot test, and when to
conduct the smoke spot test and measure the CO2 reading.
Issue 2: DOE seeks comment on its proposed incorporation by
reference of ASTM C177-13 and C518-10 for the definition of ``R-
value.''
Issue 3: DOE requests comments and data on its proposed changes to
improve the repeatability of the thermal efficiency and standby loss
test procedures for certain commercial water heating equipment.
Specifically, DOE requests comment on its proposed requirements for
ambient relative humidity. DOE does not propose this requirement for
testing of electric water heaters, and seeks feedback on whether
including such a requirement would improve the repeatability of the
standby loss test for electric water heaters. DOE is also seeking
comments regarding any additional changes that would improve the
repeatability of the thermal efficiency and standby loss tests.
Issue 4: DOE requests comment on the changes to improve test
repeatability for its test procedures for certain CWH equipment that
were identified but not proposed in this NOPR. If comments suggest that
DOE should implement these changes, then DOE will evaluate whether it
can adopt those changes in the final rule or must engage in further
rulemaking. Particularly, DOE requests data showing what duration for
the steady-state verification period would ensure steady-state
operation is reached for gas-fired and oil-fired CWH equipment prior to
the thermal efficiency test. DOE also seeks data that suggest suitable
tolerances for water temperature and flow rate for this steady-state
verification period. Additionally, DOE seeks comment on whether
different requirements for establishing steady-state operation are
warranted for each equipment class of CWH equipment.
Issue 5: DOE requests comment on the proposed test procedure to
determine the standby loss for UFHWSTs, and on whether any other
methods, including those detailed in this NOPR, would lead to a better
test. Specifically, DOE solicits feedback on whether the proposed test
would be long enough to determine an accurate standby loss rating,
whether the use of a linear approximation of the temperature decay is
sufficient to estimate the standby loss, whether running the test by
simply letting the temperature decay (rather than providing external
heat to bring the temperature of the water back to operational
temperature) is appropriate, and whether the adoption of test
conditions (i.e., ambient room temperature, maximum air draft, water
temperature) similar to that of other classes of CWH equipment is
appropriate. DOE also seeks comment on whether any of its identified
alternatives could be modified to improve their repeatability and to
decrease test burden, thereby supporting further consideration.
Issue 6: DOE seeks comment on its proposed change to its
requirements for setting the tank thermostat in the thermal efficiency
and standby loss test procedures for gas-fired and oil-fired storage
and storage-type instantaneous water heaters from measurement of mean
tank temperature to measurement of outlet water temperature.
Issue 7: DOE seeks comment on its tentative decision to maintain a
mean tank temperature requirement for the standby loss test for
electric storage water heaters. DOE also requests comment on its
clarifying language for setting tank thermostats for electric storage
water heaters with multiple thermostats.
Issue 8: DOE requests comment on its proposed clarifying statements
regarding steady-state operation and manipulation of CWH equipment
settings during efficiency tests.
Issue 9: DOE requests comment on its proposal to remove exemptions
from the definitions for consumer water heaters codified at 10 CFR
430.2 that exclude units that heat water to temperatures greater than
180[emsp14][deg]F and units with a storage capacity greater than 120
gallons. DOE also requests comment on its proposal to remove the
definitions at 10 CFR 430.2 for ``electric heat pump water heater'' and
``gas-fired heat pump water heater.''
Issue 10: DOE requests comment on its proposed changes to its
definitions for CWH equipment: (1) Replacing the terms ``rated input''
and ``input rating'' with ``fuel input rate'' for gas-fired and oil-
fired CWH equipment to match DOE's proposed definition for ``fuel input
rate;'' (2) modifying DOE's definitions for ``instantaneous water
heater'' and ``storage water heater'' by adding the input criteria that
separate consumer water heaters and commercial water heaters and
removing several phrases that do not serve to clarify coverage of units
under the definitions;
[[Page 28634]]
and (3) removing the definition of ``packaged boiler.''
Issue 11: DOE requests comment on its proposal to modify the
definition of ``residential-duty commercial water heater'' by removing
from its scope the following classes: Electric storage water heaters,
heat pump water heaters with storage, gas-fired instantaneous water
heaters, and oil-fired instantaneous water heaters.
Issue 12: DOE seeks comment on its proposed definition of
``storage-type instantaneous water heater.''
Issue 13: DOE requests comment on its proposed definition for
``flow-activated instantaneous water heater.'' Specifically, DOE
requests feedback on whether the definition includes all units and
designs for which a separate standby loss test procedure is warranted,
and whether any units would be included that do not need a test method
separate from the current standby loss test procedure for CWH
equipment.
Issue 14: DOE requests comment on its proposal to include a test
procedure similar to that specified in section 5.27 of ANSI Z21.10.3-
2015 for measuring the storage volume of all instantaneous water
heaters and hot water supply boilers, including flow-activated
instantaneous water heaters. DOE also seeks information on alternative
methods for measuring storage volume and the impact of residual water
on measuring storage volume of instantaneous water heaters and hot
water supply boilers. Further, DOE seeks comment on ways to remove
residual water from the water heater that could allow for more accurate
and consistent measurement of the storage volume of CWH equipment.
Issue 15: DOE requests comment from interested parties on all
aspects of the proposed test procedure for flow-activated instantaneous
water heaters. Specifically, DOE requests comment on its tentative
decision to: (1) Base the test procedure on the second part of the 2016
AHRI-recommended test method that applies to flow-activated water
heaters that will not initiate burner operation over the course of the
test; (2) stop the test following a 35[emsp14][deg]F
2[emsp14][deg]F drop in the outlet water temperature or completion of
24 hours, whichever occurs earlier; and (3) use the outlet water
temperature as an approximation of the stored water temperature.
Issue 16: DOE seeks comment on its proposed change to the location
of temperature measurement for the outlet water temperature with the
associated conditions for placement of temperature-sensing instruments
in water pipes, as well as the placement of the supply and outlet water
valves. Specifically, DOE requests comment on whether such a change
would provide more accurate test results, and whether the change would
be burdensome to manufacturers. Additionally, DOE requests information
on any alternative arrangements to measure the outlet water temperature
accurately and in close proximity to the hot water outlet of the tested
CWH equipment.
Issue 17: DOE requests comment on the proposed test procedure for
instantaneous water heaters and hot water supply boilers (except those
meeting the proposed definition of ``storage-type instantaneous water
heater'' and ``flow-activated instantaneous water heater''). DOE also
requests feedback on its tentative decision to use the outlet water
temperature instead of the mean tank temperature or stored water
temperature to conduct the standby loss test. Further, DOE requests
suggestions on methods or approaches that can be used to measure the
stored water temperature accurately.
Issue 18: DOE requests comment on its proposed definition for
``commercial heat pump water heater.''
Issue 19: DOE requests comment on the proposed categories of CHPWHs
and related definitions. In particular, DOE requests comments on CHPWH
heat sources that are currently available for commercial applications.
Issue 20: DOE requests comment on all aspects of the proposed test
procedure for commercial heat pump water heaters, and in particular,
the proposal to test all units without a storage tank. DOE also invites
comment on its recommended rating conditions, particularly the supply
water temperatures for air-source commercial heat pump water heaters.
Issue 21: DOE seeks comment regarding its proposed definition and
methodology for measuring and verifying fuel input rate for gas-fired
and oil-fired CWH equipment.
Issue 22: DOE requests comment on its proposed default values for
maximum water supply pressure for all equipment, allowable gas supply
pressure range for equipment powered with natural gas and propane, and
the CO2 reading and fuel pump pressure for oil-fired
equipment.
Issue 23: DOE requests comment on its proposed additional
certification requirements for instantaneous water heaters and hot
water supply boilers, and seeks feedback on any other information that
should be included for any classes of CWH equipment.
Issue 24: DOE requests comment on its cost estimates for
manufacturers to test their unfired hot water storage tanks according
to DOE's proposed test method.
VI. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this notice of
proposed rulemaking.
List of Subjects
10 CFR Part 429
Confidential business information, Energy conservation, Household
appliances, Imports, Reporting and recordkeeping requirements.
10 CFR Part 430
Administrative practice and procedure, Confidential business
information, Energy conservation, Household appliances, Imports,
Intergovernmental relations, Small businesses.
10 CFR Part 431
Administrative practice and procedure, Confidential business
information, Incorporation by reference, Test procedures, Reporting and
recordkeeping requirements.
Issued in Washington, DC, on April 15, 2016.
Kathleen B. Hogan,
Deputy Assistant Secretary for Energy Efficiency, Energy Efficiency and
Renewable Energy.
For the reasons set forth in the preamble, DOE proposes to amend
parts 429, 430, and 431 of chapter II, subchapter D of title 10, 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 429.44 is amended by:
0
a. Revising paragraphs (b) and (c);
0
b. Redesignating paragraph (d) as (e) and revising newly redesignated
paragraph (e); and
0
c. Adding and reserving a new paragraph (d).
The additions and revisions read as follows:
Sec. 429.44 Commercial water heating equipment.
* * * * *
(b) Determination of represented values for all types of commercial
water heaters except residential-duty
[[Page 28635]]
commercial water heaters. Manufacturers must determine the represented
values, which includes the certified ratings, for each basic model of
commercial water heating equipment except residential-duty commercial
water heaters, either by testing, in conjunction with the applicable
sampling provisions, or by applying an AEDM as set forth in Sec.
429.70.
(1) Units to be tested. If the represented value for a given basic
model is determined through testing:
(i) The general requirements of Sec. 429.11 apply; and
(ii) A sample of sufficient size must be randomly selected and
tested to ensure that:
(A) Any represented value of energy consumption or other measure of
energy use of a basic model for which consumers would favor lower
values must be greater than or equal to the higher of:
(1) The mean of the sample, where:
[GRAPHIC] [TIFF OMITTED] TP09MY16.273
And, x is the sample mean; n is the number of samples; and
xi is the ith sample; or,
(2) The upper 95 percent confidence limit (UCL) of the true mean
divided by 1.05, where:
[GRAPHIC] [TIFF OMITTED] TP09MY16.274
And x is the sample mean; s is the sample standard deviation; n is the
number of samples; and t0.95 is the t statistic for a 95%
one-tailed confidence interval with n-1 degrees of freedom (from
appendix A to subpart B of this part). And,
(B) Any represented value of energy efficiency or other measure of
energy consumption of a basic model for which consumers would favor
higher values must be less than or equal to the lower of:
(1) The mean of the sample, where:
[GRAPHIC] [TIFF OMITTED] TP09MY16.275
And, x is the sample mean; n is the number of samples; and
xi is the ith sample; or,
(2) The lower 95 percent confidence limit (LCL) of the true mean
divided by 0.95, where:
[GRAPHIC] [TIFF OMITTED] TP09MY16.276
And x is the sample mean; s is the sample standard deviation; n is
the number of samples; and t0.95 is the t statistic for a
95% one-tailed confidence interval with n-1 degrees of freedom (from
appendix A to subpart B of this part).
(2) Alternative efficiency determination methods. In lieu of
testing, a represented value of efficiency or consumption for a basic
model must be determined through the application of an AEDM pursuant to
the requirements of Sec. 429.70 and the provisions of this section,
where:
(i) Any represented value of energy consumption or other measure of
energy use of a basic model for which consumers would favor lower
values must be greater than or equal to the output of the AEDM and less
than or equal to the Federal standard for that basic model; and
(ii) Any represented value of energy efficiency or other measure of
energy consumption of a basic model for which consumers would favor
higher values must be less than or equal to the output of the AEDM and
greater than or equal to the Federal standard for that basic model.
(3) The representative value of fuel input rate of a basic model
reported in accordance with paragraph (c)(2) of this section must be
either the mean of the fuel input rate(s) measured for each tested unit
of the basic model and determined in accordance with the test procedure
in Sec. 431.106 of this chapter, or the value determined with an AEDM,
and rounded to the nearest 1,000 Btu/h.
(c) Certification reports. For commercial water heating equipment
other than residential-duty commercial water heaters:
(1) The requirements of Sec. 429.12 apply; and
(2) Pursuant to Sec. 429.12(b)(13), a certification report must
include the following public equipment-specific information:
(i) Commercial electric storage water heaters: The standby loss in
percent per hour (%/h) and the measured storage volume in gallons
(gal).
(ii) Commercial gas-fired and oil-fired storage water heaters: The
thermal efficiency in percent (%), the standby loss in British thermal
units per hour (Btu/h), the rated storage volume in gallons (gal), and
the fuel input rate in British thermal units per hour (Btu/h) rounded
to the nearest 1,000 Btu/h.
(iii) Commercial water heaters and hot water supply boilers with
storage capacity greater than 140 gallons: The thermal efficiency in
percent (%), whether the storage volume is greater than 140 gallons
(Yes/No); whether the tank surface area is insulated with at least R-
12.5 (Yes/No); whether a standing pilot light is used (Yes/No); for gas
or oil-fired water heaters, whether the basic model has a fire damper
or fan-assisted combustion (Yes/No); and, if applicable, pursuant to 10
CFR 431.110, the standby loss in British thermal units per hour (Btu/h)
and measured storage volume in gallons (gal).
(iv) Commercial gas-fired and oil-fired instantaneous water heaters
with storage capacity greater than or equal to 10 gallons and gas-fired
and oil-fired hot water supply boilers with storage capacity greater
than or equal to 10 gallons: The thermal efficiency in percent (%), the
standby loss in British thermal units per hour (Btu/h); the rated
storage volume in gallons (gal); the fuel input rate in British thermal
units per hour (Btu/h) rounded to the nearest 1,000 Btu/h; whether a
submerged heat exchanger is used (Yes/No); and whether flow through the
water heater is required to initiate burner ignition (Yes/No).
(v) Commercial gas-fired and oil-fired instantaneous water heaters
with storage capacity less than 10 gallons and gas-fired and oil-fired
hot water supply boilers with storage capacity less than 10 gallons:
The thermal efficiency in percent (%), the rated storage volume in
gallons (gal), and the fuel input rate in British thermal units per
hour (Btu/h) rounded to the nearest 1,000 Btu/h.
(vi) Commercial unfired hot water storage tanks: The thermal
insulation (i.e., R-value) and stored volume in gallons (gal).
(3) Pursuant to Sec. 429.12(b)(13), a certification report must
include the following additional, equipment-specific information:
(i) Whether the basic model is engineered-to-order; and
(ii) For any basic model rated with an AEDM, whether the
manufacturer elects the witness test option for verification testing.
(See Sec. 429.70(c)(5)(iii) for options.) However, the manufacturer
may not select more than 10 percent of AEDM-rated basic models to be
eligible for witness testing.
(4) Pursuant to Sec. 429.12(b)(13), a certification report may
include supplemental testing instructions in PDF format. If necessary
to run a valid test, the equipment-specific, supplemental information
must include any additional testing and testing set-up instructions
(e.g., whether a bypass loop was used for testing) for the basic model
and all other information (e.g., operational codes or overrides for the
control settings) necessary to operate the
[[Page 28636]]
basic model under the required conditions specified by the relevant
test procedure. A manufacturer may also include with a certification
report other supplementary items in PDF format for DOE's consideration
in performing testing under subpart C of this part. For example, for
gas-fired commercial water heating equipment (other than residential-
duty commercial water heaters): The maximum water pressure in pounds
per square inch (psi), and the minimum and maximum gas supply pressure
in inches of water column (in. w.c.)--including the gas pressure
specifications for both natural gas and propane, if models powered by
both natural gas and propane are certified under the same basic model;
or for oil-fired commercial water heating equipment (other than
residential-duty commercial water heaters): The maximum water pressure
in pounds per square inch (psi), the allowable range for CO2
reading in percent (%), and the fuel pump pressure in pounds per square
inch gauge (psig); or for electric commercial water heating equipment
(other than residential-duty commercial water heaters): The maximum
water pressure in pounds per square inch (psi).
(d) [Reserved]
(e) Alternative methods for determining efficiency or energy use
for commercial water heating equipment can be found in Sec. 429.70.
0
3. Section 429.134 is amended by adding paragraph (m) to read as
follows:
Sec. 429.134. Product-specific enforcement provisions.
* * * * *
(m) Commercial water heating equipment other than residential-duty
commercial water heaters--(1) Verification of fuel input rate. The fuel
input rate of each tested unit of the basic model will be measured
pursuant to the test requirements of Sec. 431.106 of this chapter. The
measured fuel input rate (either the measured fuel input rate for a
single unit sample or the average of the measured fuel input rates for
a multiple unit sample) will be compared to the value of fuel input
rate certified by the manufacturer. The certified fuel input rate will
be considered valid only if the measured fuel input rate is within two
percent of the certified fuel input rate.
(i) If the certified fuel input rate is found to be valid, then the
certified fuel input rate will serve as the basis for determination of
the appropriate equipment class and calculation of the standby loss
standard (as applicable).
(ii) If the measured fuel input rate is not within two percent of
the certified fuel input rate, attempt to achieve the certified fuel
input rate (within two percent), DOE will first attempt to increase or
decrease the gas pressure within the range specified in manufacturer's
instructions in the installation and operation manual shipped with the
commercial water heating equipment being tested or in supplemental
instructions provided by the manufacturer. If the gas pressure range is
not specified by the manufacturer in either of these sources, DOE will
use the default range for gas pressure included in appendices A, C, and
E to subpart G of part 431 of this chapter. If the measured fuel input
rate is still not within two percent of the certified fuel input rate,
DOE will attempt to modify the gas inlet orifice. If the measured fuel
input rate still is not within two percent of the certified fuel input
rate, the measured fuel input rate will serve as the basis for
determination of the appropriate equipment class and calculation of the
standby loss standard (as applicable).
(2) [Reserved]
PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS
0
4. The authority citation for part 430 continues to read as follows:
Authority: 42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.
0
5. Section 430.2 is amended by:
0
a. Removing the definitions of ``Electric heat pump water heater'' and
``Gas-fired heat pump water heater''; and
0
b. Revising the definitions of ``Electric instantaneous water heater,''
``Electric storage water heater,'' ``Gas-fired instantaneous water
heater,'' ``Gas-fired storage water heater,'' ``Oil-fired instantaneous
water heater,'' and ``Oil-fired storage water heater.''
The revisions read as follows:
Sec. 430.2 Definitions.
* * * * *
Electric instantaneous water heater means a water heater that uses
electricity as the energy source, has a nameplate input rating of 12 kW
or less, and contains no more than one gallon of water per 4,000 Btu
per hour of input.
* * * * *
Electric storage water heater means a water heater that uses
electricity as the energy source, has a nameplate input rating of 12 kW
or less, and contains more than one gallon of water per 4,000 Btu per
hour of input.
* * * * *
Gas-fired instantaneous water heater means a water heater that uses
gas as the main energy source, has a nameplate input rating less than
200,000 Btu/h, and contains no more than one gallon of water per 4,000
Btu per hour of input.
Gas-fired storage water heater means a water heater that uses gas
as the main energy source, has a nameplate input rating of 75,000 Btu/h
or less, and contains more than one gallon of water per 4,000 Btu per
hour of input.
* * * * *
Oil-fired instantaneous water heater means a water heater that uses
oil as the main energy source, has a nameplate input rating of 210,000
Btu/h or less, and contains no more than one gallon of water per 4,000
Btu per hour of input.
Oil-fired storage water heater means a water heater that uses oil
as the main energy source, has a nameplate input rating of 105,000 Btu/
h or less, and contains more than one gallon of water per 4,000 Btu per
hour of input.
* * * * *
PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND
INDUSTRIAL EQUIPMENT
0
6. The authority citation for part 431 continues to read as follows:
Authority: 42 U.S.C. 6291-6317.
0
7. Section 431.102 is amended by:
0
a. Revising the section heading;
0
b. Revising the definitions of ``Hot water supply boiler,''
``Instantaneous water heater,'' ``R-value,'' ``Residential-duty
commercial water heater,'' ``Standby loss,'' and ``Storage water
heater'';
0
c. Adding, in alphabetical order, definitions for the terms ``Air-
source commercial heat pump water heater,'' ``Coefficient of
performance,'' ``Commercial heat pump water heater,'' ``Direct geo-
exchange commercial heat pump water heater,'' ``Flow-activated
instantaneous water heater,'' ``Fuel input rate,'' ``Ground water-
source commercial heat pump water heater,'' ``Indoor water-source
commercial heat pump water heater,'' and ``Storage-type instantaneous
water heater''; and
0
d. Removing the definitions of ``ASTM-D-2156-80'' and ``Packaged
boiler.''
The revisions and additions read as follows:
Sec. 431.102 Definitions concerning commercial water heaters, hot
water supply boilers, unfired hot water storage tanks, and commercial
heat pump water heaters.
Air-source commercial heat pump water heater means a commercial
heat pump water heater that utilizes surrounding air as the heat
source.
* * * * *
[[Page 28637]]
Coefficient of performance (COPh) means the
dimensionless ratio of the rate of useful heat transfer gained by the
water (expressed in Btu/h), to the rate of electric power consumed
during operation (expressed in Btu/h).
Commercial heat pump water heater (CHPWH) means a water heater that
uses a refrigeration cycle, such as vapor compression, to transfer heat
from a low-temperature source to a higher-temperature sink for the
purpose of heating potable water, and has a rated electric power input
greater than 12 kW. Such equipment includes, but is not limited to,
air-source heat pump water heaters, water-source heat pump water
heaters, and direct geo-exchange heat pump water heaters.
Direct geo-exchange commercial heat pump water heater means a
commercial heat pump water heater that utilizes the earth as a heat
source and allows for direct exchange of heat between the earth and the
refrigerant in the evaporator coils.
Flow-activated instantaneous water heater means an instantaneous
water heater or hot water supply boiler that does not activate the
burner or heating element if no heated water is drawn from the unit.
Fuel input rate means the maximum rate at which gas-fired or oil-
fired CWH equipment uses energy as determined using test procedures
prescribed under Sec. 431.106.
Ground water-source commercial heat pump water heater means a
commercial heat pump water heater that utilizes ground water as the
heat source.
Hot water supply boiler means a packaged boiler (defined in Sec.
431.82) that is industrial equipment and that:
(1) Has a fuel input rate (for gas-fired or oil-fired equipment) or
input rating (for electric equipment) from 300,000 Btu/h to 12,500,000
Btu/h and of at least 4,000 Btu/h per gallon of stored water;
(2) Is suitable for heating potable water; and
(3) Meets either or both of the following conditions:
(i) It has the temperature and pressure controls necessary for
heating potable water for purposes other than space heating; or
(ii) The manufacturer's product literature, product markings,
product marketing, or product installation and operation instructions
indicate that the boiler's intended uses include heating potable water
for purposes other than space heating.
Indoor water-source commercial heat pump water heater means a
commercial heat pump water heater that utilizes indoor water as the
heat source.
Instantaneous water heater means a water heater that uses gas, oil,
or electricity, including:
(1) Gas-fired instantaneous water heaters with a fuel input rate
both greater than 200,000 Btu/h and not less than 4,000 Btu/h per
gallon of stored water;
(2) Oil-fired instantaneous water heaters with a fuel input rate
both greater than 210,000 Btu/h and not less than 4,000 Btu/h per
gallon of stored water; and
(3) Electric instantaneous water heaters with an input capacity
both greater than 12 kW and not less than 4,000 Btu/h per gallon of
stored water.
R-value means the thermal resistance of insulating material as
determined using ASTM Standard Test Method C177-13 or C518-10
(incorporated by reference; see Sec. 431.105) and expressed in
([deg]F[middot]ft\2\[middot]h/Btu).
Residential-duty commercial water heater means any gas-fired
storage, oil-fired storage, or electric instantaneous commercial water
heater that meets the following conditions:
(1) For models requiring electricity, uses single-phase external
power supply;
(2) Is not designed to provide outlet hot water at temperatures
greater than 180[emsp14][deg]F; and
(3) Does not meet any of the following criteria:
------------------------------------------------------------------------
Indicator of non-residential
Water heater type application
------------------------------------------------------------------------
Gas-fired Storage...................... Fuel input rate >105 kBtu/h;
Rated storage volume >120
gallons.
Oil-fired Storage...................... Fuel input rate >140 kBtu/h;
Rated storage volume >120
gallons.
Electric Instantaneous................. Rated input >58.6 kW; Rated
storage volume >2 gallons.
------------------------------------------------------------------------
Standby loss means:
(1) For electric commercial water heating equipment (not including
commercial heat pump water heaters), the average hourly energy required
to maintain the stored water temperature expressed as a percent per
hour (%/h) of the heat content of the stored water above room
temperature and determined in accordance with appendix B, D, or E to
subpart G of part 431 (as applicable), denoted by the term ``S.''
(2) For gas-fired and oil-fired commercial water heating equipment,
the average hourly energy required to maintain the stored water
temperature expressed in British thermal units per hour (Btu/h) based
on a 70[emsp14][deg]F temperature differential between stored water and
ambient room temperature and determined in accordance with appendix A,
C, or E to subpart G of part 431 (as applicable), denoted by the term
``SL''; or
(3) For unfired hot water storage tanks, the average hourly energy
lost from the storage tank when in standby mode expressed in British
thermal units per hour (Btu/h) and determined in accordance with
appendix G to subpart G of part 431, denoted by the term ``SL.''
Storage water heater means a water heater that uses gas, oil, or
electricity to heat and store water within the appliance at a
thermostatically-controlled temperature for delivery on demand,
including:
(1) Gas-fired storage water heaters with a fuel input rate both
greater than 75,000 Btu/h and less than 4,000 Btu/h per gallon of
stored water;
(2) Oil-fired storage water heaters with a fuel input rate both
greater than 105,000 Btu/h and less than 4,000 Btu/h per gallon of
stored water; and
(3) Electric storage water heaters with an input capacity both
greater than 12 kW and less than 4,000 Btu/h per gallon of stored
water.
Storage-type instantaneous water heater means an instantaneous
water heater comprising a storage tank with a submerged heat
exchanger(s) or heating element(s).
* * * * *
Sec. 431.104 [Removed]
0
8. Section 431.104 is removed.
0
9. Section 431.105 is amended by:
0
a. Redesignating paragraph (b) as (c) and revising newly redesignated
paragraph (c); and
0
b. Adding paragraphs (b), (d), and (e).
The revisions and additions read as follows:
Sec. 431.105 Materials incorporated by reference.
* * * * *
(b) AHRI. Air-Conditioning, Heating, and Refrigeration Institute,
2111 Wilson Blvd., Suite 500, Arlington, VA 22201, (703) 524-8800, or
go to www.ahrinet.org.
[[Page 28638]]
(1) GAMA Testing Standard IWH-TS-1, ``Method to Determine
Performance of Indirect-fired Water Heaters,'' March 2003 edition,
sections 4, 5, 6.0, and 6.1, IBR approved for appendix G to this
subpart.
(2) [Reserved]
(c) ANSI. American National Standards Institute, 25 W. 43rd Street,
4th Floor, New York, NY 10036, (212) 642-4900, or go to: http://www.ansi.org.
(1) ANSI Z21.10.3-2015/CSA 4.3-2015 (``ANSI Z21.10.3-2015''),
``Gas-fired Water Heaters, Volume III, Storage Water Heaters with Input
Ratings Above 75,000 Btu Per Hour, Circulating and Instantaneous,''
Annex E.1, approved by ANSI on October 5, 2015, IBR approved for
appendices A, B, C, D, and E to this subpart.
(2) [Reserved]
(d) ASHRAE. American Society of Heating, Refrigerating and Air-
conditioning Engineers, 1791 Tullie Circle NE., Atlanta, GA 30329,
(800) 527-4723, or go to https://www.ashrae.org.
(1) ANSI/ASHRAE Standard 118.1-2012, ``Method of Testing for Rating
Commercial Gas, Electric, and Oil Service Water-Heating Equipment,''
approved by ASHRAE on October 26, 2012 and by ANSI on October 27, 2012,
IBR approved for appendix F to this subpart.
(2) [Reserved]
(e) ASTM. ASTM International, 100 Barr Harbor Drive, P.O. Box C700,
West Conshohocken, PA 19428-2959, (610) 832-9585, or go to http://www.astm.org.
(1) ASTM C177-13, ``Standard Test Method for Steady-State Heat Flux
Measurements and Thermal Transmission Properties by Means of the
Guarded-Hot-Plate Apparatus,'' approved by ASTM on September 15, 2013,
IBR approved for Sec. 431.102.
(2) ASTM C518-10, ``Standard Test Method for Steady-State Thermal
Transmission Properties by Means of the Heat Flow Meter Apparatus,''
approved by ASTM on May 1, 2010, IBR approved for Sec. 431.102.
(3) ASTM D2156-09, ``Standard Test Method for Smoke Density in Flue
Gases from Burning Distillate Fuels,'' approved by ASTM on December 1,
2009 and reapproved by ASTM on October 1, 2013, IBR approved for
appendices A, C, and E to this subpart.
0
10. Section 431.106 is revised to read as follows:
Sec. 431.106 Uniform test method for the measurement of energy
efficiency of commercial water heating equipment.
(a) Scope. This section contains test procedures for measuring,
pursuant to EPCA, the energy efficiency of commercial water heating
equipment.
(b) Testing and calculations. Determine the energy efficiency of
commercial water heating equipment by conducting the applicable test
procedure(s):
(1) Residential-duty commercial water heaters. Test in accordance
with appendix E to subpart B of part 430 of this chapter.
(2) Commercial water heating equipment other than residential-duty
commercial water heaters. Test covered commercial water heating
equipment by following the appropriate test procedures in appendices to
subpart G of this part.
(i) Gas-fired and oil-fired storage water heaters and storage-type
instantaneous water heaters. Test according to appendix A to subpart G
of this part.
(ii) Electric storage water heaters and storage-type instantaneous
water heaters. Test according to appendix B to subpart G of this part.
(iii) Gas-fired and oil-fired instantaneous water heaters and hot
water supply boilers (other than flow-activated instantaneous water
heaters and storage-type instantaneous water heaters). Test according
to appendix C to subpart G of this part.
(iv) Electric instantaneous water heaters (other than flow-
activated instantaneous water heaters and storage-type instantaneous
water heaters). Test according to appendix D to subpart G of this part.
(v) Flow-activated instantaneous water heaters. Test according to
appendix E to subpart G of this part.
(vi) Commercial heat pump water heaters. Test according to appendix
F to subpart G of this part.
(vii) Unfired hot water storage tanks. Test according to appendix G
to subpart G of this part.
Sec. 431.107 [Removed]
0
11. Section 431.107 is removed.
0
12. Add appendix A to subpart G of part 431 to read as follows:
Appendix A to Subpart G of Part 431--Uniform Test Method for the
Measurement of Thermal Efficiency and Standby Loss of Gas-Fired and
Oil-Fired Storage Water Heaters and Storage-Type Instantaneous Water
Heaters
Note: Prior to (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to the energy use or
efficiency of the subject commercial water heating equipment in
accordance with the results of testing pursuant to this appendix or
the procedures in 10 CFR 431.106 that were in place on January 1,
2016. On and after (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to energy use or
efficiency of gas-fired and oil-fired storage water heaters and
storage-type instantaneous water heaters in accordance with the
results of testing pursuant to this appendix to demonstrate
compliance with the energy conservation standards at 10 CFR 431.110.
1. General
Determine the thermal efficiency and standby loss (as
applicable) in accordance with the following sections of this
appendix. Certain sections reference sections of Annex E.1 of ANSI
Z21.10.3-2015 (incorporated by reference; see Sec. 431.105). Where
the instructions contained in the sections below conflict with
instructions in Annex E.1 of ANSI Z21.10.3-2015, the instructions
contained herein control.
2. Test Set-Up
2.1. Placement of Water Heater. A water heater for installation
on combustible floors is to be placed on a \3/4\-inch plywood
platform supported by three 2 x 4-inch runners. If the water heater
is for installation on noncombustible floors, suitable
noncombustible material is to be placed on the platform. When the
use of the platform for a large water heater is not practical, the
water heater may be placed on any suitable flooring. A wall-mounted
water heater is to be mounted to a simulated wall section.
2.2. Heat Trap and Thermocouple Installation. Inlet and outlet
piping must be turned vertically downward from the connections on a
tank-type water heater so as to form heat traps. Thermocouples for
measuring supply and outlet water temperatures must be installed
upstream from the inlet heat trap piping and downstream from the
outlet heat trap piping, respectively, in accordance with Figure 1,
2, or 3 (as applicable) of this section. The total vertical piping
length between the thermocouple sensing location and the connection
port must be equal to 24 inches. For water heaters with vertical
connections, the 24 inches of total vertical piping length is
divided into 6 inches of vertical piping upstream from the turn for
the heat trap and 18 inches downstream from the turn for the heat
trap. For water heaters that have vertical connections (top and
bottom), the total horizontal piping between the connection port and
the thermocouple sensing location must be equal to the distance
between the water heater connection port and the edge of the water
heater plus 2 inches. For water heaters that have horizontal
connections, the total horizontal piping between the water heater
connection port and the temperature sensing location must be equal
to 6 inches. The water heater must meet the requirements shown in
Figure 1, 2, or 3 (as applicable) at all times during the conduct of
the thermal efficiency and standby loss tests. Any factory-supplied
heat traps must be installed per the installation instructions while
ensuring the requirements in Figure 1, 2, or 3 are met. All
dimensions specified in Figure 1, 2, and 3 and in this section are
measured
[[Page 28639]]
from the outer surface of the pipes and water heater outer casing
(as applicable).
BILLING CODE 6450-01-P
[GRAPHIC] [TIFF OMITTED] TP09MY16.277
[[Page 28640]]
[GRAPHIC] [TIFF OMITTED] TP09MY16.278
BILLING CODE 6450-01-C
[[Page 28641]]
2.3. Thermocouples for Measurement of Mean Tank Temperature. For
the standby loss test, install temperature-sensing means inside the
tank for measurement of mean tank temperature according to the
instructions in section f of Annex E.1 of ANSI Z21.10.3-2015
(incorporated by reference; see Sec. 431.105). Calculate the mean
tank temperature as the average of the six installed temperature-
sensing means.
2.4. Piping Insulation. Insulate all water piping external to
the water heater jacket, including heat traps and piping that are
installed by the manufacturer or shipped with the unit, for at least
4 ft of piping length from the connection at the appliance with
material having an R-value not less than
4[emsp14][deg]F[middot]ft\2\[middot]h/Btu. Ensure that the
insulation does not contact any appliance surface except at the
location where the pipe connections penetrate the appliance jacket.
2.5. Temperature and Pressure Relief Valve Insulation. If the
manufacturer has not provided a temperature and pressure relief
valve, one shall be installed and insulated as specified in section
2.4 of this appendix.
2.6. Vent Requirements. Follow the requirements for venting
arrangements specified in section c of Annex E.1 of ANSI Z21.10.3-
2015 (incorporated by reference; see Sec. 431.105).
2.7. Energy Consumption. Install equipment that determines,
within 1 percent:
2.7.1. The quantity and rate of fuel consumed.
2.7.2. The quantity of electricity consumed by factory-supplied
water heater components, and of the test loop recirculating pump, if
used.
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.1.2. Isolate the water heater using a shutoff valve in the
supply line with an expansion tank installed in the supply line
downstream of the shutoff valve. There must be no shutoff means
between the expansion tank and the appliance inlet.
3.1.3. During conduct of the thermal efficiency test, the
temperature of the supply water must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F.
3.2. Gas Supply Pressure for Gas-Fired Equipment. The outlet
pressure of the gas appliance pressure regulator must be within the
range specified by the manufacturer. If the allowable range of gas
supply pressure is not specified by the manufacturer in literature
shipped with the unit or supplemental test report instructions
included with a certification report, then the outlet pressure of
the gas appliance regulator must be within the default range of 4.5
inches water column (in. w.c.) to 10.5 in. w.c. for natural gas-
powered units or 11 in. w.c. to 13 in. w.c. for propane-powered
units. Obtain the higher heating value of the gas burned.
3.3. Ambient Room Temperature. While setting the tank
thermostats and verifying steady-state operation (prior to the
thermal efficiency test), between the first and second cut-outs
prior to the standby loss test, and during the soak-in period,
thermal efficiency test, and standby loss test, maintain the ambient
room temperature at 75[emsp14][deg]F 5[emsp14][deg]F at
all times. Measure the ambient room temperature at 30-second
intervals during these periods. Measure the ambient room temperature
at the vertical mid-point of the water heater and approximately 2
feet from the water heater jacket. Shield the sensor against
radiation. Calculate the average ambient room temperature separately
for the soak-in period, thermal efficiency test, and standby loss
test. During the soak-in period and thermal efficiency and standby
loss tests, the ambient room temperature must not vary by more than
2.0[emsp14][deg]F at any reading from the average
ambient room temperature.
3.4. Test Air Temperature. While verifying steady-state
operation (prior to the thermal efficiency test) and during the
thermal efficiency and standby loss tests, the test air temperature
must not vary by more than 5[emsp14][deg]F from the
ambient room temperature at any reading. Measure the test air
temperature at 30-second intervals during these periods and at a
location within two feet of the air inlet of the water heater. For
units with multiple air inlets, measure the test air temperature at
each air inlet, and maintain the specified tolerance on deviation
from the ambient room temperature at each air inlet. For CWH
equipment without a specific air inlet, measure the test air
temperature within two feet of a location on the water heater where
combustion air is drawn.
3.5. Ambient Humidity. While verifying steady-state operation
(prior to the thermal efficiency test) and during the thermal
efficiency and standby loss tests, maintain the ambient relative
humidity of the test room at 60 percent 5 percent.
Measure the ambient relative humidity at 30-second intervals during
these periods. The ambient relative humidity must be measured at the
same location as the test air temperature. For units with multiple
air inlets, measure the ambient relative humidity at each air inlet,
and maintain 60 percent 5 percent relative humidity at
each air inlet.
3.6. Maximum Air Draft. During the soak-in period, thermal
efficiency test, and standby loss test, the water heater must be
located in an area protected from drafts of more than 50 ft/min from
room ventilation registers, windows, or other external sources of
air movement. Prior to beginning the soak-in period, thermal
efficiency test, and standby loss test, measure the air draft within
three feet of the jacket of the water heater to ensure this
condition is met. Ensure that no other changes that would increase
the air draft are made to the test set up or conditions during the
conduct of the tests.
3.7. Setting the Tank Thermostat. Before starting the required
soak-in period, the thermostat setting must first be obtained by
starting with the water in the system at 70[emsp14][deg]F 2[emsp14][deg]F. The thermostat must then be set so that the
maximum outlet water temperature, after the thermostat reduces the
fuel supply to a minimum, is 140[emsp14][deg]F
5[emsp14][deg]F.
3.8. Additional Requirements for Oil-Fired Equipment.
3.8.1. Venting Requirements. Connect a vertical length of flue
pipe to the flue gas outlet of sufficient height so as to meet the
minimum draft specified by the manufacturer.
3.8.2. Oil Supply. Adjust the burner rate so that the following
conditions are met:
3.8.2.1. The CO2 reading is within the range
specified by the manufacturer;
3.8.2.2. The fuel pump pressure is within 10
percent of manufacturer's specifications;
3.8.2.3. If either the fuel pump pressure or range for
CO2 reading are not specified by the manufacturer in
literature shipped with the unit or supplemental test report
instructions included with a certification report, then a default
value of 100 psig is to be used for fuel pump pressure, and a
default range of 9-12 percent is to be used for CO2
reading; and
3.8.2.4. Smoke in the flue does not exceed No. 1 smoke as
measured by the procedure in ASTM D2156-09 (incorporated by
reference, see Sec. 431.105). To determine the smoke spot number,
connect the smoke measuring device to an open-ended tube. This tube
must project into the flue \1/4\ to \1/2\ of the pipe diameter.
3.8.2.5. For the thermal efficiency test, measure the
CO2 reading and determine the smoke spot number after
steady-state operation has been obtained as determined by no
variation of outlet water temperature in excess of 2[emsp14][deg]F
over a 3-minute period, but before beginning measurements for the
thermal efficiency test. For the standby loss test, measure the
CO2 reading and determine the smoke spot number after the
first cut-out before beginning measurements for the standby loss
test. However, measurement of the CO2 reading and conduct
of the smoke spot test are not required prior to beginning an
efficiency test (i.e., thermal efficiency or standby loss) if no
settings on the water heater have been changed and the water heater
has not been turned off since the end of a previously run efficiency
test.
3.9. Data Collection Intervals. Follow the data recording
intervals specified in the following sections.
3.9.1. Soak-In Period. Measure the air draft, in ft/min, before
beginning the soak-in period. Measure the ambient room temperature,
in [deg]F, every 30 seconds during the soak-in period.
3.9.2. Thermal Efficiency Test. Follow the data recording
intervals specified in Table 3.1 of this section.
[[Page 28642]]
Table 3.1--Data To Be Recorded Before and During the Thermal Efficiency Test
----------------------------------------------------------------------------------------------------------------
Every 30 Every 10
Item recorded Before test seconds \1\ minutes
----------------------------------------------------------------------------------------------------------------
Gas outlet pressure, in w.c.................................. X ............... ...............
Fuel higher heating value, Btu/ft\3\ (gas) or Btu/lb (oil)... X ............... ...............
Oil pump pressure, psig (oil only)........................... X ............... ...............
CO2 reading, % (oil only).................................... X \1\ ............... ...............
Oil smoke spot reading (oil only)............................ X\2\ ............... ...............
Air draft, ft/min............................................ X ............... ...............
Time, minutes/seconds........................................ ............... X ...............
Fuel weight or volume, lb (oil) or ft\3\ (gas)............... ............... ............... X \3\
Supply water temperature, [deg]F............................. ............... X ...............
Outlet water temperature, [deg]F............................. ............... X ...............
Ambient room temperature, [deg]F............................. ............... X ...............
Test air temperature, [deg]F................................. ............... X ...............
Ambient relative humidity, %................................. ............... X ...............
----------------------------------------------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the test, as well as every 30 seconds during
the test.
\2\ The smoke spot test and CO2 reading are not required prior to beginning the thermal efficiency test if no
settings on the water heater have been changed and the water heater has not been turned off since the end of a
previously-run efficiency test (i.e., thermal efficiency or standby loss).
\3\ Fuel and electricity consumption over the course of the entire test must be measured and used in calculation
of thermal efficiency.
3.9.3. Standby Loss Test. Follow the data recording intervals
specified in Table 3.2 of this section. Additionally, the fuel and
electricity consumption over the course of the entire test must be
measured and used in calculation of standby loss.
Table 3.2--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Gas outlet pressure, in w.c........... X ...............
Fuel higher heating value, Btu/ft\3\ X ...............
(gas) or Btu/lb (oil)................
Oil pump pressure, psig (oil only).... X ...............
CO2 reading, % (oil only)............. X \2\ ...............
Oil smoke spot reading (oil only)..... X \2\ ...............
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Mean tank temperature, [deg]F......... ............... X
Ambient room temperature, [deg]F...... ............... X
Test air temperature, [deg]F.......... ............... X
Ambient relative humidity, %.......... ............... X
------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
\2\ The smoke spot test and CO2 reading are not required prior to
beginning the standby loss test if no settings on the water heater
have been changed and the water heater has not been turned off since
the end of a previously-run efficiency test (i.e., thermal efficiency
or standby loss).
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Soak-In Period. Prior to conducting a thermal efficiency test
or standby loss test, a soak-in period must occur, in which the
water heater must sit without any draws taking place for at least 12
hours. Begin the soak-in period after setting the tank thermostats
as specified in section 3.7 of this appendix, and maintain these
settings throughout the soak-in period. However, a soak-in period is
not required prior to beginning an efficiency test (i.e., thermal
efficiency or standby loss) if no settings on the water heater have
been changed and the water heater has not been turned off since the
end of a previously run efficiency test.
6. Thermal Efficiency Test. Conduct the thermal efficiency test
as specified in section j of Annex E.1 of ANSI Z21.10.3-2015
(incorporated by reference; see Sec. 431.105), with the exception
of the provision stipulating the data collection intervals for water
temperatures. Follow the additional provisions in the following
sections:
6.1. Steady-State Conditions. Adjust the water flow rate to a
constant value such that the following conditions are always
satisfied during the test. Once steady-state operation is achieved,
as determined by no variation of the outlet water temperature in
excess of 2[emsp14][deg]F over a 3-minute period, do not change any
settings on the water heating equipment until measurements for the
thermal efficiency test are finished.
6.1.1. The outlet water temperature must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature.
6.1.2. The burner must fire continuously at full firing rate
(i.e., no modulation or cut-outs) for the entire duration of the
thermal efficiency test.
6.2. Determination of Fuel Input Rate. For the thermal
efficiency test, record the fuel consumed at 10-minute intervals.
Calculate the fuel input rate over each 10-minute period using the
equations in section 6.3 of this appendix. The measured fuel input
rates for these 10-minute periods must not vary by more than 2 percent between any two readings. Determine the overall
fuel input rate using the fuel consumption for the entire duration
of the thermal efficiency test. Round the overall fuel input rate to
the nearest 1,000 Btu/h.
6.3. Fuel Input Rate Calculation. To calculate the fuel input
rate, use the following equations:
6.3.1. For gas-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.279
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total fuel flow as metered, ft\3\
[[Page 28643]]
Cs = Correction applied to the heating value of a gas
Hgas, when it is metered at temperature and/or pressure
conditions other than the standard conditions for which the value of
Hgas is based
Hgas = Higher heating value of a gas, Btu/ft\3\
t = Duration of measurement of fuel consumption
6.3.2. For oil-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.280
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total weight of fuel, lb
Hoil = Higher heating value of oil, Btu/lb
t = Duration of measurement of fuel consumption
7. Standby Loss Test
7.1. Begin fuel flow to the main burner(s) and put the appliance
into operation.
7.2. After the first cut-out, allow the water heater to remain
in standby mode. At this point, do not change any settings on the
water heating equipment until measurements for the standby loss test
are finished.
7.3. At the second cut-out, record the time and ambient room
temperature, and begin measuring the fuel and electric consumption.
Record the initial mean tank temperature.
7.4. The duration of the test must be until the first cut-out
that occurs after 24 hours or 48 hours, whichever comes first.
7.5. Immediately after conclusion of the test, record the total
fuel flow and electrical energy consumption, the final ambient room
temperature, the duration of the standby loss test, and the final
mean tank temperature. Calculate the average of the recorded values
of the mean tank temperature and of the ambient air temperatures
taken at each measurement interval, including the initial and final
values.
7.6. Standby Loss Calculation. To calculate the standby loss,
follow the steps given below:
7.6.1. The standby loss expressed as a percentage (per hour) of
the heat content of the stored water above room temperature must be
calculated using the following equation for gas-fired equipment:
[GRAPHIC] [TIFF OMITTED] TP09MY16.281
And using the following equation for oil-fired equipment:
[GRAPHIC] [TIFF OMITTED] TP09MY16.282
Where,
[Delta]T3 = Average value of the mean tank temperature
minus the average value of the ambient room temperature, expressed
in [deg]F
[Delta]T4 = Final mean tank temperature measured at the
end of the test minus the initial mean tank temperature measured at
the start of the test, expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons measured in accordance with section 4 of this appendix
Et = Thermal efficiency of the water heater measured in
accordance with this appendix, expressed in %
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
t = Total duration of the test in hours
Cs= Correction applied to the heating value of a gas H,
when it is metered at temperature and/or pressure conditions other
than the standard conditions for which the value of H is based.
Qs = Total fuel flow as metered, expressed in ft\3\ (gas)
or lb (oil)
H = Higher heating value of fuel, expressed in Btu/ft\3\ (gas) or
Btu/lb (oil)
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the heat
content of the stored water above room temperature
7.6.2. The standby loss expressed in Btu per hour must be
calculated as follows: SL (Btu per hour) = S (% per hour) x 8.25
(Btu/gal-[deg]F) x Measured Volume (gal) x 70 ([deg]F).
0
13. Add appendix B to subpart G of part 431 to read as follows:
Appendix B to Subpart G of Part 431--Uniform Test Method for the
Measurement of Standby Loss of Electric Storage Water Heaters and
Storage-Type Instantaneous Water Heaters
Note: Prior to (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to the energy use or
efficiency of the subject commercial water heating equipment in
accordance with the results of testing pursuant to this appendix or
the procedures in 10 CFR 431.106 that were in place on January 1,
2016. On and after (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to energy use or
efficiency of electric storage water heaters and storage-type
instantaneous water heaters in accordance with the results of
testing pursuant to this appendix to demonstrate compliance with the
energy conservation standards at 10 CFR 431.110.
1. General
Determine the standby loss in accordance with the following
sections of this appendix. Certain sections reference sections of
Annex E.1 of ANSI Z21.10.3-2015 (incorporated by reference; see
Sec. 431.105). Where the instructions contained in the sections
below conflict with instructions in Annex E.1 of ANSI Z21.10.3-2015,
the instructions contained herein control.
2. Test Set-Up
2.1. Placement of Water Heater. A water heater for installation
on combustible floors is to be placed on a \3/4\-inch plywood
platform supported by three 2 x 4-inch runners. If the water heater
is for installation on noncombustible floors, suitable
noncombustible material is to be placed on the platform. When the
use of the platform for a large water heater is not practical, the
water heater may be placed on any suitable flooring. A wall-mounted
water heater is to be mounted to a simulated wall section.
2.2. Heat Trap and Thermocouple Installation. Inlet and outlet
piping must be turned vertically downward from the connections on a
tank-type water heater so as to form heat traps. Thermocouples for
measuring supply and outlet water temperatures must be installed
upstream of the inlet heat trap piping and downstream of the outlet
heat trap, respectively, in accordance with Figure 1, 2, or 3 (as
applicable) presented in section 2.2 of appendix A to this subpart.
The total vertical (upward and downward) piping between the
thermocouples sensing location and the connection port must be 24
inches. For water heaters with vertical connections, the 24 inches
of total vertical piping length is divided into 6 inches of vertical
piping upstream from the turn for the heat trap and 18 inches
downstream from the turn for the
[[Page 28644]]
heat trap. For water heaters that have vertical connections (top and
bottom), the total horizontal piping between the connection port and
the thermocouple sensing location must be equal to the distance
between the water heater connection port and the edge of the water
heater plus 2 inches. For water heaters that have horizontal
connections, the total horizontal piping between the water heater
connection port and the temperature sensing location, must be equal
to 6 inches. The water heater must meet the requirements shown in
either Figure 1, 2, or 3 (as applicable) at all times during the
conduct of the standby loss test. Any factory-supplied heat traps
must be installed per the installation instructions while ensuring
the requirements in Figure 1, 2, or 3 are met. All dimensions
specified in Figure 1, 2, and 3 and in this section are measured
from the outer surface of the pipes and water heater outer casing
(as applicable).
2.3. Thermocouples for Measurement of Mean Tank Temperature.
Install temperature-sensing means inside the tank for measurement of
mean tank temperature according to the instructions in section f of
Annex E.1 of ANSI Z21.10.3-2015 (incorporated by reference; see
Sec. 431.105). Calculate the mean tank temperature as the average
of the six installed temperature-sensing means.
2.4. Piping Insulation. Insulate all water piping external to
the water heater jacket, including heat traps and piping that are
installed by the manufacturer or shipped with the unit, for at least
4 ft of piping length from the connection at the appliance with
material having an R-value not less than
4[emsp14][deg]F[middot]ft\2\[middot]h/Btu. Ensure that the
insulation does not contact any appliance surface except at the
location where the pipe connections penetrate the appliance jacket.
2.5. Temperature and Pressure Relief Valve Insulation. If the
manufacturer has not provided a temperature and pressure relief
valve, one shall be installed and insulated as specified in section
2.4 of this appendix.
2.6. Energy Consumption. Install equipment that determines,
within 1 percent, the quantity of electricity consumed
by factory-supplied water heater components, and of the test loop
recirculating pump, if used.
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.1.2. Isolate the water heater using a shutoff valve in the
supply line with an expansion tank installed in the supply line
downstream of the shutoff valve. There must be no shutoff means
between the expansion tank and the appliance inlet.
3.2. Electrical Supply. Maintain the electrical supply voltage
to within 5 percent of the center of the voltage range
specified on the water heater nameplate.
3.3. Ambient Room Temperature. While setting the tank
thermostats, between the first and second cut-outs prior to the
standby loss test, and during the soak-in period and standby loss
test, maintain the ambient room temperature at 75[emsp14][deg]F
5[emsp14][deg]F at all times. Measure the ambient room
temperature at 30-second intervals during these periods. Measure the
ambient room temperature at the vertical mid-point of the water
heater and approximately 2 feet from the water heater jacket. Shield
the sensor against radiation. Calculate the average ambient room
temperature separately for the soak-in period and the standby loss
test. During the soak-in period and standby loss test, the room
temperature must not vary more than 2.0[emsp14][deg]F
at any reading from the average ambient room temperature.
3.4. Maximum Air Draft. During the soak-in period and standby
loss test, the water heater must be located in an area protected
from drafts of more than 50 ft/min from room ventilation registers,
windows, or other external sources of air movement. Prior to
beginning the soak-in period and standby loss test, measure the air
draft within three feet of the jacket of the water heater to ensure
this condition is met. Ensure that no other changes that would
increase the air draft are made to the test set up or conditions
during the conduct of the tests.
3.5. Setting the Tank Thermostats. Before starting the required
soak-in period, the thermostat setting(s) must first be obtained as
explained in the following sections.
3.5.1. For water heaters with a single thermostat, the
thermostat setting must be obtained by starting with the water in
the system at 70[emsp14][deg]F 2[emsp14][deg]F. The
thermostat must be set so that the maximum mean tank temperature
after cut-out is 140[emsp14][deg]F 5[emsp14][deg]F.
3.5.2. For water heaters with multiple adjustable thermostats,
set the topmost thermostat first to yield a maximum mean water
temperature after cut-out of 140[emsp14][deg]F
5[emsp14][deg]F. Immediately after setting the top thermostat,
sequentially set the lower thermostat(s) from highest to lowest so
that each yields a maximum mean water temperature after cut-out
equal to 140[emsp14][deg]F 5[emsp14][deg]F. When
setting each thermostat (with the exception of the bottommost
thermostat), calculate the mean tank temperature using only the
temperature readings measured at locations higher in the tank than
the heating element corresponding to the thermostat being set. While
setting each thermostat, all thermostats below the thermostat being
tested must be turned off so that no elements below the thermostat
being tested are in operation. When setting the bottommost
thermostat, calculate the mean tank temperature using all tank
thermocouples. After cut-out by all thermostats in the water heater,
the maximum mean tank temperature must be 140[emsp14][deg]F 5[emsp14][deg]F.
3.6. Data Collection Intervals. Follow the data recording
intervals specified in the following sections.
3.6.1. Soak-In Period. Measure the air draft, in ft/min, before
beginning the soak-in period. Measure the ambient room temperature,
in [deg]F, every 30 seconds during the soak-in period.
3.6.2. Standby Loss Test. Follow the data recording intervals
specified in Table 3.1 of this section. Additionally, the
electricity consumption over the course of the entire test must be
measured and used in calculation of standby loss.
Table 3.1--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Mean tank temperature, [deg]F......... ............... X
Ambient room temperature, [deg]F...... ............... X
------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Soak-In Period. Prior to conducting a standby loss test, a
soak-in period must occur, in which the water heater must sit
without any draws taking place for at least 12 hours. Begin the
soak-in period after setting the tank thermostats as specified in
section 3.5 of this appendix, and maintain these settings throughout
the soak-in period.
6. Standby Loss Test
6.1. Initiate normal operation of the water heater.
[[Page 28645]]
6.2. After the first cut-out, allow the water heater to remain
in standby mode. At this point, do not change any settings on the
water heating equipment until measurements for the standby loss test
are finished.
6.3. At the second cut-out, record the time and ambient room
temperature, and begin measuring the electric consumption. Record
the initial mean tank temperature.
6.4. The duration of the test must be until the first cut-out
that occurs after 24 hours or 48 hours, whichever comes first.
6.5. Immediately after conclusion of the test, record the total
electrical energy consumption, the final ambient room temperature,
the duration of the standby loss test, and the final mean tank
temperature. Calculate the average of the recorded values of the
mean tank temperature and of the ambient air temperatures taken at
each measurement interval, including the initial and final values.
6.6. Standby Loss Calculation. To calculate the standby loss,
follow the steps given below:
6.6.1. The standby loss expressed as a percentage (per hour) of
the heat content of the stored water above room temperature must be
calculated using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.283
Where,
[Delta]T3 = Average value of the mean tank temperature
minus the average value of the ambient room temperature, expressed
in [deg]F
[Delta]T4 = Final mean tank temperature measured at the
end of the test minus the initial mean tank temperature measured at
the start of the test, expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons measured in accordance with section 4 of this appendix
Et = Thermal efficiency--assume 98 percent for electric
water heaters with immersed heating elements
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
t = Total duration of the test in hours
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the heat
content of the stored water above room temperature
0
14. Add appendix C to subpart G of part 431 to read as follows:
Appendix C to Subpart G of Part 431--Uniform Test Method for the
Measurement of Thermal Efficiency and Standby Loss of Gas-Fired and
Oil-Fired Instantaneous Water Heaters and Hot Water Supply Boilers
(Other Than Flow-Activated Instantaneous Water Heaters and Storage-Type
Instantaneous Water Heaters)
Note: Prior to (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to the energy use or
efficiency of the subject commercial water heating equipment in
accordance with the results of testing pursuant to this appendix or
the procedures in 10 CFR 431.106 that were in place on January 1,
2016. On and after (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to energy use or
efficiency of gas-fired and oil-fired instantaneous water heaters
and hot water supply boilers (other than flow-activated
instantaneous water heaters and storage-type instantaneous water
heaters) in accordance with the results of testing pursuant to this
appendix to demonstrate compliance with the energy conservation
standards at 10 CFR 431.110.
1. General
Determine the thermal efficiency and standby loss (as
applicable) in accordance with the following sections of this
appendix. Certain sections reference sections of Annex E.1 of ANSI
Z21.10.3-2015 (incorporated by reference; see Sec. 431.105). Where
the instructions contained in the sections below conflict with
instructions in Annex E.1 of ANSI Z21.10.3-2015, the instructions
contained herein control.
2. Test Set-Up
2.1. Placement of Water Heater. A water heater for installation
on combustible floors is to be placed on a \3/4\-inch plywood
platform supported by three 2 x 4-inch runners. If the water heater
is for installation on noncombustible floors, suitable
noncombustible material is to be placed on the platform. When the
use of the platform for a large water heater is not practical, the
water heater may be placed on any suitable flooring. A wall-mounted
water heater is to be mounted to a simulated wall section.
2.2. Test Configuration. Set up the instantaneous water heater
or hot water supply boiler in accordance with Figure 4 of this
section.
[[Page 28646]]
[GRAPHIC] [TIFF OMITTED] TP09MY16.284
2.2.1. If the instantaneous water heater or hot water supply
boiler does not have any external piping, install a supply water
valve within 5 inches of the water heater jacket, and install an
outlet water valve within 10 inches of the water heater jacket. If
the instantaneous water heater or hot water supply boiler includes
external piping assembled at the manufacturer's premises prior to
shipment, install water valves in the supply and outlet piping (as
applicable) within 5 inches of the end of the piping supplied with
the unit.
2.2.2. If the water heater is not able to achieve an outlet
water temperature of 70[emsp14][deg]F 2[emsp14][deg]F
above the supply water temperature at a constant maximum fuel input
rate, a recirculating loop with pump as shown in Figure 4 in section
2.2 of this appendix must be used.
2.2.2.1. If a recirculating loop with a pump is used then ensure
that the inlet water temperature labeled as T5 in Figure
4 in section 2.2 of this appendix, is greater than or equal to
70[emsp14][deg]F and less than or equal to 120[emsp14][deg]F at all
times during the thermal efficiency test and while achieving steady-
state conditions prior to the standby loss test.
2.3. Installation of Temperature-Sensing Means. The temperature-
sensing means must be installed in a manner such that the tip or the
junction of the temperature sensing probe is in the water; less than
or equal to 5 inches away from the outer casing of the equipment
being tested; in the line of the central axis of the water pipe; and
enclosed in a radiation protection shield. Figure 4 in section 2.2
of this appendix shows the placement of the outlet water
temperature-sensing instrument at a maximum distance of 5 inches
away from the surface of the jacket of the equipment being tested.
For water heaters with multiple outlet water connections leaving the
water heater jacket, temperature-sensing means must be installed for
each outlet water connection leaving the water heater in accordance
with the provisions in this section.
2.4. Piping Insulation. Insulate all water piping external to
the water heater jacket, including piping that are installed by the
manufacturer or shipped with the unit, for at least 4 ft of piping
length from the connection at the appliance with material having an
R-value not less than 4[emsp14][deg]F[middot]ft\2\[middot]h/Btu.
Ensure that the insulation does not contact any appliance surface
except at the location where the pipe connections penetrate the
appliance jacket.
2.5. Temperature and Pressure Relief Valve Insulation. If the
manufacturer has not provided a temperature and pressure relief
valve, one shall be installed and insulated as specified in section
2.4 of this appendix.
2.6. Vent Requirements. Follow the requirements for venting
arrangements specified in section c of Annex E.1 of ANSI Z21.10.3-
2015 (incorporated by reference; see Sec. 431.105).
2.7. Energy Consumption. Install equipment that determines,
within 1 percent:
2.7.1. The quantity and rate of fuel consumed.
2.7.2. The quantity of electricity consumed by factory-supplied
water heater components, and of the test loop recirculating pump, if
used.
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.1.2. During conduct of the thermal efficiency test, the
temperature of the supply water must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F.
3.2. Gas Supply Pressure for Gas-Fired Equipment. The outlet
pressure of the gas appliance pressure regulator must be within the
range specified by the manufacturer. If the allowable range of gas
supply pressure is not specified by the manufacturer in literature
shipped with the unit or supplemental test report instructions
included with a certification report, then the outlet pressure of
the gas appliance regulator must be within the default range of 4.5
inches of water column (in. w.c.) to 10.5 in. w.c. for natural gas-
powered units, or 11 in. w.c. to 13 in. w.c. for propane-powered
units. Obtain the higher heating value of the gas burned.
3.3. Ambient Room Temperature. While verifying steady-state
operation (prior to the thermal efficiency test), between the first
and second cut-outs prior to the standby loss test (as applicable),
and during the thermal
[[Page 28647]]
efficiency and standby loss tests (as applicable), maintain the
ambient room temperature at 75[emsp14][deg]F
5[emsp14][deg]F at all times. Measure the ambient room temperature
at 30-second intervals during these periods. Measure the ambient
room temperature at the vertical mid-point of the water heater and
approximately 2 feet from the water heater jacket. Shield the sensor
against radiation. Calculate the average ambient room temperature
separately for the thermal efficiency and standby loss tests (as
applicable). The ambient room temperature must not vary by more than
2.0[emsp14][deg]F at any reading from the average
ambient room temperature.
3.4. Test Air Temperature. While verifying steady-state
operation (prior to the thermal efficiency test) and during the
thermal efficiency and standby loss tests (as applicable), the test
air temperature must not vary by more than 5[emsp14][deg]F from the ambient room temperature at any
reading. Measure the test air temperature at 30-second intervals
during these periods and at a location within two feet of the air
inlet of the water heater. For units with multiple air inlets,
measure the test air temperature at each air inlet, and maintain the
specified tolerance on deviation from the ambient room temperature
at each air inlet. For CWH equipment without a specific air inlet,
measure the test air temperature within two feet of a location on
the water heater where combustion air is drawn.
3.5. Ambient Humidity. While verifying steady-state operation
(prior to the thermal efficiency test) and during the thermal
efficiency and standby loss tests (as applicable), maintain the
ambient relative humidity of the test room at 60 percent 5 percent. Measure the ambient relative humidity at 30-second
intervals during these periods. The ambient relative humidity must
be measured at the same location as the test air temperature. For
units with multiple air inlets, measure the ambient relative
humidity at each air inlet, and maintain 60 percent 5
percent relative humidity at each air inlet.
3.6. Maximum Air Draft. During the thermal efficiency and
standby loss tests (as applicable), the water heater must be located
in an area protected from drafts of more than 50 ft/min from room
ventilation registers, windows, or other external sources of air
movement. Prior to beginning the thermal efficiency and standby loss
tests, measure the air draft within three feet of the jacket of the
water heater to ensure this condition is met. Ensure that no other
changes that would increase the air draft are made to the test set
up or conditions during the conduct of the tests.
3.7. Setting the Thermostat. Before beginning the thermal
efficiency or standby loss tests, the thermostat setting must first
be obtained by starting with the water in the system at
70[emsp14][deg]F 2[emsp14][deg]F. The thermostat must
then be set so that the maximum outlet water temperature, after the
thermostat reduces the fuel supply to a minimum, is
140[emsp14][deg]F 5[emsp14][deg]F.
3.8. Additional Conditions for Units With Multiple Water
Connections. For units with multiple water connections leaving the
water heater, use the following provisions:
3.8.1. The outlet water temperature measured from each
connection leaving the water heater, must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature, and must not differ from any other outlet water
connection by more than 2[emsp14][deg]F during the thermal
efficiency test.
3.8.2. To calculate the outlet water temperature representative
for the entire unit, calculate the average of the outlet water
temperature measured at each connection leaving the water heater
jacket. This average must be taken for each reading recorded by the
data acquisition unit. The outlet water temperature obtained for
each reading must be used for carrying out all calculations for the
thermal efficiency and standby loss tests.
3.9. Additional Requirements for Oil-Fired Equipment.
3.9.1. Venting Requirements. Connect a vertical length of flue
pipe to the flue gas outlet of sufficient height so as to meet the
minimum draft specified by the manufacturer.
3.9.2. Oil Supply. Adjust the burner rate so that the following
conditions are met:
3.9.2.1. The CO2 reading is within the range
specified by the manufacturer;
3.9.2.2. The fuel pump pressure is within 10 percent
of manufacturer's specifications;
3.9.2.3. If either the fuel pump pressure or range for
CO2 reading are not specified by the manufacturer in
literature shipped with the unit or supplemental test report
instructions included with a certification report, then a default
value of 100 psig is to be used for fuel pump pressure, and a
default range of 9-12 percent is to be used for CO2
reading; and
3.9.2.4. Smoke in the flue does not exceed No. 1 smoke as
measured by the procedure in ASTM D2156-09 (incorporated by
reference, see Sec. 431.105). To determine the smoke spot number,
the smoke measuring device shall be connected to an open-ended tube.
This tube must project into the flue \1/4\ to \1/2\ of the pipe
diameter.
3.9.2.5. For the thermal efficiency test, measure the
CO2 reading and determine the smoke spot number after
steady-state operation has been obtained as determined by no
variation of outlet water temperature in excess of 2[emsp14][deg]F
over a 3-minute period, but before beginning measurements for the
thermal efficiency test. For the standby loss test, measure the
CO2 reading and determine the smoke spot number after the
first cut-out before beginning measurements for the standby loss
test. However, measurement of the CO2 reading and conduct
of the smoke spot test are not required prior to beginning an
efficiency test (i.e., thermal efficiency or standby loss) if no
settings on the water heater have been changed and the water heater
has not been turned off since the end of a previously run efficiency
test.
3.10. Data Collection Intervals. Follow the data recording
intervals specified in the following sections.
3.10.1. Thermal Efficiency Test. Follow the data recording
intervals specified in Table 3.1 of this section.
Table 3.1--Data To Be Recorded Before and During the Thermal Efficiency Test
----------------------------------------------------------------------------------------------------------------
Every 30 Every 10
Item recorded Before test seconds \1\ minutes
----------------------------------------------------------------------------------------------------------------
Gas outlet pressure, in w.c.................................. X ............... ...............
Fuel higher heating value, Btu/ft\3\ (gas) or Btu/lb (oil)... X ............... ...............
Oil pump pressure, psig (oil only)........................... X ............... ...............
CO2 reading, % (oil only).................................... X \2\ ............... ...............
Oil smoke spot reading (oil only)............................ X \2\ ............... ...............
Air draft, ft/min............................................ X ............... ...............
Time, minutes/seconds........................................ ............... X ...............
Fuel weight or volume, lb (oil) or ft\3\ (gas)............... ............... ............... X \3\
Supply water temperature, [deg]F............................. ............... X ...............
Outlet water temperature, [deg]F............................. ............... X ...............
Ambient room temperature, [deg]F............................. ............... X ...............
Test air temperature, [deg]F................................. ............... X ...............
Ambient relative humidity, %................................. ............... X ...............
----------------------------------------------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the test, as well as every 30 seconds during
the test.
\2\ The smoke spot test and CO2 reading are not required prior to beginning the thermal efficiency test if no
settings on the water heater have been changed and the water heater has not been turned off since the end of a
previously-run efficiency test (i.e., thermal efficiency or standby loss).
\3\ Fuel and electricity consumption over the course of the entire test must be measured and used in calculation
of thermal efficiency.
[[Page 28648]]
3.10.2. Standby Loss Test. Follow the data recording intervals
specified in Table 3.2 of this section. Additionally, the fuel and
electricity consumption over the course of the entire test must be
measured and used in calculation of standby loss.
Table 3.2--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Gas outlet pressure, in w.c........... X ...............
Fuel higher heating value, Btu/ft\3\ X ...............
(gas) or Btu/lb (oil)................
Oil pump pressure, psig (oil only).... X ...............
CO2 reading, % (oil only)............. X \2\ ...............
Oil smoke spot reading (oil only)..... X \2\ ...............
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Outlet water temperature, [deg]F...... ............... X
Ambient room temperature, [deg]F...... ............... X
Test air temperature, [deg]F.......... ............... X
Ambient relative humidity, %.......... ............... X
------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
\2\ The smoke spot test and CO2 reading are not required prior to
beginning the thermal efficiency test if no settings on the water
heater have been changed and the water heater has not been turned off
since the end of a previously-run efficiency test (i.e., thermal
efficiency or standby loss).
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Thermal Efficiency Test. Conduct the thermal efficiency test
as specified in section j of Annex E.1 of ANSI Z21.10.3-2015
(incorporated by reference; see Sec. 431.105), with the exception
of the provision stipulating the data collection intervals for water
temperatures. Follow the additional provisions in the following
sections:
5.1. Steady-State Conditions. Adjust the water flow rate to a
constant value such that the following conditions are always
satisfied during the test. Once steady-state operation is achieved,
as determined by no variation of the outlet water temperature in
excess of 2[emsp14][deg]F over a 3-minute period, do not change any
settings on the water heating equipment until measurements for the
thermal efficiency test are finished.
5.1.1. The outlet water temperature must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature.
5.1.2. The burner must fire continuously at full firing rate
(i.e., no modulation or cut-outs) for the entire duration of the
thermal efficiency test.
5.2. Determination of Fuel Input Rate. For the thermal
efficiency test, record the fuel consumption at 10-minute intervals.
Calculate the fuel input rate for each 10-minute period using the
equations in section 5.3 of this appendix. The measured fuel input
rates for these 10-minute periods must not vary by more than 2 percent between any two readings. Determine the overall
fuel input rate using the fuel consumption for the entire duration
of the thermal efficiency test. Round the overall fuel input rate to
the nearest 1,000 Btu/h.
5.3. Fuel Input Rate Calculation. To calculate the fuel input
rate, use the following equations:
5.3.1. For gas-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.285
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total fuel flow as metered, ft\3\
Cs = Correction applied to the heating value of a gas
Hgas, when it is metered at temperature and/or pressure
conditions other than the standard conditions for which the value of
Hgas is based
Hgas = Higher heating value of a gas, Btu/ft\3\
t = Duration of measurement of fuel consumption
5.3.2. For oil-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.286
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total weight of fuel, lb
Hoil = Higher heating value of oil, Btu/lb
t = Duration of measurement of fuel consumption
6. Standby Loss Test
6.1. Begin fuel flow to the main burner(s) and put the appliance
into operation. Prior to beginning the standby loss test, the outlet
water temperature must become constant, as indicated by no variation
in excess of 2[emsp14][deg]F over a 3-minute period, unless no
settings on the water heater were changed and the water heater has
not been turned off since the completion of the thermal efficiency
test.
6.2. After ensuring the outlet water temperature is constant or
if no settings on the water heater have been changed and the water
heater has not been turned off since completion of the thermal
efficiency test, turn off the supply water valve(s), the outlet
water valve(s) (installed as per the provisions in section 2.2 of
this appendix), and the water pump simultaneously and ensure that
there is no flow of water through the water heater.
6.3. After the first cut-out, allow the water heater to remain
in standby mode. At this point, do not change any settings on the
water heating equipment until measurements for the standby loss test
are finished.
6.4. At the second cut-out, record the time and ambient room
temperature, and begin measuring the fuel and electric consumption.
Record the initial outlet water temperature.
6.5. The duration of the test must be until the first cut-out
that occurs after 24 hours or 48 hours, whichever comes first.
6.6. Immediately after conclusion of the test, record the total
fuel flow and electrical energy consumption, the final ambient room
temperature, the duration of the standby loss test, and the final
outlet water temperature. Calculate the average of the recorded
values of the outlet water temperature and of the ambient air
temperatures taken at each measurement interval, including the
initial and final values.
6.7. Standby Loss Calculation. To calculate the standby loss,
follow the steps given below:
6.7.1. The standby loss expressed as a percentage (per hour) of
the heat content of the stored water above room temperature must be
calculated using the following equation for gas-fired equipment:
[[Page 28649]]
[GRAPHIC] [TIFF OMITTED] TP09MY16.287
And using the following equation for oil-fired equipment:
[GRAPHIC] [TIFF OMITTED] TP09MY16.288
Where,
[Delta]T3 = Average value of the outlet water temperature
minus the average value of the ambient room temperature, expressed
in [deg]F
[Delta]T4 = Final outlet water temperature measured at
the end of the test minus the initial outlet water temperature
measured at the start of the test, expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons measured in accordance with section 4 of this appendix
Et = Thermal efficiency of the water heater measured in
accordance with this appendix, expressed in %
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
t = Total duration of the test in hours
Cs = Correction applied to the heating value of a gas H,
when it is metered at temperature and/or pressure conditions other
than the standard conditions for which the value of H is based.
Qs = Total fuel flow as metered, expressed in ft\3\ (gas)
or lb (oil)
H = Higher heating value of gas or oil, expressed in Btu/ft\3\ (gas)
or Btu/lb (oil)
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the heat
content of the stored water above room temperature
6.7.2. The standby loss expressed in Btu per hour must be
calculated as follows: SL (Btu per hour) = S (% per hour) x 8.25
(Btu/gal-[deg]F) x Measured Volume (gal) x 70 ([deg]F).
0
15. Add appendix D to subpart G of part 431 to read as follows:
Appendix D to Subpart G of Part 431--Uniform Test Method for the
Measurement of Standby Loss of Electric Instantaneous Water Heaters
(Other Than Flow-Activated Instantaneous Water Heaters and Storage-Type
Instantaneous Water Heaters)
Note: Prior to (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to the energy use or
efficiency of the subject commercial water heating equipment in
accordance with the results of testing pursuant to this appendix or
the procedures in 10 CFR 431.106 that were in place on January 1,
2016. On and after (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to energy use or
efficiency of electric instantaneous water heaters (other than flow-
activated instantaneous water heaters and storage-type instantaneous
water heaters) in accordance with the results of testing pursuant to
this appendix to demonstrate compliance with the energy conservation
standards at 10 CFR 431.110.
1. General
Determine the standby loss (as applicable) in accordance with
the following sections of this appendix. Certain sections reference
sections of Annex E.1 of ANSI Z21.10.3-2015 (incorporated by
reference; see Sec. 431.105). Where the instructions contained in
the sections below conflict with instructions in Annex E.1 of ANSI
Z21.10.3-2015, the instructions contained herein control.
2. Test Set-Up
2.1. Placement of Water Heater. A water heater for installation
on combustible floors is to be placed on a \3/4\-inch plywood
platform supported by three 2 x 4-inch runners. If the water heater
is for installation on noncombustible floors, suitable
noncombustible material is to be placed on the platform. When the
use of the platform for a large water heater is not practical, the
water heater may be placed on any suitable flooring. A wall-mounted
water heater is to be mounted to a simulated wall section.
2.2. Test Configuration. Set up the water heater in accordance
with Figure 4 in section 2.2 of appendix C to this subpart.
2.2.1. If the instantaneous water heater or hot water supply
boiler does not have any external piping, install a supply water
valve within 5 inches of the water heater jacket, and install an
outlet water valve within 10 inches of the water heater jacket. If
the instantaneous water heater or hot water supply boiler includes
external piping assembled at the manufacturer's premises prior to
shipment, install water valves in the supply and outlet piping (as
applicable) within 5 inches of the end of the piping supplied with
the unit.
2.2.2. If the water heater is not able to achieve an outlet
water temperature of 70[emsp14][deg]F 2[emsp14][deg]F
above the supply water temperature at a constant maximum fuel (or
electricity) input rate, a recirculating loop with pump as shown in
Figure 4 in section 2.2 of appendix C to this subpart must be used.
2.2.2.1. If a recirculating loop with a pump is used then ensure
that the inlet water temperature labeled as T5 in Figure
4 in section 2.2 of appendix C to this subpart, is greater than or
equal to 70[emsp14][deg]F and less than or equal to
120[emsp14][deg]F at all times while achieving steady-state
conditions prior to the standby loss test.
2.3. Installation of Temperature-Sensing Means. The temperature-
sensing means must be installed in a manner such that the tip or the
junction of the temperature sensing probe is in the water; less than
or equal to 5 inches away from the outer casing of the equipment
being tested; in the line of the central axis of the water pipe; and
enclosed in a radiation protection shield. Figure 4 in section 2.2
of appendix C to this subpart shows the placement of the outlet
water temperature-sensing instrument at a maximum distance of 5
inches away from the surface of the jacket of the equipment being
tested. For water heaters with multiple outlet water connections
leaving the water heater jacket, temperature-sensing means must be
installed for each outlet water connection leaving the water heater
in accordance with the provisions in this section.
2.4. Piping Insulation. Insulate all the water piping external
to the water heater jacket, including piping that are installed by
the manufacturer or shipped with the unit, for at least 4 ft of
piping length from the connection at the appliance with material
having an R-value not less than
4[emsp14][deg]F[middot]f\t2\[middot]h/Btu. Ensure that the
insulation does not contact any appliance surface except at the
location where the pipe connections penetrate the appliance jacket.
2.5. Temperature and Pressure Relief Valve Insulation. If the
manufacturer has not provided a temperature and pressure relief
valve, one shall be installed and insulated as specified in section
2.4 of this appendix.
2.6. Energy Consumption. Install equipment that determines,
within 1 percent, the quantity of electricity consumed
by factory-supplied water heater components, and of the test loop
recirculating pump, if used.
[[Page 28650]]
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.2. Electrical Supply. Maintain the electrical supply voltage
to within 5 percent of the center of the voltage range
specified on the water heater nameplate.
3.3. Ambient Room Temperature. Between the first and second cut-
outs prior to the standby loss test and during the standby loss
test, maintain the ambient room temperature at 75[emsp14][deg]F
5[emsp14][deg]F at all times. Measure the ambient room
temperature at 30-second intervals during these periods. Measure the
ambient room temperature at the vertical mid-point of the water
heater and approximately 2 feet from the water heater jacket. Shield
the sensor against radiation. Calculate the average ambient room
temperature for the standby loss test. The ambient room temperature
must not vary more than 2.0[emsp14][deg]F at any
reading from the average ambient room temperature.
3.4. Maximum Air Draft. During the standby loss test, the water
heater must be located in an area protected from drafts of more than
50 ft/min from room ventilation registers, windows, or other
external sources of air movement. Prior to beginning the standby
loss test, measure the air draft within three feet of the jacket of
the water heater to ensure this condition is met. Ensure that no
other changes that would increase the air draft are made to the test
set up or conditions during the conduct of the tests.
3.5. Setting the thermostat. Before beginning the standby loss
test, the thermostat setting must first be obtained by starting with
the water in the system at 70[emsp14][deg]F
2[emsp14][deg]F. While setting the thermostat, ensure that all
heating elements are constantly operating. The thermostat must then
be set so that the maximum outlet water temperature after cut-out is
140[emsp14][deg]F 5[emsp14][deg]F.
3.6. Additional Conditions for Units with Multiple Outlet Water
Connections. For units with multiple outlet water connections
leaving the water heater, use the following provisions:
3.6.1. The outlet water temperature measured from each
connection leaving the water heater prior to conducting the standby
loss test must be maintained at 70[emsp14][deg]F
2[emsp14][deg]F above the supply water temperature, and must not
differ from any other outlet water connection by more than
2[emsp14][deg]F prior to starting the standby loss test.
3.6.2. To calculate the outlet water temperature representative
for the entire unit, calculate the average of the outlet water
temperature measured at each connection leaving the water heater
jacket. This average must be taken for each reading recorded by the
data acquisition unit. The outlet water temperature obtained for
each reading must be used for carrying out all calculations for the
standby loss test.
3.7. Data Collection Intervals. During the standby loss test,
follow the data recording intervals specified in Table 3.1 of this
section. Also, the electricity consumption over the course of the
entire test must be measured and used in calculation of standby
loss.
Table 3.1--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Outlet water temperature, [deg]F...... ............... X
Ambient room temperature, [deg]F...... ............... X
------------------------------------------------------------------------
Note:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Standby Loss Test
5.1. Initiate normal operation of the water heater. Prior to
beginning the standby loss test, the outlet water temperature must
become constant, as indicated by no variation in excess of
2[emsp14][deg]F over a 3-minute period.
5.2. After ensuring the outlet water temperature is constant,
turn off the supply water valve(s), the outlet water valve(s)
(installed as per the provisions in section 2.2 of this appendix),
and the water pump simultaneously and ensure that there is no flow
of water through the water heater.
5.3. After the first cut-out, allow the water heater to remain
in standby mode. At this point, do not change any settings on the
water heating equipment until measurements for the standby loss test
are finished.
5.4. At the second cut-out, record the time and ambient room
temperature, and begin measuring the electric consumption. Record
the initial outlet water temperature.
5.5. The duration of the test must be until the first cut-out
that occurs after 24 hours or 48 hours, whichever comes first.
5.6. Immediately after conclusion of the test, record the total
electrical energy consumption, the final ambient room temperature,
the duration of the standby loss test, and the final outlet water
temperature. Calculate the average of the recorded values of the
outlet water temperature and of the ambient air temperatures taken
at each measurement interval, including the initial and final
values.
5.7. Standby Loss Calculation. To calculate the standby loss,
follow the steps given below:
5.7.1. The standby loss expressed as a percentage (per hour) of
the heat content of the stored water above room temperature must be
calculated using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.289
Where,
[Delta]T3 = Average value of the outlet water temperature
minus the average value of the ambient room temperature, expressed
in [deg]F
[Delta]T4 = Final outlet water temperature measured at
the end of the test minus the initial outlet water temperature
measured at the start of the test, expressed in [deg]F
k = 8.25 Btu/gallon[middot][deg]F, the nominal specific heat of
water
Va = Volume of water contained in the water heater in
gallons measured in accordance with section 4 of this appendix
Et = Thermal efficiency--assume 98 percent for electric
water heaters with immersed heating elements
Ec = Electrical energy consumed by the water heater
during the duration of the test in Btu
t = Total duration of the test in hours
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the heat
content of the stored water above room temperature
16. Add appendix E to subpart G of part 431 to read as follows:
[[Page 28651]]
Appendix E to Subpart G of Part 431--Uniform Test Method for the
Measurement of Thermal Efficiency and Standby Loss of Flow-Activated
Instantaneous Water Heaters
Note: Prior to (date 360 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to the energy use or
efficiency of the subject commercial water heating equipment in
accordance with the results of testing pursuant to this appendix or
the procedures in 10 CFR 431.106 that were in place on January 1,
2016. On and after (date 30 days after date of publication of the
test procedure final rule in the Federal Register), manufacturers
must make any representations with respect to energy use or
efficiency of flow-activated instantaneous water heaters in
accordance with the results of testing pursuant to this appendix to
demonstrate compliance with the energy conservation standards at 10
CFR 431.110.
1. General
Determine the thermal efficiency and standby loss (as
applicable) in accordance with the following sections of this
appendix. Certain sections reference sections of Annex E.1 of ANSI
Z21.10.3-2015 (incorporated by reference; see Sec. 431.105). Where
the instructions contained in the sections below conflict with
instructions in Annex E.1 of ANSI Z21.10.3-2015, the instructions
contained herein control.
2. Test Set-Up
2.1. Placement of Water Heater. Place a water heater for
installation on combustible floors on a \3/4\-inch plywood platform
supported by three 2 x 4-inch runners. If the water heater is for
installation on noncombustible floors, place suitable noncombustible
material on the platform. When the use of the platform for a large
water heater is not practical, the water heater may be placed on any
suitable flooring. Mount a wall-mounted water heater to a simulated
wall section.
2.2. Test Configuration. Set up the instantaneous water heater
in accordance with Figure 4 in section 2.2 of appendix C to this
subpart.
2.2.1. If the instantaneous water heater does not have any
external piping, install a supply water valve within 5 inches of the
water heater jacket, and install an outlet water valve within 10
inches of the water heater jacket. If the instantaneous water heater
or hot water supply boiler includes external piping assembled at the
manufacturer's premises prior to shipment, install water valves in
the supply and outlet piping (as applicable) within 5 inches of the
end of the piping supplied with the unit.
2.2.2. If the water heater is not able to achieve an outlet
water temperature of 70[emsp14][deg]F 2[emsp14][deg]F
above the supply water temperature at a constant maximum fuel input
rate, a recirculating loop with pump as shown in Figure 4 in
appendix C to this subpart must be used for conducting the tests.
2.2.2.1. If a recirculating loop with a pump is used then ensure
that the inlet water temperature labeled as T5 in Figure
4 in section 2.2 of appendix C to this subpart, is greater than or
equal to 70[emsp14][deg]F and less than or equal to
120[emsp14][deg]F at all times during the thermal efficiency test
and while achieving steady-state conditions prior to the standby
loss test.
2.3. Installation of Temperature-Sensing Means. The temperature-
sensing means must be installed in a manner such that the tip or the
junction of the temperature sensing probe is in the water; less than
or equal to 5 inches away from the outer casing of the equipment
being tested; in the line of the central axis of the water pipe; and
enclosed in a radiation protection shield. Figure 4 in section 2.2
of appendix C to this subpart shows the placement of the outlet
water temperature-sensing instrument at a maximum distance of 5
inches away from the surface of the jacket of the equipment being
tested. For water heaters with multiple outlet water connections
leaving the water heater jacket, temperature-sensing means must be
installed for each outlet water connection leaving the water heater
in accordance with the provisions in this section.
2.4. Piping Insulation. Insulate all water piping external to
the water heater jacket, including piping that are installed by the
manufacturer or shipped with the unit, for at least 4 ft of piping
length from the connection at the appliance with material having an
R-value not less than 4[emsp14][deg]F[middot]ft\2\[middot]h/Btu.
Ensure that the insulation does not contact any appliance surface
except at the location where the pipe connections penetrate the
appliance jacket.
2.5. Temperature and Pressure Relief Valve Insulation. If the
manufacturer has not provided a temperature and pressure relief
valve, one shall be installed and insulated as specified in section
2.4 of this appendix.
2.6. Vent Requirements. Follow the requirements for venting
arrangements specified in section c of Annex E.1 of ANSI Z21.10.3-
2015 (incorporated by reference; see Sec. 431.105).
2.7. Energy Consumption. Install equipment that determines,
within 1 percent:
2.7.1. The quantity and rate of fuel consumed (for gas-fired and
oil-fired equipment).
2.7.2. The quantity of electricity consumed by factory-supplied
water heater components, and of the test loop recirculating pump, if
used.
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.1.2. During conduct of the thermal efficiency test, the
temperature of the supply water must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F.
3.2. Gas Supply Pressure for Gas-Fired Equipment. The outlet
pressure of the gas appliance pressure regulator must be within the
range specified by the manufacturer. If the allowable range of gas
supply pressure is not specified by the manufacturer in literature
shipped with the unit or supplemental test report instructions
included with a certification report, then the outlet pressure of
the gas appliance regulator must be within the default range of 4.5
inches water column (in. w.c.) to 10.5 in w.c. for natural gas-
powered units or 11 in. w.c. to 13 in. w.c. for propane-powered
units. Obtain the higher heating value of the gas burned.
3.3. Ambient Room Temperature. While verifying steady-state
operation (prior to the thermal efficiency test) and during the
thermal efficiency test and standby loss tests (as applicable),
maintain the ambient room temperature at 75[emsp14][deg]F 5[emsp14][deg]F at all times. Measure the ambient room
temperature at 30-second intervals during these periods. Measure the
ambient room temperature at the vertical mid-point of the water
heater and approximately 2 feet from the water heater jacket. Shield
the sensor against radiation. Calculate the average ambient room
temperature separately for the thermal efficiency and standby loss
tests (as applicable). The ambient room temperature must not vary
more than 2.0[emsp14][deg]F at any reading from the
average ambient room temperature.
3.4. Test Air Temperature. While verifying steady-state
operation (prior to the thermal efficiency test) and during the
thermal efficiency test, the test air temperature must not vary by
more than 5[emsp14][deg]F from the ambient room
temperature at any reading. Measure the test air temperature at 30-
second intervals during these periods and at a location within two
feet of the air inlet of the water heater. For units with multiple
air inlets, measure the test air temperature at each air inlet, and
maintain the specified tolerance on deviation from the ambient room
temperature at each air inlet. For CWH equipment without a specific
air inlet, measure the test air temperature within two feet of a
location on the water heater where combustion air is drawn.
3.5. Ambient Humidity. While verifying steady-state operation
(prior to the thermal efficiency test) and during the thermal
efficiency test, maintain the ambient relative humidity of the test
room at 60 percent 5 percent during these periods.
Measure the ambient relative humidity at 30-second intervals during
conduct of the test(s). The ambient relative humidity must be
measured at the same location as the test air temperature. For units
that have multiple air inlets, measure the ambient relative humidity
at each air inlet, and maintain 60 percent 5 percent
relative humidity at each air inlet.
3.6. Maximum Air Draft. During the thermal efficiency and
standby loss tests (as applicable), the water heater must be located
in an area protected from drafts of more than 50 ft/min from room
ventilation registers, windows, or other external sources of air
[[Page 28652]]
movement. Prior to beginning the thermal efficiency and standby loss
tests (as applicable), measure the air draft within three feet of
the jacket of the water heater to ensure this condition is met.
Ensure that no other changes that would increase the air draft are
made to the test set up or conditions during the conduct of the
tests.
3.7. Additional Conditions for Units With Multiple Outlet Water
Connections. For units with multiple outlet water connections
leaving the water heater, use the following provisions:
3.7.1. The outlet water temperature measured from each
connection leaving the water heater must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature and must not differ from any other outlet water
connection by more than 2[emsp14][deg]F during the thermal
efficiency test.
3.7.2. To calculate the outlet water temperature representative
for the entire unit, calculate the average of the outlet water
temperature measured at each connection leaving the water heater
jacket. This average must be taken for each reading recorded by the
data acquisition unit. The outlet water temperature obtained for
each reading must be used for carrying out all calculations for the
thermal efficiency and standby loss tests.
3.8. Additional Requirements for Oil-Fired Equipment.
3.8.1. Venting Requirements. Connect a vertical length of flue
pipe to the flue gas outlet of sufficient height so as to meet the
minimum draft specified by the manufacturer.
3.8.2. Oil Supply. Adjust the burner rate so that the following
conditions are met:
3.8.2.1. The CO2 reading is within the range
specified by the manufacturer;
3.8.2.2. The fuel pump pressure is within 10 percent
of manufacturer's specifications;
3.8.2.3. If either the fuel pump pressure or range for
CO2 reading are not specified by the manufacturer in
literature shipped with the unit or supplemental test report
instructions included with a certification report, then a default
value of 100 psig is to be used for fuel pump pressure, and a
default range of 9-12 percent is to be used for CO2
reading; and
3.8.2.4. Smoke in the flue does not exceed No. 1 smoke as
measured by the procedure in ASTM D2156-09 (incorporated by
reference, see Sec. 431.105). To determine the smoke spot number,
the smoke measuring device shall be connected to an open-ended tube.
This tube must project into the flue \1/4\ to \1/2\ of the pipe
diameter.
3.8.2.5. For the thermal efficiency test, measure the
CO2 reading and determine the smoke spot number after
steady-state operation has been obtained as determined by no
variation of outlet water temperature in excess of 2[emsp14][deg]F
over a 3-minute period, but before beginning measurements for the
thermal efficiency test. However, measurement of the CO2
reading and conduct of the smoke spot test are not required prior to
beginning the thermal efficiency test if no settings on the water
heater have been changed and the water heater has not been turned
off since the end of a previously run thermal efficiency test.
3.9. Data Collection Intervals. Follow the data recording
intervals specified in the following sections.
3.9.1. Thermal Efficiency Test. Follow the data recording
intervals specified in Table 3.1 for gas-fired and oil-fired CWH
equipment.
Table 3.1--Data To Be Recorded Before and During the Thermal Efficiency Test
----------------------------------------------------------------------------------------------------------------
Every 30 Every 10
Item recorded Before test seconds \1\ minutes
----------------------------------------------------------------------------------------------------------------
Gas outlet pressure, in w.c.................................. X ............... ...............
Fuel higher heating value, Btu/ft\3\ (gas) or Btu/lb (oil)... X ............... ...............
Oil pump pressure, psig (oil only)........................... X ............... ...............
CO2 reading, % (oil only).................................... X \2\ ............... ...............
Oil smoke spot reading (oil only)............................ X \2\ ............... ...............
Air draft, ft/min............................................ X ............... ...............
Time, minutes/seconds........................................ ............... X ...............
Fuel weight or volume, lb (oil) or ft\3\ (gas)............... ............... ............... X \3\
Supply water temperature, [deg]F............................. ............... X ...............
Outlet water temperature, [deg]F............................. ............... X ...............
Ambient room temperature, [deg]F............................. ............... X ...............
Test air temperature, [deg]F................................. ............... X ...............
Ambient relative humidity, %................................. ............... X ...............
----------------------------------------------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the test, as well as every 30 seconds during
the test.
\2\ The smoke spot test and CO2 reading are not required prior to beginning the thermal efficiency test if no
settings on the water heater have been changed and the water heater has not been turned off since the end of a
previously-run thermal efficiency test.
\3\ Fuel and electricity consumption over the course of the entire test must be measured and used in calculation
of thermal efficiency.
3.9.2. Standby Loss Test. Follow the data recording intervals
specified in Table 3.2 of this section. Additionally, the fuel and
electricity consumption must be measured over the course of the
entire test and used in calculation of standby loss.
Table 3.2--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Outlet water temperature, [deg]F...... ............... X
Ambient room temperature, [deg]F...... ............... X
------------------------------------------------------------------------
Note:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Thermal Efficiency Test. For gas-fired and oil-fired CWH
equipment, conduct the thermal efficiency test as specified in
section j of Annex E.1 of ANSI Z21.10.3-2015 (incorporated by
reference; see Sec. 431.105), with the exception of the provision
stipulating the data collection intervals for water temperatures.
Additionally, follow the provisions in the following sections:
[[Page 28653]]
5.1. Steady-State Conditions. Adjust the water flow rate to a
constant value such that the following conditions are always
satisfied during the test. Once steady-state operation is achieved,
as determined by no variation of the outlet water temperature in
excess of 2[emsp14][deg]F over a 3-minute period, do not change any
settings on the water heating equipment until measurements for the
thermal efficiency test are finished.
5.1.1. The outlet water temperature must be maintained at
70[emsp14][deg]F 2[emsp14][deg]F above the supply water
temperature.
5.1.2. The burner must fire continuously at full firing rate
(i.e., no modulation or cut-outs) for the entire duration of the
thermal efficiency test.
5.2. Determination of Fuel Input Rate. For the thermal
efficiency test, record the fuel consumption at 10-minute intervals.
Calculate the fuel input rate for each 10-minute period using the
equations in section 5.3 of this appendix. The measured fuel input
rates for these 10-minute periods must not vary by more than 2 percent between any two readings. Determine the overall fuel
input rate using the fuel consumption for the entire duration of the
thermal efficiency test. Round the overall fuel input rate to the
nearest 1,000 Btu/h.
5.3. Fuel Input Rate Calculation. To calculate the fuel input
rate, use the following equations:
5.3.1. For gas-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.290
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total fuel flow as metered, ft\3\
Cs = Correction applied to the heating value of a gas
Hgas, when it is metered at temperature and/or pressure
conditions other than the standard conditions for which the value of
Hgas is based
Hgas = Higher heating value of a gas, Btu/ft\3\
t = Duration of measurement of fuel consumption
5.3.2. For oil-fired CWH equipment, calculate the fuel input
rate using the following equation:
[GRAPHIC] [TIFF OMITTED] TP09MY16.291
Where,
Q = Fuel input rate, expressed in Btu/h
Qs = Total weight of fuel, lb
Hoil = Higher heating value of a gas, Btu/lb
t = Duration of measurement of fuel consumption
6. Standby Loss Test
6.1. Initiate normal operation of the water heater. Prior to
beginning the standby loss test, unless no settings on the water
heater were changed and the water heater has not been turned off
since the completion of the thermal efficiency test, achieve steady-
state conditions for the outlet water temperature using the
following provisions: set the supply water temperature to
70[emsp14][deg]F 2[emsp14][deg]F. Adjust the water flow
rate to attain an outlet water temperature of 70[emsp14][deg]F
2[emsp14][deg]F above the supply water temperature.
Once the outlet water temperature is achieved, maintain the flow
rate such to ensure that the outlet water temperature does not vary
in excess of 2[emsp14][deg]F over a 3-minute period.
6.2. After ensuring the outlet water temperature is constant or
if no settings on the water heater have been changed and the water
heater has not been turned off since completion of the thermal
efficiency test, turn off the supply water valve(s) and the outlet
water valve(s) (installed as per the provisions in section 2.2 of
this appendix), and the water pump simultaneously and ensure that
there is no flow of water through the water heater. Allow the water
heater to cut out. After the burner or heating element cuts out,
start recording the measurements for the standby loss test.
6.3. At this time, record the time as t = 0 and record the
initial outlet water temperature, ambient room temperature, and fuel
and electricity meter readings. Continue to monitor and record the
outlet water temperature, the time elapsed from the start of the
test, and the electricity consumption at 30-second intervals using a
data acquisition system.
6.4. Stop the test when one of the following occurs:
(1) The outlet water temperature decreases by 35[emsp14][deg]F
from the initial outlet temperature within 24 hours from the start
of the test, or
(2) 24 hours has elapsed from the start of the test.
Record the final outlet water temperature, fuel consumed,
electricity consumed, and the time elapsed from the start of the
test.
6.5. Once the test is complete, use the applicable equation to
calculate the standby loss in percent per hour:
For gas-fired equipment:
t = Total duration of the test in hours
Cs = Correction applied to the heating value of a gas H,
when it is metered at temperature and/or pressure conditions other
than the standard conditions upon which the value of H is based.
Qs = Total fuel flow as metered, expressed in ft\3\ (gas)
or lb (oil)
H = Higher heating value of gas or oil, expressed in Btu/ft\3\ (gas)
or Btu/lb (oil)
S = Standby loss, the average hourly energy required to maintain the
stored water temperature expressed as a percentage of the initial
heat content of the stored water above room temperature
6.6. For gas-fired and oil-fired flow-activated instantaneous
water heaters, calculate the standby loss in terms of Btu per hour
as follows:
SL (Btu per hour) = S (% per hour) x 8.25 (Btu/gal-[deg]F) x
Measured Volume (gal) x 70 ([deg]F)
Where, SL refers to the standby loss of the water heater,
defined as the amount of energy required to maintain the stored
water temperature expressed in Btu per hour.
0
17. Add appendix F to subpart G of part 431 to read as follows:
Appendix F to Subpart G of Part 431--Uniform Test Method for the
Measurement of Energy Efficiency of Commercial Heat Pump Water Heaters
Note: On and after (date 360 days after date of publication of
the test procedure final rule in the Federal Register),
manufacturers must make any representations with respect to energy
use or efficiency of commercial heat pump water heaters in
accordance with the results of testing pursuant to this appendix.
1. General. Determine the COPh for CHPWHs using the
test procedure set forth below. Certain sections below reference
ASHRAE 118.1-2012 (incorporated by reference; see Sec. 431.105).
Where the instructions contained below differ from those contained
in ASHRAE 118.1-2012, the sections below control.
2. Definitions and Symbols. The definitions and symbols are as
listed in section 3 of ASHRAE 118.1-2012.
3. Instrumentation. The instruments required for the test are as
described in section 6 of ASHRAE 118.1-2012.
4. Test Set-Up. Follow the provisions described in this section
to install the CHPWH for testing.
4.1. Test set-up and installation instructions
4.1.1. For air-source CHPWHs, set up the unit for testing as per
section 7.1 and Figure 5a in section 7.7.1 of ASHRAE 118.1-2012.
4.1.2. For direct geo-exchange CHPWHs, set up the unit for
testing as per section 7.1 and Figure 5b in section 7.7.2 of ASHRAE
118.1-2012.
4.1.3. For indoor water-source and ground water-source CHPWHs,
set up the unit for testing as per section 7.1 and Figure 5c in
section 7.7.3 of ASHRAE 118.1-2012.
4.2. Use the water piping instructions described in section 7.2
of ASHRAE 118.1-2012 and the special instructions described in
section 7.7.6 of ASHRAE 118.1-2012. Insulate all the pipes used for
connections with material having a thermal resistance of not less
than 4 h[middot][deg]F[middot]ft\2\/Btu for a total piping length of
not less than 4 feet from the water heater connection ports.
4.3. Install the thermocouples, including the room
thermocouples, as per the instructions in sections 7.3.2 and 7.3.3
of ASHRAE 118.1-2012.
4.4. Section 7.6 of ASHRAE 118.1-2012 must be used if the
manufacturer neither submits nor specifies a water pump applicable
for the unit for laboratory testing.
4.5. Install the temperature sensors at the locations specified
in Figure 5a, 5b, or 5c as applicable as per section 4.1 of this
appendix. The sensor shall be installed in such a manner that the
sensing portion of the device is positioned within the water flow
and as close as possible to the center line of the pipe. Follow the
instructions provided in sections 7.7.7.1 and 7.7.7.2 of ASHRAE
118.1-2012 to install the temperature and flow-sensing instruments.
4.6. Use the following evaporator side rating conditions as
applicable for each category of CHPWHs. These conditions are also
mentioned in Table 4 of this appendix:
[[Page 28654]]
4.6.1. For air-source CHPWHs, maintain the evaporator air
entering dry-bulb temperature at 80.6 [deg]F 1 [deg]F
and wet-bulb temperature at 71.2 [deg]F 1 [deg]F
throughout the conduct of the test.
4.6.2. For direct geo-exchange CHPWHs, maintain the evaporator
refrigerant temperature at 32[emsp14][deg]F 1 [deg]F.
4.6.3. For indoor water-source CHPWHs, maintain the evaporator
entering water temperature at 68 [deg]F 1 [deg]F.
4.6.4. For ground water-source CHPWHs, maintain the evaporator
entering water temperature at 50 [deg]F 1 [deg]F.
4.7. The CHPWH being tested must be installed as per the
instructions specified in sections 4.1 to 4.6 (as applicable) of
this appendix. For all other installation requirements, use section
7.7.4 of ASHRAE 118.1-2012 to resolve any issues related to
installation (other than what is specified in this test procedure)
of the equipment for testing. Do not make any alterations to the
equipment except as specified in this appendix for installation,
testing, and the attachment of required test apparatus and
instruments.
4.8. Use Table 3 of ASHRAE 118.1-2012 for measurement tolerances
of various parameters.
4.9. If the CHPWH is equipped with a thermostat that is used to
control the throttling valve of the equipment then use the
provisions in section 7.7.7.3 of ASHRAE 118.1-2012 to set up the
thermostat.
5. Test Procedure
Test all CHPWHs as per the provisions described in ASHRAE 118.1-
2012 for ``Type IV'' equipment. Tests for all CHPWH equipment must
follow the steps described below.
5.1. Supply the CHPWH unit with electricity at the voltage
specified by the manufacturer. Follow the provisions in section
8.2.1 of ASHRAE 118.1-2012 to maintain the electricity supply at the
required level.
5.2. Set the condenser supply water temperature and outlet water
temperature per the following provisions and as set forth in Table
5.1 of this section:
Table 5.1--Evaporator and Condenser Side Rating Conditions
------------------------------------------------------------------------
Evaporator side Condenser side
Category of CHPWH rating conditions rating conditions
------------------------------------------------------------------------
Air-source commercial heat Evaporator entering Entering water
pump water heater. air conditions:. temperature: 70
Dry bulb: 80.6 [deg]F
[deg]F 1 [deg]F. Vary
1 [deg]F. water flow rate (if
Wet bulb: 71.2 needed) to achieve
[deg]F the outlet water
1 [deg]F. temperature as
specified in
section 8.7.2 of
ASHRAE 118.1-2012.
If the required
outlet water
temperature as
specified in
section 8.7.2 of
ASHRAE 118.1-2012
is not met even
after varying the
flow rate, then
change the
condenser entering
water temperature
to 110 [deg]F 1 [deg]F.
Vary flow rate to
achieve the
conditions in
section 8.7.2 of
ASHRAE 118.1-2012.
Direct geo-exchange Evaporator Entering water
commercial heat pump water refrigerant temperature: 110
heater. temperature: 32 [deg]F
[deg]F 1 [deg]F.
1 [deg]F.
Indoor water-source Evaporator entering Entering water
commercial heat pump water water temperature: temperature: 110
heater. 68 [deg]F
minus> 1 [deg]F. 1 [deg]F.
Ground water-source Evaporator entering Entering water
commercial heat pump water water temperature: temperature: 110
heater. 50 [deg]F
minus> 1 [deg]F. 1 [deg]F.
------------------------------------------------------------------------
5.2.1. For air-source CHPWHs:
5.2.1.1. Set the supply water temperature to 70 [deg]F 1 [deg]F.
5.2.1.2. Initiate operation at the rated pump flow rate and
measure the outlet water temperature. If the outlet water
temperature is maintained at 120 [deg]F 5 [deg]F with
no variation in excess of 2 [deg]F over a three-minute period, as
required by section 8.7.2 of ASHRAE 118.1-2012, skip to section 5.3
of this appendix.
5.2.1.3. If the outlet water temperature condition as specified
in section 8.7.2 of ASHRAE 118.1-2012 is not achieved, adjust the
water flow rate over the range of the pump's capacity. If, after
varying the water flow rate, the outlet water temperature is
maintained at 120 [deg]F 5 [deg]F with no variation in
excess of 2 [deg]F over a three-minute period, as required by
section 8.7.2 of ASHRAE 118.1-2012, skip to section 5.3 of this
appendix.
5.2.1.4. If, after adjusting the water flow rate within the
range that is achievable by the pump, the outlet water temperature
condition as specified in section 8.7.2 of ASHRAE 118.1-2012 is
still not achieved, then change the supply water temperature to 110
[deg]F 1 [deg]F and repeat the instructions from
sections 5.2.1.2 and 5.2.1.3 of this appendix.
5.2.1.5. If the outlet water temperature condition cannot be
met, then a test procedure waiver is necessary to specify an
alternative set of test conditions.
5.2.2. For direct geo-exchange, indoor water-source, and ground
water-source CHPWHs use the following steps:
5.2.2.1. Set the condenser supply water temperature to 110
[deg]F 1 [deg]F.
5.2.2.2. Follow the steps specified in section 8.7.2 of ASHRAE
118.1-2012 to obtain an outlet water temperature of 120 [deg]F
5 [deg]F with no variation in excess of 2 [deg]F over a
three-minute period.
5.3. Conduct the test as per section 9.1.1, ``Full Input
Rating,'' of ASHRAE 118.1-2012. The flow rate, ``FR,'' referred to
in section 9.1.1 of ASHRAE 118.1-2012 is the flow rate of water
through the CHPWH expressed in gallons per minute obtained after
following the steps in section 5.2 of this appendix. Use the
evaporator side rating conditions specified in section 4.6 of this
appendix to conduct the test as per section 9.1.1 of ASHRAE 118.1-
2012.
5.4. Calculate the COPh of the CHPWH according to
section 10.3.1 of the ASHRAE 118.1-2012 for the ``Full Capacity Test
Method.''
0
18. Add appendix G to subpart G of part 431 to read as follows:
Appendix G to Subpart G of Part 431--Uniform Test Method for the
Measurement of Energy Efficiency of Unfired Hot Water Storage Tanks
Note: On and after (date 360 days after date of publication of
the test procedure final rule in the Federal Register),
manufacturers must make any representations with respect to energy
use or efficiency of unfired hot water storage tanks in accordance
with the results of testing pursuant to this appendix.
1. General
Determine the standby loss in accordance with the following
sections of this appendix. Certain sections reference sections of
GAMA Testing Standard IWH-TS-1 (incorporated by reference; see Sec.
431.105). Where the instructions contained in the sections below
conflict with instructions in GAMA IWH-TS-1, the instructions
contained herein control.
2. Test Set-Up. Set up the unfired hot water storage tank for
testing in accordance with sections 4, 5 (except for section 5.5),
6.0, and 6.1 of GAMA IWH-TS-1.
2.1. Piping Insulation. Insulate all water piping external to
the water heater jacket, including heat traps and piping that are
installed by the manufacturer or shipped with the unit, for at least
4 ft of piping length
[[Page 28655]]
from the connection at the appliance with material having an R-value
not less than 4[emsp14][deg]F[middot]ft\2\[middot]h/Btu. Ensure that
the insulation does not contact any appliance surface except at the
location where the pipe connections penetrate the appliance jacket.
3. Test Conditions
3.1. Water Supply. Follow the following provisions regarding the
water supply to the water heater:
3.1.1. The pressure of the water supply must be maintained
between 40 psi and the maximum pressure specified by the
manufacturer of the unit being tested. If the maximum water pressure
is not specified by the manufacturer in literature shipped with the
unit or supplemental test report instructions included with a
certification report, then a default maximum value of 150 psi is to
be used. The accuracy of the pressure-measuring devices must be
1.0 pounds per square inch (psi).
3.2. Ambient Room Temperature. During the soak-in period and
standby loss test, maintain the ambient room temperature at
75[emsp14][deg]F 5[emsp14][deg]F at all times. Measure
the ambient room temperature at 30-second intervals during these
periods. Measure the average ambient room temperature separately for
the soak-in period and standby loss test. During the soak-in period
and standby loss test, the measured room temperature must not vary
more than 2.0[emsp14][deg]F at any reading from the
average ambient room temperature.
3.3. Maximum Air Draft. During the soak-in period and standby
loss test, the storage tank must be located in an area protected
from drafts of more than 50 ft/min from room ventilation registers,
windows, or other external sources of air movement. Prior to
beginning the soak-in period and standby loss test, measure the air
draft within three feet of the jacket of the water heater to ensure
this condition is met. Ensure that no other changes that would
increase the air draft are made to the test set up or conditions
during conduct of the test.
3.4. Data Collection Intervals. Follow the data recording
intervals specified in the following sections.
3.4.1. Soak-In period. Measure the air draft, in ft/min, before
beginning the soak-in period. Measure the ambient room temperature,
in [deg]F, every 30 seconds during the soak-in period.
3.4.2. Standby Loss Test. Follow the data recording intervals
specified in Table 3.1 of this section.
Table 3.1--Data To Be Recorded Before and During the Standby Loss Test
------------------------------------------------------------------------
Every 30
Item recorded Before test seconds \1\
------------------------------------------------------------------------
Air draft, ft/min..................... X ...............
Time, minutes/seconds................. ............... X
Mean tank temperature, [deg]F......... ............... X
Ambient room temperature, [deg]F...... ............... X
------------------------------------------------------------------------
Notes:
\1\ These measurements are to be recorded at the start and end of the
test, as well as every 30 seconds during the test.
4. Determination of Storage Volume. Determine the storage volume
by subtracting the tare weight--measured while the system is dry and
empty--from the weight of the system when filled with water and
dividing the resulting net weight of water by the density of water
at the measured water temperature.
5. Soak-In Period. Prior to conducting a standby loss test, a
soak-in period must occur, in which the tank must sit without any
draws taking place for at least 12 hours. Begin the soak-in period
after filling the tank with water such that a mean tank temperature
of 145[emsp14][deg]F 5[emsp14][deg]F is achieved.
6. Standby Loss Test
6.1. After conduct of the soak-in period but prior to the start
of the standby loss test, fill the storage tank with water that is
heated sufficiently to achieve a mean tank temperature of at least
145[emsp14][deg]F.
6.2. When the mean tank temperature falls to 142[emsp14][deg]F,
start recording mean tank temperature and ambient room temperature
at regular 30-second intervals as the tank temperature decays.
6.3. When the mean tank temperature falls below
138[emsp14][deg]F, stop the test and record the final mean tank
temperature reading.
6.4. Calculate the standby loss in Btu per hour as follows:
6.4.1. Select the data points starting when the mean tank
temperature first falls to 142[emsp14][deg]F and ending when the
mean tank temperature first falls below 138[emsp14][deg]F. Calculate
the uncorrected decay rate, DRu in [deg]F/h, by a least
squares method as given by:
[GRAPHIC] [TIFF OMITTED] TP09MY16.293
Where:
n = Number of data points collected;
xi = Elapsed time of each data point from the start of
the decay period when the tank first achieves a mean temperature of
142[emsp14][deg]F (hours);
Ti = Mean tank temperature in [deg]F measured at each 30-
second interval during the decay period between the time when the
mean tank temperature first falls to 142[emsp14][deg]F and when the
mean tank temperature drops below 138[emsp14][deg]F.
6.4.2. Calculate the mean tank water temperature decay rate, DR,
in [deg]F/h, as follows:
[GRAPHIC] [TIFF OMITTED] TP09MY16.294
Where Ta is the average ambient room temperature during
the test, [deg]F.
6.4.3. The standby loss, SL, in Btu per hour, for unfired hot
water storage tanks is determined as:
SL = DR x V x [rho] x Cp
Where:
V = tank volume expressed in gallons, measured in accordance with
section 2.4 of this appendix
[rho] = 8.205 pounds per gallon, density of water at
140[emsp14][deg]F
Cp = 0.999 Btu per pound-mass[middot][deg]F, specific
heat of water at 140[emsp14][deg]F.
[FR Doc. 2016-09539 Filed 5-6-16; 8:45 am]
BILLING CODE 6450-01-P
Office of the Federal Register, National Archives and Records Administration
Section
Proposed Rules
Action
Notice of proposed rulemaking (NOPR) and announcement of public meeting.
Dates
Meeting: DOE will hold a public meeting on June 6, 2016, from 9:30 a.m. to 12:00 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.
Contact
Ms. Ashley Armstrong, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Office, EE-5B, 1000 Independence Avenue SW., Washington, DC 20585-0121. Telephone: (202) 586-6590. Email: [email protected] Mr. Eric Stas, U.S. Department of Energy, Office of the General Counsel, GC-33, 1000 Independence Avenue SW., Washington, DC 20585- 0121. Telephone: (202) 586-9507. Email: [email protected]
FR Citation
81
FR
28588
RIN Number
1904-AD18
CFR Citation
10
CFR
429 10
CFR
430 10
CFR
431
CFR Associated
Confidential Business Information; Energy Conservation; Household Appliances; Imports; Reporting and Recordkeeping Requirements; Administrative Practice and Procedure; Intergovernmental Relations; Small Businesses; Incorporation by Reference
and
Test Procedures