[Federal Register Volume 88, Number 106 (Friday, June 2, 2023)]
[Rules and Regulations]
[Pages 36217-36236]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-11341]
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DEPARTMENT OF ENERGY
10 CFR Part 431
[EERE-2019-BT-TP-0041]
RIN 1904-AE57
Energy Conservation Program: Test Procedure for Commercial Warm
Air Furnaces
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Final rule.
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SUMMARY: The U.S. Department of Energy (DOE) is amending the Federal
test procedures for commercial warm air furnaces (CWAFs) to incorporate
the latest versions of the industry test standards that are currently
incorporated by reference. DOE is also establishing a new metric,
Thermal Efficiency Two (TE2), and corresponding test procedure. Use of
the newly established test procedure would become mandatory at such
time as compliance with amended energy conservation standards based on
TE2 is required, should DOE adopt such standards. DOE also is adopting
additional specifications for CWAFs with multiple flue outlets or small
flue outlets.
DATES: The effective date of this rule is July 3, 2023. These
amendments will be mandatory for CWAF equipment testing starting May
28, 2024. The incorporation by reference of certain material listed in
this rule is approved by the Director of the Federal Register on July
3, 2023.
ADDRESSES: The docket, which includes Federal Register notices, public
meeting attendee lists and transcripts, comments, and other supporting
documents/materials, is available for review at www.regulations.gov
under docket number EERE-2019-BT-TP-0041. 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 those containing
information that is exempt from public disclosure.
A link to the docket web page can be found at: www.regulations.gov/docket/EERE-2019-BT-TP-0041. The docket web page contains instructions
on how to access all documents, including public comments, in the
docket.
For further information on how to review the docket, contact the
Appliance and Equipment Standards Program staff at (202) 287-1445 or by
email: [email protected].
FOR FURTHER INFORMATION CONTACT: Ms. Julia Hegarty, 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: (240) 597-6737. 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) 586-5827. Email: [email protected].
SUPPLEMENTARY INFORMATION:
[[Page 36218]]
DOE incorporates by reference the following industry standards into
part 431:
ANSI/AHRI 1500-2015 Performance Rating of Commercial Space Heating
Boilers (``AHRI 1500-2015'');
Copies of AHRI 1500-2015 can be obtained from the Air-Conditioning,
Heating, and Refrigeration Institute (AHRI), 2311 Wilson Blvd., Suite
400, Arlington, VA 22201, (703) 524-8800, or online at:
www.ahrinet.org.
CSA/ANSI Z21.47:21, Gas-fired central furnaces (``ANSI Z21.47-
2021'');
ANSI/ASME PTC 19.3-1974 (R2004), Supplement to ASME Performance
Test Codes: Part 3: Temperature Measurement, Instruments and Apparatus;
ANSI/ASHRAE 103-2022, Method of Testing for Annual Fuel Utilization
Efficiency of Residential Central Furnaces and Boilers (``ASHRAE 103-
2022'');
Copies of ANSI Z21.47-2021, ANSI/ASME PTC 19.3-1974 (R2004) and
ANSI/ASHRAE 103-2022, can be obtained from the American National
Standards Institute (ANSI), 25 W 43rd Street, 4th Floor, New York, NY
10036, (212) 642-4900, or online at: www.webstore.ansi.org.
ASTM D240-09, Standard Test Method for Heat of Combustion of Liquid
Hydrocarbon Fuels by Bomb Calorimeter;
ASTM D396-14a, Standard Specification for Fuel Oils;
ASTM D4809-09a, Standard Test Method for Heat of Combustion of
Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method);
ASTM D5291-10, Standard Test Methods for Instrumental Determination
of Carbon, Hydrogen, and Nitrogen in Petroleum Products and Lubricants;
ASTM E230/E230M-17, Standard Specification for Temperature-
Electromotive Force (emf) Tables for Standardized Thermocouples (``ASTM
E230/E230M-17'');
Copies of ASTM D240-09, ASTM D396-14a, ASTM D4809-09a, ASTM D5291-
10, and ASTM E230/E230M-17 can be obtained from ASTM International, 100
Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428, (877)
909-2786 or online at: www.astm.org.
NFPA 97-2003, Standard Glossary of Terms Relating to Chimneys,
Vents, and Heat-Producing Appliances.
Copies of NFPA 97-2003 can be obtained from the National Fire
Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA 02169-
7471, (1-800-344-3555) or online at: www.nfpa.org.
UL 727, Standard for Safety Oil-Fired Central Furnaces (``UL 727-
2018'');
Copies of UL 727-2018 can be obtained from Underwriters
Laboratories, Inc. (UL), 333 Pfingsten Road, Northbrook, IL 60062,
(847) 272-8800 or online at: www.standardscatalog.ul.com.
For a further discussion of these standards, see section IV.N of
this document.
Table of Contents
I. Authority and Background
A. Authority
B. Background
II. Synopsis of the Final Rule
III. Discussion
A. Scope of Applicability
B. Updates to Industry Standards
1. UL 727
2. HI BTS and AHRI 1500
3. ANSI Z21.47
4. ASHRAE 103
C. ``Thermal Efficiency Two'' Metric
1. Jacket Loss
2. Part-Load Performance
D. Electrical Energy Consumption
E. Other Test Procedure Updates and Clarifications
1. Flue Temperature Measurement in Models With Multiple Flue
Outlets
2. Flue Temperature Measurement in Models With Vent Space
Limitations
3. Flue Loss Determination
4. General Approach
F. Effective and Compliance Dates
G. Test Procedure Costs
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 12866, 13563, and 14094
B. Review Under the Regulatory Flexibility Act
C. Review Under the Paperwork Reduction Act of 1995
D. Review Under the National Environmental Policy Act of 1969
E. Review Under Executive Order 13132
F. Review Under Executive Order 12988
G. Review Under the Unfunded Mandates Reform Act of 1995
H. Review Under the Treasury and General Government
Appropriations Act, 1999
I. Review Under Executive Order 12630
J. Review Under Treasury and General Government Appropriations
Act, 2001
K. Review Under Executive Order 13211
L. Review Under Section 32 of the Federal Energy Administration
Act of 1974
M. Congressional Notification
N. Description of Materials Incorporated by Reference
V. Approval of the Office of the Secretary
I. Authority and Background
CWAFs are included in the list of ``covered equipment'' for which
DOE is authorized to establish and amend energy conservation standards
and test procedures. (42 U.S.C. 6311(1)(J)) DOE's energy conservation
standards and test procedures for CWAFs are currently prescribed at
subpart D of part 431 of title 10 of the Code of Federal Regulations
(CFR). The following sections discuss DOE's authority to establish and
amend test procedures for CWAFs and relevant background information
regarding DOE's consideration of test procedures for this equipment.
A. Authority
The Energy Policy and Conservation Act, as amended (EPCA),\1\ among
other things, authorizes DOE to regulate the energy efficiency of a
number of consumer products and certain industrial equipment. (42
U.S.C. 6291-6317) Title III, Part C \2\ of EPCA, Public Law 94-163 (42
U.S.C. 6311-6317, as codified) added by Public Law 95-619, Title IV,
section 441(a), established the Energy Conservation Program for Certain
Industrial Equipment, which sets forth a variety of provisions designed
to improve energy efficiency. This covered equipment includes CWAFs,
the subject of this final rule. (42 U.S.C. 6311(1)(J))
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\1\ All references to EPCA in this document refer to the statute
as amended through the Energy Act of 2020, Public Law 116-260 (Dec.
27, 2020), which reflect the last statutory amendments that impact
Parts A and A-1 of EPCA.
\2\ For editorial reasons, upon codification in the U.S. Code,
Part C was redesignated Part A-1.
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The energy conservation program under EPCA consists essentially of
four parts: (1) testing, (2) labeling, (3) Federal energy conservation
standards, and (4) certification and enforcement procedures. Relevant
provisions of EPCA include definitions (42 U.S.C. 6311), energy
conservation standards (42 U.S.C. 6313), test procedures (42 U.S.C.
6314), labeling provisions (42 U.S.C. 6315), and the authority to
require information and reports from manufacturers (42 U.S.C. 6316; 42
U.S.C. 6296).
The Federal testing requirements consist of test procedures that
manufacturers of covered equipment must use as the basis for: (1)
certifying to DOE that their equipment complies with the applicable
energy conservation standards adopted pursuant to EPCA (42 U.S.C.
6316(b); 42 U.S.C. 6296), and (2) making other representations about
the efficiency of that equipment (42 U.S.C. 6314(d)). Similarly, DOE
uses these test procedures to determine whether the equipment complies
with relevant standards promulgated under EPCA.
Federal energy efficiency requirements for covered equipment
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6316(a) and 42 U.S.C. 6316(b); 42 U.S.C. 6297) DOE may, however,
grant waivers
[[Page 36219]]
of Federal preemption in limited circumstances for particular State
laws or regulations, in accordance with the procedures and other
provisions of EPCA. (42 U.S.C. 6316(b)(2)(D))
Under 42 U.S.C. 6314, EPCA also sets forth the criteria and
procedures DOE must follow when prescribing or amending test procedures
for covered equipment. Specifically, EPCA requires that any test
procedures prescribed or amended under this section must be reasonably
designed to produce test results which reflect energy efficiency,
energy use or estimated annual operating cost of a given type of
covered equipment (or class thereof) during a representative average
use cycle and requires that test procedures not be unduly burdensome to
conduct. (42 U.S.C. 6314(a)(2))
EPCA requires that the test procedure for CWAFs be those generally
accepted industry testing procedures or rating procedures developed or
recognized by the Air-Conditioning, Heating, and Refrigeration
Institute (AHRI) or by the American Society of Heating, Refrigerating
and Air-Conditioning Engineers (ASHRAE), as referenced in ASHRAE
Standard 90.1, ``Energy Standard for Buildings Except Low-Rise
Residential Buildings'' (ASHRAE Standard 90.1). (42 U.S.C.
6314(a)(4)(A)) Further, if such industry test procedure is amended, DOE
must amend its test procedure to be consistent with the amended
industry test procedure, unless DOE determines, by rule published in
the Federal Register and supported by clear and convincing evidence,
that such amended test procedure would not meet the requirements in 42
U.S.C. 6314(a)(2) and (3) related to representative use and test
burden, in which case DOE may establish an amended test procedure that
does satisfy those statutory provisions. (42 U.S.C. 6314(a)(4)(B) and
(C))
EPCA also requires that, at least once every seven years, DOE
evaluate test procedures for each type of covered equipment, including
CWAFs, to determine whether amended test procedures would more
accurately or fully comply with the requirements for the test
procedures to not be unduly burdensome to conduct and be reasonably
designed to produce test results that reflect energy efficiency, energy
use, and estimated operating costs during a representative average use
cycle. (42 U.S.C. 6314(a)(1)-(3))
In addition, if DOE determines that a test procedure amendment is
warranted, the Department must publish proposed test procedures in the
Federal Register and afford interested persons an opportunity (of not
less than 45 days duration) to present oral and written data, views,
and arguments on the proposed test procedures. (42 U.S.C. 6314(b)) If
DOE determines that test procedure revisions are not appropriate, DOE
must publish in the Federal Register its determination not to amend the
test procedures. (42 U.S.C. 6314(a)(1)(A)(ii)) As discussed further in
section I.B of this document, in January 2023, ASHRAE released the
latest version of ASHRAE Standard 90.1 (ASHRAE Standard 90.1-2022),
which updated the referenced industry standards for testing CWAFs to
reflect the most recent versions of those standards that are currently
available, thereby triggering DOE's rulemaking obligations under EPCA.
DOE is publishing this final rule amending the test procedure for CWAFs
in satisfaction of both the ``ASHRAE trigger'' requirement under 42
U.S.C. 6314(a)(4)(B) and the 7-year-lookback review requirement
specified in EPCA under 42 U.S.C. 6314(a)(1).
B. Background
DOE's current test procedure for CWAFs is codified at 10 CFR
431.76, ``Uniform test method for the measurement of energy efficiency
of commercial warm air furnaces.'' The currently applicable test
procedure incorporates by reference two industry standards for testing
gas-fired CWAFs: American National Standards Institute (ANSI) Z21.47-
2012, ``Standard for Gas-fired Central Furnaces'' (ANSI Z21.47-2012),
which is used for all types of gas-fired CWAFs; and ANSI/American
Society of Heating, Refrigeration, and Air-conditioning Engineers
(ASHRAE) Standard 103-2007, ``Method of Testing for Annual Fuel
Utilization Efficiency of Residential Central Furnaces and Boilers''
(ANSI/ASHRAE 103-2007), which is specifically used for testing
condensing gas-fired CWAFs. 10 CFR 431.76 (c)(1), (d)(2), (e)(1), and
(f)(1); 10 CFR 431.75(b)(1) and (c)(1). The current test procedure also
incorporates by reference two industry standards for testing oil-fired
CWAFs: Hydronics Institute Division of AHRI (HI) BTS-2000 Rev 06.07,
``Method to Determine Efficiency of Commercial Space Heating Boilers''
(HI BTS-2000) \3\ and Underwriters Laboratories (UL) standard UL 727-
2006, ``Standard for Safety Oil-Fired Central Furnaces'' (UL 727-
2006).\4\ 10 CFR 431.76(c)(2), (d)(1), and (e)(2); 10 CFR 471.75(d)(1)
and (e)(2).
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\3\ DOE determined that UL 727-1994 did not provide a procedure
for calculating the percent flue loss of the furnace, which is
necessary in calculating the TE, and, therefore, incorporated by
reference provisions from HI BTS-2000 to calculate the flue loss for
oil-fired CWAFs. 69 FR 61916, 61917, 61940 (Oct. 21, 2004).
\4\ UL 727-1994 is also incorporated by reference in 10 CFR
431.75 but is no longer referenced in the test method specified in
10 CFR 431.76, which references only UL 727-2006.
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DOE most recently amended the test procedure for CWAFs in a final
rule published in the Federal Register on July 17, 2015, which updated
the test procedure for gas-fired CWAFs to incorporate by reference the
latest versions of the industry standards available at the time (i.e.,
ANSI Z21.47-2012 and ANSI/ASHRAE 103-2007). 80 FR 42614 (July 2015
final rule). At the time of the July 2015 final rule, UL 727-2006 and
HI BTS-2000 were still the most recent versions of those industry
standards.
Under EPCA's seven-year-lookback provision, DOE initiated a test
procedure rulemaking for CWAFs by publishing a request for information
(RFI) in the Federal Register on May 5, 2020 (May 2020 RFI). 85 FR
26626. The May 2020 RFI solicited public comments, data, and
information on aspects of the existing DOE test procedure for CWAFs,
including whether there are any issues with the current test procedure
and whether it is in need of updates or revisions. Id.
DOE published a notice of proposed rulemaking (NOPR) for the CWAFs
test procedure in the Federal Register on February 25, 2022 that
presented DOE's proposals to amend that test procedure. 87 FR 10726
(February 2022 NOPR). DOE held a webinar public meeting related to this
NOPR on March 29, 2022. DOE received comments in response to the
February 2022 NOPR from the interested parties listed in Table I.1.
[[Page 36220]]
Table I.1--List of Commenters With Written Submissions or Oral Comments
in Response to the February 2022 NOPR
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Abbreviation used
Commenter(s) in this Final Rule Commenter type
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AAON Inc........................ AAON.............. Manufacturer.
Air-Conditioning, Heating, and AHRI.............. Manufacturer Trade
Refrigeration Institute. Association.
American Gas Association and AGA and APGA...... Utility Trade
American Public Gas Association. Association.
Appliance Standards Awareness Joint Advocates... Efficiency
Project, and Natural Resources Advocacy
Defense Council. Organization.
California Energy Commission.... CEC............... Efficiency
Advocacy
Organization.
Carrier Corporation............. Carrier........... Manufacturer.
Daikin Comfort Technologies Daikin............ Manufacturer.
Manufacturing.
Lennox International Inc........ Lennox............ Manufacturer.
New York State Energy Research NYSERDA........... State Agency.
and Development Authority.
Northwest Energy Efficiency NEEA.............. Efficiency
Alliance. Advocacy
Organization.
Pacific Gas and Electric CA IOUs........... Utilities.
Company, San Diego Gas and
Electric, and Southern
California Edison
(collectively, the ``California
Investor-Owned Utilities'').
Rheem Manufacturing............. Rheem............. Manufacturer.
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A parenthetical reference at the end of a comment quotation or
paraphrase provides the location of the item in the public record.\5\
To the extent that interested parties have provided written comments
that are substantively similar to any oral comments provided during the
March 29, 2022 NOPR webinar public meeting, DOE cites the written
comments throughout this final rule. For the party that provided
substantive oral comments at the March 29, 2022 NOPR webinar public
meeting but did not submit written comments, DOE cites the public
meeting transcript.
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\5\ The parenthetical reference provides a reference for
information located in the docket of DOE's rulemaking to develop
test procedures for CWAFs. (Docket No. EERE-2019-BT-TP-0041, which
is maintained at www.regulations.gov). The references are arranged
as follows: (commenter name, comment docket ID number, page of that
document).
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Since publication of the February 2022 NOPR, DOE would note the
following additional developments which are relevant to this rulemaking
proceeding. As discussed, EPCA requires DOE to use industry test
procedures developed or recognized by AHRI or ASHRAE as referenced in
ASHRAE Standard 90.1. (42 U.S.C. 6314(a)(4)(A)-(B)) The latest update
to ASHRAE Standard 90.1 was released in January 2023 (ASHRAE Standard
90.1-2022). ASHRAE Standard 90.1-2022 references ANSI Z21.47-2021 as
the test method for gas-fired CWAFs and UL 727-2018 as the test method
for oil-fired CWAFs. This action by ASHRAE triggered DOE's rulemaking
obligations under EPCA. As noted previously, in such cases, EPCA
requires DOE to amend the Federal test procedure to be consistent with
these amended industry test procedures, unless DOE determines, by rule
published in the Federal Register and supported by clear and convincing
evidence, that to do so would not meeting the statutory requirements
related to representativeness and not being unduly burdensome. (42
U.S.C. 6314(a)(4)(B)) Furthermore, EPCA also requires that, at least
once every seven years, DOE evaluate test procedures for each class of
covered equipment, including those for CWAFs, to determine whether
amended test procedures would more accurately or fully comply with the
requirements for the test procedures to not be unduly burdensome to
conduct and be reasonably designed to produce test results that reflect
energy efficiency, energy use, and estimated operating costs during a
representative average use cycle. (42 U.S.C. 6314(a)(1)) This
rulemaking satisfies both of these statutory obligations.
II. Synopsis of the Final Rule
In this final rule, DOE is amending its test procedures for CWAFs
as follows:
(1) Reorganize the setup and testing provisions in 10 CFR 431.76
related to the determination of thermal efficiency (TE) into the newly
established 10 CFR part 431, subpart D, appendix A (appendix A);
(2) Incorporate by reference the most recent versions of the
currently referenced industry standards:
UL 727-2018 (previously UL 727-2006) for testing oil-fired
CWAFs;
AHRI 1500-2015 (previously HI BTS-2000) for performing
fuel oil analysis and for calculating flue loss of oil-fired CWAFs;
ANSI Z21.47-2021 (previously ANSI Z21.47-2012) for testing
gas-fired CWAFs; and
ANSI/ASHRAE 103-2022 (previously ANSI/ASHRAE 103-2007) for
testing condensing gas-fired CWAFs;
(3) Incorporate by reference the standards referenced in UL 727-
2018 (i.e., NFPA 97-2003 and ANSI/ASTM E230/230M-17), AHRI 1500-2015
(i.e., ASTM D396-14a, ASTM D240-09, ASTM D4809-09a, and ASTM D5291-10),
and ANSI Z21.47-2021 (i.e., ANSI/ASME PTC 19.3-1974 (R2004)) that are
necessary for performing the DOE test procedure;
(4) Clarify how to test units with multiple flue outlets, and units
with flue outlets having a cross-sectional area of 3.14 square inches
or less; and
(5) Establish a new test procedure at 10 CFR part 431, subpart D,
appendix B (appendix B), which generally requires testing as in
appendix A, but which establishes a new metric, ``TE2.'' The new TE2
metric accounts for jacket losses and part-load operation in addition
to accounting for flue losses. Manufacturers can use appendix B to make
voluntary representations of TE2; representations using this test
procedure are not mandatory until such time as compliance is required
with amended energy conservation standards based on TE2, should DOE
adopt such standards.
The amendments adopted in this final rule are summarized in Table
II.1 compared to the test procedure prior to amendment, as well as the
reason for the change.
[[Page 36221]]
Table II.1--Summary of Changes in the Amended Test Procedure
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DOE test procedure prior to Applicable test
amendment Amended test procedures procedure Attribution
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Referenced UL 727-2006 for testing Incorporate by reference UL appendix A and Align with industry
oil-fired CWAFs. 727-2018 for testing oil- appendix B. standard update.
fired CWAFs, and the
standards referenced in UL
727-2018 that are
necessary in performing
the DOE test procedure
(i.e., NFPA 97-2003 and
ANSI/ASTM E230/E230M-17).
Referenced HI BTS-2000 for Incorporate by reference appendix A and Align with industry
performing fuel oil analysis and AHRI 1500-2015 for appendix B. standard update.
for calculating flue loss of oil- performing fuel oil
fired CWAFs. analysis and for
calculating flue loss of
oil-fired CWAFs and the
standards referenced in
AHRI 1500-2015 that are
necessary in performing
the DOE test procedure
(i.e., ASTM D396-14a, ASTM
D240-09, ASTM D4809-09a,
and ASTM D5291-10).
Referenced ANSI Z21.47-2012 for Incorporate by reference appendix A and Align with industry
testing gas-fired CWAFs. ANSI Z21.47-2021 for appendix B. standard update.
testing gas-fired CWAFs,
and the standards
referenced in ANSI Z21.47-
2021 that are necessary in
performing the DOE test
procedure (i.e., ANSI/ASME
PTC 19.3-1974 (R2004)).
Referenced ANSI/ASHRAE 103-2007 for Incorporate by reference appendix A and Align with industry
testing condensing gas-fired CWAFs. ANSI/ASHRAE 103-2022 for appendix B. standard update.
testing condensing gas-
fired CWAFs.
Did not specify how to test units Adds specifications for appendix A and Additional
with multiple flue outlets. units with multiple flue appendix B. specification to
outlets. Measurements made improve consistency
in each flue outlet shall and repeatability in
be averaged or adjusted testing.
using a weighted average,
depending on the input
capacity of the furnace
module associated with
each flue outlet.
Did not specify how to test units Adds specifications to appendix A and Additional
with flue outlets that are too address units with small appendix B. specification to
small to fit nine thermocouples. flue outlets. Units with improve consistency
flue outlets that are 3.14 and repeatability in
inches or smaller in cross- testing.
sectional area may
optionally use 5
thermocouples.
Efficiency metric (TE) only Establishes a new metric appendix B............ Improve
accounted for flue losses and does (TE2) that accounts for representativeness.
not account for jacket losses or flue losses, jacket
part-load operation. losses, and part-load
operation.
----------------------------------------------------------------------------------------------------------------
DOE has determined that the adopted amendments for the test
procedure at appendix A described in section III of this document will
not alter the measured TE of CWAFs, that the test procedures are not
unduly burdensome to conduct, and that the test procedures more
accurately produce test results that reflect energy efficiency, energy
use, and estimated operating costs of CWAFs during a representative
average use cycle.
DOE has determined that the additional amendments for appendix B,
which adopt TE2 as a new efficiency metric for CWAFs, do alter the
reported efficiency of CWAFs. However, testing in accordance with the
TE2 test procedure is not required until such time as compliance is
required with any amended energy conservation standards based on
appendix B. Prior to such date, voluntary representations of TE2 may be
made, but they must be based upon use of the test procedure in appendix
B.
The amendments adopted in this final rule are discussed in detail
in section III of this document.
The effective date for the amended test procedures adopted in this
final rule is 30 days after publication of this document in the Federal
Register. Representations of energy use or energy efficiency must be
based on testing in accordance with the amended test procedures
beginning 360 days after the date of publication of this final rule in
the Federal Register.
III. Discussion
In the following sections, DOE describes the adopted amendments to
the test procedures for CWAFs. DOE also discusses issues raised by
commenters on the February 2022 NOPR, along with DOE's responses.
A. Scope of Applicability
This rulemaking applies to CWAFs. EPCA defines ``warm air furnace''
as a self-contained oil-fired or gas-fired furnace designed to supply
heated air through ducts to spaces that require it and includes
combination warm air furnace/electric air conditioning units, but does
not include unit heaters and duct furnaces. (42 U.S.C. 6311(11)(A)) DOE
codified the statutory definition of ``warm air furnace'' at 10 CFR
431.72. DOE defines a CWAF as a warm air furnace that is industrial
equipment, and that has a capacity (rated maximum input) of 225,000
British thermal units (Btu) per hour or more. 10 CFR 431.72.
In response to the February 2022 NOPR, NEEA recommended that DOE
expand the scope of CWAF coverage to include 3-phase units with a
capacity less than 225,000 Btu/h. NEEA asserted that failing to do so
would leave a significant portion of the CWAF market unregulated, and
the commenter noted that DOE has recently proposed closing a similar
regulatory gap for 3-phase small commercial air conditioners and heat
pumps and variable refrigerant flow air conditioners and heat pumps
with cooling capacities less than 65,000 btu/h. (NEEA, No. 24 at p. 8)
In response, DOE notes that NEEA made the same recommendation in a
comment submitted in response to a notice of proposed determination
(``NOPD'') for CWAF energy conservation standards that was published in
the Federal Register on April 26, 2022 (April 2022 NOPD). 87 FR 24455
(See Docket No. EERE-2019-BT-STD-0042, comment 34 at p. 6)
Subsequently, in a final determination published in the Federal
Register on December 23, 2022 (December 2022 Final Determination), DOE
declined to
[[Page 36222]]
amend the CWAF definition to include three-phase furnaces with
capacities less than 225,000 Btu/h due to the limited potential to
achieve energy savings from doing so. 87 FR 78821, 78826. DOE maintains
its position from the December 2022 Final Determination that such
equipment represents a small portion of the overall CWAF market, which
at present does not provide an opportunity for significant energy
savings.
B. Updates to Industry Standards
As discussed, prior to the amendments adopted in this final rule,
DOE incorporated by reference in 10 CFR part 431, subpart D, the
following industry test procedures: UL 727-2006, HI-BTS 2000, ANSI
Z21.47-2012, and ANSI/ASHRAE Standard 103-2007. Updated versions of
each of these test standards have been published since they were
incorporated into the DOE test procedure. These updated test standards
are UL 727-2018 (update to UL 727-2006), AHRI 1500-2015 (update to HI-
BTS 2000), ANSI Z21.47-2021 (update to ANSI Z21.47-2016), and ANSI/
ASHRAE Standard 103-2022 \6\ (update to ANSI/ASHRAE Standard 103-2007).
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\6\ The February 2022 TP NOPR proposed to incorporate by
reference ANSI/ASHRAE 103-2017; however, in 2022, ASHRAE published a
more recent version of the standard, ANSI/ASHRAE 103-2022.
---------------------------------------------------------------------------
In the February 2022 NOPR, DOE noted several differences between
versions of the industry standards incorporated by reference at that
time and the more recent versions of the industry standards and sought
comment on these changes. 87 FR 10726, 10730-10735 (Feb. 25, 2022).
Stakeholder comments in response these proposals in the February 2022
NOPR are discussed in the following sections. In response to the
updates to the relevant industry standards, DOE is amending the Federal
test procedure for CWAFs to incorporate by reference in 10 CFR part
431, subpart D, the following updated industry standards: UL 727-2018,
AHRI 1500-2015, ANSI Z21.47-2021, and ANSI/ASHRAE 103-2022.
As discussed, prior to the effective date of the amendments adopted
in this final rule, the DOE test procedure for CWAFs was specified in
10 CFR 431.76. In this final rule, DOE is reorganizing the CWAF test
procedures into two appendixes to subpart D of 10 CFR part 431:
appendix A (using the current TE metric) and appendix B (using the new
TE2 metric). DOE is reorganizing the test procedures in this way
because, as discussed in section III.C of this document, DOE is
establishing appendix B for determining the TE2. In contrast, the
establishment of appendix A is editorial and for reorganization
purposes. DOE has determined that creating separate appendixes for the
determination of the two different metrics would help clarify which
appendix corresponds to which metric. Relevant to both appendices, DOE
is incorporating by reference the industry standards, as discussed in
the following sections.
1. UL 727
The CWAF test procedure, prior to the amendments adopted in this
final rule, required use of those procedures contained in UL 727-2006
that are relevant to the steady-state efficiency measurement (i.e., UL
727-2006 sections 1 through 3; 37 through 42 (except for sections 40.4
and 40.6.2 through 40.6.7); 43.2; and 44 through 46).
In the February 2022 NOPR, DOE proposed to amend the test procedure
to reference UL 727-2018. 87 FR 10726, 10731 (Feb. 25, 2022).
Additionally, DOE proposed to explicitly identify the provisions of UL
727-2018 that are applicable to the DOE test procedure for CWAFs,
because DOE tentatively determined that the scope section of UL 727-
2018 is not applicable since the scope of the DOE test procedure is
defined separately in 10 CFR 431.76(a). Id.
The February 2022 NOPR also discussed that UL 727-2018 has
different language pertaining to temperature measurements and using
potentiometers and thermocouples, and it also incorporates different
ANSI references regarding these topics as compared to UL 727-2006. DOE
tentatively determined that there was not sufficient evidence to
indicate that the updates in UL 727-2018 would not meet the
requirements of EPCA at 42 U.S.C. 6314(a)(2) and (3); therefore, DOE
proposed to also incorporate by reference the updated ANSI standard
(i.e., ANSI/ASTM E230/E230M-17) referenced by UL 727-2018. 87 FR 10726,
10732 (Feb. 25, 2022).
Finally, in the February 2022 NOPR, DOE discussed that UL 727-2018
references NFPA 97M, ``Standard Glossary of Terms Relating to Chimneys,
Gas Vents and Heat Producing Appliances'' (NFPA 97M) for definitions of
the terms ``combustible'' and ``noncombustible'' but does not specify
which version of NFPA 97M. DOE tentatively concluded that NFPA 97M is
an outdated standard and that NFPA 97-2003, ``Standard Glossary of
Terms Relating to Chimneys, Vents, and Heat-Producing Appliances''
(NFPA 97-2003) should be referenced for these definitions instead.
Therefore, DOE proposed to replace references to NFPA 97M in UL 727-
2018 with references to NFPA 97-2003. Id.
DOE received comments from Daikin, Carrier, and AHRI supporting the
proposal to reference NFPA 97-2003 rather than NFPA 97M. (Daikin, No.
25 at p. 1; Carrier, No. 22 at p. 2; AHRI, No. 17 at p. 2) DOE did not
receive any comments in response to the proposals related to
incorporating by reference UL 727-2018.
For the reasons summarized in this document and discussed in the
February 2022 NOPR, DOE is amending the DOE test procedure to
incorporate by reference UL 727-2018, as well as incorporating the
additional industry standards related to UL 727-2018.
2. HI BTS and AHRI 1500
Prior to the amendments adopted in this final rule, DOE's test
procedure for oil-fired CWAFs referenced sections of HI BTS-2000 that
are relevant to fuel oil analysis and calculating percent flue loss
(i.e., HI BTS-2000 sections 8.2.2, 11.1.4, 11.1.5, and 11.1.6.2). (See
10 CFR 431.76(c)(2) and (e)(2) in effect as of January 1, 2022.) DOE's
test procedure included these provisions because DOE previously
determined that UL 727 does not provide a procedure for calculating the
percent flue loss of the furnace, which is necessary in calculating the
TE. Therefore, DOE incorporated by reference provisions from HI BTS-
2000 to calculate the flue loss for oil-fired CWAFs. 69 FR 61916,
61917, 61940 (Oct. 21, 2004).
In the February 2022 NOPR, DOE explained that in 2015, HI BTS-2000
was replaced with AHRI 1500-2015. 87 FR 10726, 10732 (Feb. 25, 2022).
The February 2022 NOPR also discussed that the DOE test procedure
references fuel oil analysis requirements in HI BTS-2000 and that the
fuel oil analysis requirements are different in AHRI 1500-2015. DOE
tentatively determined that the differences would not impact the
performance of a CWAF under test because the fuel oil analysis
requirements in AHRI 1500-2015 are essentially equivalent to those in
HI BTS-2000. As a result, DOE proposed to incorporate by reference AHRI
1500-2015, including its fuel oil analysis specifications. 87 FR 10726,
10733 (Feb. 25, 2022).
In addition, in the February 2022 NOPR DOE noted that section
11.1.4 of HI BTS-2000 requires that the carbon dioxide (CO2)
value used in the calculation of the dry flue gas loss for
[[Page 36223]]
oil must be the measured CO2,\7\ while section C7.2.4 of
AHRI 1500-2015 (previously section 11.1.4 in HI BTS-2000) includes the
option to calculate CO2 using the measured oxygen
(O2) value instead of directly measuring the CO2
value. 87 FR 10726, 10733 (Feb. 25, 2022). DOE tentatively determined
that calculating CO2 using a measured O2 value,
as specified in AHRI 1500-2015, would provide results equivalent to the
CO2 measurement currently required by the DOE test method,
and that allowing a calculated value of CO2 would harmonize
with the latest industry standard without increasing test burden. As
such, DOE proposed to adopt the optional method specified in AHRI 1500-
2015 that allows for calculation CO2 using a measured
O2 value and requested comment on this proposal. Id.
---------------------------------------------------------------------------
\7\ The DOE test procedure at 10 CFR 431.76(d) also states that
CO2 must be measured.
---------------------------------------------------------------------------
AHRI supported the proposal to adopt the optional method specified
in AHRI 1500-2015 that allows for calculation CO2 using a
measured O2 value. (AHRI, No. 17 at p. 2) DOE did not
receive any other comments related to its proposal to incorporate by
reference AHRI 1500-2015. Therefore, for the reasons discussed here and
in the February 2022 NOPR, DOE is adopting the proposals related to
this topic made in the February 2022 NOPR.
3. ANSI Z21.47
Prior to the amendments adopted in this final rule, the CWAF test
procedure required the use of procedures contained in ANSI Z21.47-2012
that are relevant to the steady-state efficiency measurement (i.e.,
sections 1.1, 2.1 through 2.6, 2.39, and 4.2.1 of ANSI Z21.47-2012).
In the February 2022 NOPR, DOE proposed to replace the
incorporation by reference of ANSI Z21.47-2012 with ANSI Z21.47-2021.
87 FR 10726, 10734 (Feb. 25, 2022). DOE explained in the February 2022
NOPR that all of the differences it had identified between the two
versions of the standard were non-substantive and would not impact the
test method or result. Id. However, DOE also noted that ANSI Z21.47-
2012 requires burner operating characteristics tests to be conducted
with test gas G (i.e., butane-air), while ANSI Z21.47-2021 allows
testing for premix burners to be done with test gas H (i.e., propane-
air) instead of test gas G at the manufacturer's option. In the
February 2022 NOPR, DOE stated that the burner operating
characteristics tests (including which test gas is used for them) do
not affect the TE measurement of a CWAF and requested comment on
whether the option provided in section 5.4a of ANSI Z21.47-2021 to use
test gas H when performing the three burner characteristics tests would
impact the representativeness or burden of the thermal efficiency test.
Id.
Lennox, Daikin, Carrier, and AHRI stated that section 5.4a of ANSI
Z21.47-2021 is used for safety certification testing, and is unrelated
to TE, and, therefore, recommended DOE should not reference this
section. (Lennox, No. 19 at p. 3; Daikin, No. 25 at p. 2; Carrier, No.
22 at p. 2; AHRI, No. 17 at p. 2) Rheem also stated that the thermal
efficiency test is not affected by the burner operating characteristics
test. (Rheem, Public Meeting Transcript, No. 15 at p. 11) DOE received
no other comments related to its proposal to incorporate by reference
ANSI Z21.47-2021.
For the reasons discussed here and in the February 2022 NOPR, DOE
is amending the test procedure for CWAFs to replace the incorporation
by reference of ANSI Z21.47-2012 with ANSI Z21.47-2021. In addition,
DOE agrees with stakeholders that section 5.4a of ANSI Z21.47-2021 does
not impact TE, and, therefore, does not need to be referenced in the
DOE test procedure for CWAFs. As such, DOE is not including reference
to this section in the DOE test procedure.
4. ANSI/ASHRAE 103
Prior to adoption of the amendments in this final rule, DOE's test
procedure for gas-fired condensing CWAFs referenced ANSI/ASHRAE 103-
2007. In the February 2022 NOPR, DOE proposed to amend the test
procedure by removing the reference to ANSI/ASHRAE 103-2007 and to
instead reference ANSI/ASHRAE 103-2017, having determined that the only
differences between the standards in the sections utilized by the CWAF
test method were editorial in nature. 87 FR 10726, 10735. An updated
version of ANSI/ASHRAE 103, ANSI/ASHRAE 103-2022, has since been
released. DOE reviewed ANSI/ASHRAE 103-2022 and determined that, for
the sections utilized in the test methods for CWAFs, there is no
difference between the two versions of the standard.
DOE did not receive any comments in response to its proposal to
reference ANSI/ASHRAE 103-2017.
Accordingly, for the reasons explained previously and because DOE
has found there is no difference between ANSI/ASHRAE 103-2017 and ANSI/
ASHRAE 103-2022 in the sections utilized for the CWAFs test procedure,
DOE is amending the test procedures for CWAFs to incorporate by
reference ANSI/ASHRAE 103-2022.
C. Thermal Efficiency Two Metric
As previously discussed, EPCA requires that the test procedures for
CWAFs be those generally accepted industry testing procedures or rating
procedures developed or recognized by AHRI or ASHRAE, as referenced in
ASHRAE Standard 90.1. (42 U.S.C. 6314(a)(4)(A)) If such an industry
test procedure or rating procedure is amended, the Secretary shall
amend the test procedure for the product as necessary to be consistent
with the amended industry test procedure or rating procedure unless the
Secretary determines, by rule, published in the Federal Register and
supported by clear and convincing evidence, that to do so would not
meet the requirements in 42 U.S.C. 6314(a)(2) and (3) related to
representative use and test burden.\8\ (42 U.S.C. 6314(a)(4)(B))
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\8\ 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 shall 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 shall provide that such costs shall
be 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.
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In the February 2022 NOPR, DOE tentatively determined that a test
procedure that includes jacket loss and accounts for part-load
operation would better produce test results that reflect energy
efficiency, energy use, and estimated operating costs of CWAFs during a
representative average use cycle. 87 FR 10726, 10735 (Feb. 25, 2022).
Therefore, DOE proposed to account for these factors by establishing a
new test procedure and metric for CWAFs, termed TE2. DOE proposed to
establish appendix A to subpart D of 10 CFR part 431 as the test method
for calculating TE and to establish a new appendix B to subpart D of 10
CFR part 431, which would contain the new test method for TE2. The
proposed test procedure at appendix B would generally adopt the same
changes proposed for the current test procedure at appendix A but would
additionally account for jacket losses and part load operation. 87 FR
10726, 10735-10737 (Feb. 25, 2022). Additionally, DOE proposed that
manufacturers would be permitted to make voluntary representations
using TE2, and that mandatory use of the TE2 test procedure
[[Page 36224]]
would be required at such time as compliance is required with amended
energy conservation standards based on TE2, should DOE adopt such
standards. 87 FR 10726, 10737.
DOE received several comments supporting DOE's proposed test
procedure for TE2 in the February 2022 NOPR. NYSERDA generally
supported DOE's efforts to establish the TE2 metric because it will
improve representativeness of CWAF field performance. (NYSERDA, No. 16
at p. 2) The Joint Advocates supported DOE's proposal to establish the
TE2 metric, noting that the current TE metric only accounts for flue
losses, which provides little incentive to manufacturers to adopt
technologies that impact efficiency in the field, and not just TE. The
Joint Advocates, therefore, stated that the TE2 metric would better
reflect a representative average use cycle and would encourage design
changes that would reduce energy consumption. (Joint Advocates, No. 21
at p. 1)
DOE also received several comments opposing the proposed test
procedure for TE2. Lennox stated that the proposed new TE2 efficiency
metric and methodology is a significant change that would significantly
increase the test burden, with the commenter asserting that DOE has not
provided supporting data that would justify these changes. Lennox
argued that introducing such changes at the NOPR stage did not allow
stakeholders sufficient time to fully evaluate their impacts and
provide comment. Lennox noted that in standards rulemakings, DOE has
declined to adopt or propose more-stringent standards due to lack of
clear and convincing evidence that standards would be economically
justified, and the commenter asserted that in their review of current
CWAF test procedure and standards rulemakings, DOE has not provided
clear and convincing evidence to establish the TE2 metric. Therefore,
Lennox recommended that DOE should limit its test procedure amendments
to those related to TE; otherwise, if DOE continues to pursue TE2, the
commenter argued that DOE should revert back to the RFI stage so as to
allow for more stakeholder engagement regarding the proposals in the
TE2 metric. Lennox also argued against adoption of the TE2 metric
because of the associated cumulative regulatory burden. (Lennox, No. 19
at pp. 1-2) AHRI opposed adoption of the TE2 test procedure and metric
because there was no reference to such a proposal for a new metric or
any form of part-load testing in the May 2020 RFI and because DOE
failed to include key stakeholders in the development of TE2. In
addition, the commenter stated that there is not sufficient data or
justification indicating that such a change to the metric would result
in any additional energy savings. AHRI stated that the proposal to
adopt the TE2 metric is premature, and that if DOE wishes to do so, DOE
should go back to the RFI stage, conduct tests, and release data
showing the new test procedure is significantly more representative
than the current test procedure. AHRI also argued that the proposed TE2
metric is not economically justified, and that if DOE were to adopt
energy conservation standards based on such a metric, a crosswalk would
run the risk of inadvertently pushing compliant units out of the market
to produce a standard that can only be met through use of condensing
technology. Therefore, AHRI urged DOE to continue using the current TE
metric. (AHRI, No. 17 at pp. 2-3) Daikin agreed with AHRI on this
issue. (Daikin, No. 25 at p. 2) AGA and APGA stated that while they are
supportive of AHRI's comments overall, they wish to reiterate that they
do not support DOE adopting the TE2 metric because it is not clear that
it is more representative than the existing DOE test procedure, and
because there is no evidence to support that the proposed TE2 test
procedure would result in a significant change in energy savings. AGA
and APGA also expressed concern that adopting energy conservation
standards based on the TE2 metric would result in a standard that could
only be met through use of condensing technology. (AGA and APGA, No. 23
at p. 2) Carrier acknowledged that including jacket loss and part load
operation in the thermal efficiency metric would create a more
representative metric but asserted that more investigation and analysis
needs to be completed before doing so. (Carrier, No. 22 at p. 2)
In response, DOE notes that the TE metric only accounts for flue
losses as measured while the CWAF is operating at its maximum input
rate. Through testing of other similar appliances (e.g., consumer
furnaces), DOE has found that the efficiency can vary when the unit
operates at different fuel input rates; hence, test methods for such
appliances require testing at multiple fuel input rates. Therefore, DOE
concludes that including more than one fuel input rate will improve
representativeness of CWAF energy efficiency as compared to only
testing at the maximum input rate, since it will capture performance at
additional operating points. Regarding jacket losses, DOE has found
that CWAFs are often installed outside, and as a result, jacket losses
can contribute significantly to overall equipment energy use. Thus, DOE
concludes that accounting for jacket losses results in a metric that is
more representative of CWAF performance than a metric that ignores such
losses. Further, DOE notes that the methods proposed for determining
TE2, which require testing to determine jacket loss and TE, are already
in use in either industry standards (e.g., ANSI Z21.47) or DOE's own
test method for CWAFs. Therefore, manufacturers should be familiar with
the methods of testing such that reverting to an RFI would not be
necessary to provide time for additional input. While DOE recognizes
that additional testing at the minimum input rate and for jacket loss
would increase test burden, which is discussed in more detail in
section III.G, of this document, DOE has concluded that the benefit of
the increased representativeness offsets the additional test burden.
Additionally, DOE would make clear that representations using the TE2
metric are not mandatory until such time as compliance with a standard
denominated in terms of the TE2 metric is required, should DOE adopt
such a standard. In this rulemaking, DOE is not amending standards to
be based on TE2; rather, DOE is making available an optional test
method, should manufacturers wish to make representations of efficiency
using a more comprehensive metric. If, in a future energy conservation
standards rulemaking, DOE considers whether to adopt an energy
conservation standard based on the TE2 metric, DOE would further weigh
the benefits and burdens of doing so at that time, including the
potential additional energy savings that could be achieved through use
of TE2 as the regulatory metric as compared to TE and whether there is
economic justification for doing so. Based on these considerations, DOE
has determined to adopt the proposals in the February 2022 NOPR
regarding establishing TE2 and appendix B. The following sections
discuss the different components of TE2 (i.e., jacket loss and part-
load operation) and specific comments from interested parties on those
topics in more detail.
1. Jacket Loss
In the February 2022 NOPR, DOE proposed to adopt section 5.40 of
ANSI Z21.47-2021 for the purpose of measuring jacket loss for the TE2
metric. 87 FR 10726, 10737 (Feb. 25, 2022). DOE also proposed to
incorporate the jacket loss into the TE2 metric by subtracting it
(along with flue losses) from 100 percent after applying a jacket loss
factor to account for installation
[[Page 36225]]
location. DOE proposed to apply a jacket loss factor of 1.7 for CWAFs
designed for indoor installation in an unheated space (i.e., isolated
combustion system), 3.3 for CWAFs designed for outdoor installation
(including, but not limited to, CWAFs that are weatherized, or approved
for resistance to wind, rain, or snow), or 0 for CWAFs designed for
installation indoors within a heated space, which is consistent with
the values found in ANSI/ASHRAE 103-2017. Id. DOE received multiple
comments regarding the proposed jacket loss test procedure to be used
in determining TE2.
NEEA, the CA IOUs, and the CEC generally supported DOE's proposals
to include jacket loss in the TE2 metric. (NEEA, No. 24, at p. 1; CA
IOUs, No. 20, at p. 1; CEC, No. 18, at p. 2) The CA IOUs and the CEC
also specifically noted that the jacket loss factors are appropriate.
(CA IOUs, No. 20, at p. 1; CEC, No. 18, at p. 2)
Daikin, Carrier, and AHRI generally opposed DOE's proposal to
include jacket loss in the TE2 metric. (Daikin, No. 25 at p. 2; Carrier
No. 22 at pp. 2-3; AHRI No. 17 at p. 3) More specifically, Daikin
stated that the burden for conducting a jacket loss test is excessive
and is duplicative given that ASHRAE Standard 90.1 already requires a
maximum jacket loss of 0.75 percent. (Daikin, No. 25 at p. 2) Carrier
also stated that the jacket loss test, in particular the setup and data
acquisition, creates additional burden on manufacturers, and that this
increases with the size of the unit being tested. (Carrier No. 22 at
pp. 2-3) Additionally, Carrier stated that more clarity is needed on
how to properly run the test, as the industry has several methods to
conduct it. (Id.) Carrier stated that while other equipment includes
jacket loss in their calculation of efficiency (e.g., residential
furnaces and AFUE), it is hard to scale this to CWAFs. Carrier also
noted that with ASHRAE Standard 90.1 limiting jacket loss to 0.75
percent, many large CWAFs may be very close to this value.
Additionally, Carrier stated that including the 3.3 factor for
weatherized equipment creates a sizeable impact to the thermal
efficiency, and that if a future energy conservation standard for TE2
is not set correctly, it would require products to operate in a range
that condensing may occur. (Id.) AHRI stated that jacket losses are
measured on the furnace jacket, not on the rooftop unit (RTU)
jacket,\9\ and that furnace jackets are typically embedded far inside
the RTU, which requires the CUAC/HP to be taken apart in order to reach
the CWAF jacket. AHRI stated that this is an extremely burdensome task,
and that manufacturers are already required to comply with ASHRAE
Standard 90.1, which requires jacket loss to be less than 0.75 percent
(although AHRI also noted that only the worst-case models are tested).
AHRI also stated that the additional granularity of a thermal
efficiency rating that incorporates jacket loss would be negligible.
(AHRI No. 17 at p. 3 and 5) Rheem stated that jacket losses have to be
below 1.5 percent for equipment sold in Canada and below 0.75 percent
for equipment to comply with ASHRAE Standard 90.1. (Rheem, Public
Meeting Transcript, No. 15 at p. 24)
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\9\ RTUs are packaged units that can include both a commercial
unitary air conditioner (CUAC) and a CWAF and are designed for
installation on the rooftop of commercial buildings.
---------------------------------------------------------------------------
In response, DOE recognizes that performing an additional test to
determine the jacket loss of a CWAF is more burdensome than not testing
for jacket loss; however, as previously discussed, DOE has concluded
that including jacket loss in the TE2 metric will provide a more
representative measure of energy efficiency. DOE disagrees with AHRI
that jacket losses would be negligible, as the percentage loss is
included directly in the TE2 calculation. As noted by Carrier, many
CWAFs may be close to the 0.75 percent requirement. Because the jacket
loss percentage is multiplied by the jacket loss factor, for
weatherized CWAFs designed to be installed outdoors (which represent
the majority of CWAFs on the market and which have a jacket loss factor
of 3.3) a jacket loss of 0.75 percent could result in a difference in
TE2 of nearly 2.5 percent as compared to a unit with negligible jacket
losses, which DOE considers significant.
Regarding Carrier's concerns that burden increases with the size of
the unit, DOE acknowledges that additional testing burden would be
incurred if manufacturers decide to test according to TE2, and may
increase more significantly for larger units. However, DOE has
concluded that this burden would be outweighed by the anticipated
improvement in representativeness. DOE also notes that CWAFs are
eligible to use alternative efficiency determination methods (AEDMs,),
which are typically used by manufacturers to mitigate burden,
especially for testing larger commercial equipment. Further discussion
of the testing burden posed by TE2 is included in section III.G. of
this document.
Although DOE recognizes that TE2 testing would be more burdensome
as compared to TE, DOE has concluded that the TE2 test method is not
unduly burdensome. Further discussion of the cost of testing is
included in section III.G of this document. Additionally, DOE notes
that the use of TE2 is optional at this time, and this final rule does
not amend or otherwise impact the energy conservation standards for
CWAFs. If DOE should propose amended standards in the future
denominated in terms of the TE2 metric, DOE would consider concerns
regarding condensing operation at that time. Lastly, DOE agrees with
Carrier that additional clarity regarding how to conduct the test is
warranted. In particular, DOE notes that section 5.40 of ANSI Z21.47-
2021 is not specific as to what constitutes the ``jacket.'' Therefore,
DOE clarifies that it applies the term as defined by the CSA Group
standard CSA P.8-2022, ``Thermal Efficiencies of Industrial and
Commercial Gas-Fired Package Furnaces.'' CSA P.8-2022 defines the
jacket as the surfaces surrounding the heating section of the furnace.
The jacket includes all surfaces separating the heating section from
the supply air, outside air, or condenser section, including the bottom
surface separating the heating section from the basepan. DOE has
included a description of the jacket in accordance with this definition
in section 1.2 of appendix B.
2. Part-Load Performance
In the February 2022 NOPR, DOE proposed to require that, for CWAFs
with two-stage or modulating burners, the flue loss be determined at
both the maximum and minimum input rates on the nameplate of the unit
and that the jacket loss be determined at the maximum input rate and
optionally at the minimum input rate. If the jacket loss were
determined only at the maximum input rate, DOE proposed to assign an
equivalent value at the minimum input rate. DOE proposed that TE2 would
then be calculated as the average of the efficiencies determined at
both the maximum and minimum input rates using the flue loss and jacket
loss determined at each input rate, which reflects an average use case
of 50 percent of the time operating at full load and 50 percent of the
time operating at part-load. 87 FR 10726, 10738 (Feb. 25, 2022).
In response to the February 2022 NOPR, AHRI stated that unlike for
air-conditioning equipment, the range in variability in performance
between part-load and full-load is small and that adding part-load
performance into the
[[Page 36226]]
measurement of CWAF performance would not add to market clarity,
especially given the burden of retesting all CWAFs on the market to
assess performance according to such a test procedure. (AHRI, No. 17 at
pp. 3-4)
DOE also received comments from several stakeholders supporting the
inclusion of part-load performance in TE2. Specifically, NEEA supported
the inclusion of part-load operation in the proposed TE2 metric and
noted that they have observed cases where CWAFs have had reduced
efficiency at part-load when compared to full-load. Therefore, NEEA
concluded that including part-load efficiency in TE2 will create a more
representative efficiency metric. (NEEA, No. 24 at p. 6) The CA IOUs
supported DOE's efforts to incorporate part-load operation within the
TE2 metric and agreed with DOEs assertion in the February 2022 NOPR
that most CWAFs have two or more stages of heating, that CWAFs spend a
substantial time operating in part-load, and that including part-load
performance in a TE2 metric would increase representativeness. (CA
IOUs, No. 20 at pp. 1-2) The CEC supported including part-load
performance in the TE2 metric and noted that CWAFs spend a large
percentage of time in part-load operation. (CEC, No. 18 at p. 2)
Carrier stated that part-load performance should be part of the CWAF
test procedure. (Carrier, No. 22 at pp. 3-4)
As discussed previously, DOE has observed during testing of similar
products that efficiency can differ at full load as compared to part
load and has concluded that adding testing during part-load operation
would improve representativeness as compared to a test method that only
requires operation at the maximum input. Therefore, DOE is adopting
part-load testing in the TE2 metric, as initially proposed in the
February 2022 NOPR. Regarding the need to re-test CWAFs currently rated
to the TE metric, DOE notes that testing to determine TE2 would not be
required until the compliance date of any energy conservation standards
based on that metric. However, DOE concludes that the improved
representativeness of the TE2 metric would outweigh the additional test
burden.
DOE also received several comments regarding the proposal to weight
both full-load and part-load operation at 50 percent when calculating
TE2.
The CA IOUs encouraged DOE to continue to evaluate what full-load
and part-load weighting factors would improve representativeness of an
average use cycle; however, the CA IOUs stated that they do not oppose
DOE's proposal to use 50 percent weighting factors, given the lack of
national data on such full-load and part-load performance. (CA IOUs,
No. 20 at p. 2) The CEC supported the DOE's proposal to equally weight
full-load and part-load operation, but also stated that DOE should
continue to evaluate the average use cycle of CWAFs. (CEC, No. 18 at p.
2)
NEEA recommended DOE reconsider the proposed weighting of low and
high fire in the TE2 metric. NEEA presented a figure showing the
modeled proportion of time at high fire and low fire for three
locations in Canada (Winnipeg, Montreal, and Toronto) and two building
types (retail and warehouse). The commenter stated that modeling has
shown that, in colder North American climate zones (5A, 6A, and 7), the
ratio of high fire to low fire is only close to 50/50 for warehouses in
these cold climates, but for other use types, the ratio was closer to
30 percent at low fire and 70 percent at high fire. NEEA stated that
because the U.S. generally has warmer climate zones than Canada, NEEA
would expect increased part-load operation in the U.S., and, therefore,
it argued that a 50/50 weighting would not be representative of CWAFs
in the U.S. (NEEA, No. 24 at pp. 6-7)
The Joint Advocates encouraged DOE to further consider alternative
weighting factors for full-load and part-load operation that they argue
may be more representative of average use. The Joint Advocates also
noted that the February 2022 NOPR refers to an estimate from NEEA that
CWAFs spend about 10 to 20 percent of their time operating at full
load, but that DOE did not use that estimate because the Department
tentatively determined that the climate regions from which the estimate
was derived were not representative of the U.S. The Joint Advocates
urged DOE to reconsider the NEEA estimate because they understand that
while total operating hours will vary significantly based on climate
region, the percentage of time spent at full load is relatively
constant across climate regions. (Joint Advocates, No. 21 at p. 2)
Rheem stated that it is not appropriate to average the maximum and
minimum thermal efficiencies and noted that in ANSI/ASHRAE 103 (i.e.,
the ASHRAE test method for consumer furnaces) there is a method for
determining the weightings, and the unit does not run at the maximum
input very often. Rheem suggested that the minimum input rate should be
weighted more than the maximum input rate. (Rheem, Public Meeting
Transcript, No. 15 at pp. 27-28) Daikin also stated that 50 percent
weighting factors for full-load and part-load performance are not
appropriate. Further, Daikin stated that the approach to weighting
full-load and part-load operation in ANSI/ASHRAE 103 cannot be used for
CWAFs because it was generated for residential products and the
operational profile of commercial products is radically different.
(Daikin, No. 25 at p. 2) Carrier commented that time spent at part-load
is much longer than full-load, and, therefore, DOE's proposed 50
percent weighting factor is not appropriate. Carrier recommended that
more investigation and analysis should be performed to determine
appropriate weighting factors that account for all types of furnaces
(i.e., two-stage, multi-stage, and modulating). (Carrier, No. 22 at pp.
3-4) AHRI also stated that the 50 percent weighting factors proposed by
DOE in the February 2022 NOPR are not representative. (AHRI, No. 17 at
p. 4)
In response, DOE notes that the modeling presented by NEEA shows
that in the three regions in Canada, the percentage of time a CWAF
could operate at high fire versus low fire varied greatly, with CWAFs
in some applications operating as little as approximately 25 percent of
time in high fire (and 75 percent in low fire), while CWAFs in other
applications were modeled to operate more than 70 percent of time in
high fire (and 30 percent in low fire). Warehouses in all three
locations were modeled to operate in high fire over 50 percent of the
time, while retail buildings in all three locations were modeled to
operate in high fire less than 50 percent of the time. Although NEEA
claimed that the warmer climate in the U.S. would result in less time
operating at full load, that is not necessarily the case as CWAFs in
the U.S. would likely be sized differently from those in Canada due to
the reduced heating loads. As noted by the Joint Advocates, while total
operating hours will vary significantly based on climate region, the
percentage of time spent at full load could remain relatively constant
across climate regions. Although several commenters asserted that
weighting equally at 50 percent in full-load and in part-load is not
representative, no other commenters presented alternative data, nor is
DOE aware of any data that would be useful to better characterize the
appropriate weighting factors. Therefore, in this final rule, DOE is
adopting a calculation method that weights full-load and part-load
operation equally. Should DOE become aware of any new data regarding
time spent operating at each input rate or data specific to different
furnace types in the future, DOE could consider
[[Page 36227]]
revising the calculation accordingly in a subsequent rulemaking.
D. Electrical Energy Consumption
In the February 2022 NOPR, DOE tentatively determined not to
account for electrical energy consumption of CWAF auxiliary power
components (e.g., controls and/or combustion blowers/fans) or the
supply air fan in the CWAF test procedure. 87 FR 10726, 10739 (Feb. 25,
2022). Specifically, regarding supply fan energy consumption, DOE noted
that CWAFs are typically installed within the same cabinet as a CUAC
and that this energy is generally accounted for in the current CUAC
test procedure, although furnace-only operation hours are not included.
As such, DOE tentatively determined that energy consumption during
furnace-only operation hours would be better addressed in a future
amendment to the CUAC test procedure. Id. Regarding auxiliary power
consumption, DOE tentatively determined that including such power
consumption into a CWAF performance metric would have a negligible
impact on the measured energy efficiency of a CWAF. Id.
In response to the February 2022 NOPR, NYSERDA encouraged DOE to
measure fan energy consumption during furnace-only operation in the
CWAF test procedure. (NYSERDA, No. 16 at p. 2) NEEA also recommended
that DOE account for electricity consumption used in a CUAC, including
fan and auxiliary energy use, that relates to CWAF energy consumption.
In relation to DOE's tentative determination in the February 2022 NOPR
that such energy consumption would be better addressed in a future
amendment to the CUAC test procedure, NEEA stated such an approach
would likely leave out the portion of the hours during the year where
fan energy is consumed when only the CWAF is operating. NEEA stated
that it understands DOE's desire for fan energy to ``be captured in a
single test procedure,'' but the commenter argued that this goal is not
achievable when cooling and heating efficiencies are regulated
separately and also not achievable in a market as diverse as that for
commercial HVAC. Additionally, NEEA mentioned that because fan and
other auxiliary electrical end uses are integral to the function of any
CWAF, it is critical than any CWAF TP and performance metric account
for them. (NEEA, No. 24 at p. 4)
After carefully considering these comments, DOE maintains its
position presented in February 2022 NOPR that, at present, integrating
the auxiliary electrical energy consumption into the efficiency metric
for CWAF would result in negligible impact. Further, DOE also maintains
that the fan efficiency is better accounted for in a single test method
that addresses all fan energy consumption. Accordingly, DOE is
proposing to address the supply air fan energy use for CWAFs, including
during operation in heating-only mode, in the ongoing CUACs test
procedure rulemaking. Therefore, DOE is not adopting measures of
auxiliary electrical energy use or the electrical energy use of the
supply air fan in this final rule.
E. Other Test Procedure Updates and Clarifications
In the February 2022 NOPR, DOE used the terms ``vent hoods,''
``vent pipes,'' and ``flue outlets'' to describe the section of a CWAF
that carries the flue gas away from the unit. DOE received a comment
from AAON recommending DOE use the term ``flue outlets,'' because it is
the most accurate way to describe those components. (AAON, No. 14 at p.
1) In response, DOE has determined it appropriate to use only the term
``flue outlet(s)'' in order to prevent confusion associated with using
multiple terms to refer to the same outlet. As such, DOE will use the
term ``flue outlet(s)'' in this final rule, as well as in appendix A
and appendix B.
1. Flue Temperature Measurement in Models With Multiple Flue Outlets
In the February 2022 NOPR, DOE proposed to add instructions to
clarify the test method for models with multiple flue outlets. 87 FR
10726, 10740 (Feb. 25, 2022). DOE proposed that measurements used to
calculate TE (e.g., flue gas temperature, CO2 in flue
gasses), be made separately for each flue outlet, and that they are
weighted proportionally to the size of each flue outlet when
calculating flue loss. Further, DOE proposed that test requirements,
such as determining when equilibrium conditions occur based on the flue
gas temperature, are determined based these weighted measurements. DOE
noted that this proposal is predicated on the assumption that the
amount (i.e., mass flow) of flue exhaust exiting each flue outlet is
proportional to the outlet size. DOE recognized that ``size'' of the
flue outlet may be measured in various ways, and, therefore, the
Department proposed to specify that flue outlet size would be
determined by calculating the outlet face area. DOE sought comments on
these proposals. Id.
Lennox stated that the size of the flue outlet may not be
representative of the amount of flue exhaust passing through the flue
outlet, and that DOE should consider relying on the supplemental
testing instructions or review the input capacity for each heating
section as the weighted average instead of the cross-sectional area of
the flue outlet. (Lennox, No. 19 at p. 3) AHRI and Carrier supported
clarifying how to test units with multiple flue outlets but recommended
that the measurement and performance rating for each flue outlet should
be based on input rating of each furnace module instead of the size of
the flue outlet. (AHRI, No. 17 at p. 4; Carrier, No. 22 at p. 4)
Based on these comments DOE understands that the flue outlet size
may not directly correspond to the mass flow of flue gases exiting from
that outlet. Consequently, DOE agrees that the fuel input rating for
each furnace module would be a better indicator of the flue gases
exiting the outlet for that specific module. Therefore, DOE amends the
test procedure to clarify that for units with multiple flue gas
outlets, the measurements used to calculate TE (e.g., flue gas
temperature, CO2 in flue gasses) are to be made separately
for each flue outlet, and are to be weighted proportionally to the
input capacity associated with the furnace module.
2. Flue Temperature Measurement in Models With Vent Space Limitations
In the February 2022 NOPR, DOE noted that section 5.16 of ANSI
Z21.47-2021 specifies measuring the flue gas temperature using nine
individual thermocouples placed in specific locations; however, these
sections do not provide guidance on how to measure the flue gas
temperature if the vent size constrains the space where the
thermocouples are to be placed to the point that normal operation of
the unit is inhibited when nine thermocouples are installed. 87 FR
10726, 10740 (Feb. 25, 2022). DOE proposed to specify in the DOE test
procedure that when testing gas-fired and oil-fired CWAFs, the flue gas
temperatures shall be measured using nine individual thermocouples when
the flue outlet is larger than 2 inches in diameter and may optionally
be measured using five individual thermocouples when the flue outlet is
2 inches or smaller in diameter, which DOE noted aligns with the
approach in ANSI/ASHRAE 103-2017. Id. at 87 FR 10741.
AAON stated that flue outlet geometry in CWAFs can vary in shape
and that the diagram referenced in ANSI/ASHRAE 103 only accounts for a
circular geometry. Consequently, AAON recommended that the number
thermocouples needed for testing should be determined by the cross-
[[Page 36228]]
sectional area of the flue outlet. (AAON, No. 14 at p. 1) Similarly,
Lennox noted that not all flue outlets are round, and, therefore, the
commenter suggested that the number of thermocouples used during the
test should be determined using the face area of the flue outlet.
(Lennox, No. 19 at p. 3) Carrier agreed that fewer thermocouples should
be used for units with smaller flue outlets, but also recommended the
determination be based on cross-sectional face area, not diameter,
since flue outlets are not always circular. (Carrier, No. 22 at p. 4)
AHRI supported DOE's proposal that the number of thermocouples used be
dependent on the flue outlet size; however, similar to other
commenters, AHRI recommend that DOE base the determination of how many
thermocouples to use on the cross-sectional area of the outlet, rather
than the diameter. AHRI also further recommended DOE review and align
its provisions with the requirement outlined in Figure 10 of AHRI 103.
(AHRI, No. 17 at p. 4)
DOE agrees that the determination of the number of thermocouples
used in the flue outlet should be based on the area of the flue outlet,
rather than diameter, because some flue outlets may not be circular.
Therefore, DOE is adopting a modification to its February 2022 proposal
so that the optional allowance to use 5 thermocouples rather than 9 in
models with flue outlets that are 2 inches or less in diameter applies
based on the cross-sectional area of the flue outlet. For a circular
flue with a diameter of 2 inches, the area would be 3.14 square inches;
thus, DOE is amending the test procedure to allow optional use of 5
thermocouples when testing models with a flue outlet that has a cross
sectional area of 3.14 square inches or less.
3. Flue Loss Determination
Section 2.39 of ANSI Z21.47-2012 and section 5.40 of ANSI Z21.47-
2021 reference Annex I for the determination of flue loss that is used
in the TE calculation. Annex I includes two methods for determining
flue loss--one method that uses a calculation, and one method that uses
nomographs shown in Figures I.1 and I.2 of ANSI Z21.47-2021. The
nomograph method may only be used when the heating value, specific
gravity, and flue gas CO2 of a CWAF fall within a specified
range.\10\ If these conditions are met, either calculation method may
be used. In the February 2022 NOPR, DOE proposed to require that the
calculation method must be used when determining flue loss because the
nomograph method is not applicable for all tests, and the calculation
method is likely to provide better repeatability by eliminating
subjective differences in interpreting the nomograph. 87 FR 10726,
10741 (Feb. 25, 2022).
---------------------------------------------------------------------------
\10\ Heating value for natural gas or propane must be 970-1100
Btu/ft\3\ or 2466-2542 Btu/ft\3\, respectively. Specific gravity for
natural gas or propane must be 0.57-0.70 or 1.522-15.74,
respectively. Ultimate carbon dioxide for natural gas or propane
must be 11.7-12.2% or 13.73-13.82%, respectively.
---------------------------------------------------------------------------
DOE received comments from Daikin, Carrier, Lennox, Rheem, and AHRI
that supported this proposal, and received no other comments on this
topic. (Daikin, No. 25 at p. 3; Lennox, No. 19 at p. 3; Carrier, No. 22
at p. 5; Rheem, Public Meeting Transcript, No. 15 at p. 21; AHRI, No.
17 at p. 4) Based on the previously discussed rationale, DOE has
determined that requiring the calculation method will help improve test
repeatability. As such, DOE is requiring that the calculation method,
not the nomograph method, from Annex I in ANSI Z21.47-2021 be used for
the determination of flue loss.
4. General Approach
In response to the February 2022 NOPR, DOE received several
comments regarding its general approach to the test method for CWAFs.
AGA and APGA recommend DOE consider implementing the
recommendations for the recent National Academies of Sciences
Engineering and Medicine (NASEM) on appliance standards rulemakings,
whether for test procedures or energy conservation standards. (AGA and
APGA, No. 23 at pp. 2-3)
Given that this is a test procedure rulemaking for which DOE must
meet specific statutory criteria as outlined in 42 U.S.C. 6314, the
recommendations in the NASEM report, which pertain specifically to the
processes by which DOE analyzes energy conservation standards, are not
applicable. DOE will consider this comment in a separate rulemaking
considering all covered product and covered equipment categories.
DOE also received comments from the Joint Advocates and NEEA
recommending that DOE consider a ``whole box'' approach for measuring
the performance of CWAFs, similar to the approach found in CSA P.8-
2022, ``Thermal Efficiencies of Industrial and Commercial Gas-fired
Package Furnaces.'' \11\ (Joint Advocates, No. 21 at pp. 1-2, NEEA, No.
24 at pp. 1-5) More specifically, the Joint Advocates and NEEA stated
that while they supported DOE's efforts to establish TE2, they
encouraged DOE to evaluate the potential use of CSA P.8-2022. They
asserted that CSA P.8 would more accurately represent overall
efficiency of a CWAF because the new heating metric in that standard
(i.e., ``total heating season coefficient of performance'') calculates
the efficiency of a CWAF using a more holistic approach, by
incorporating factors such as burner efficiency, total enclosure heat
losses, fan energy consumption, and heat gains from heat recovery. Id.
Similarly, NYSERDA also encouraged DOE to consider any forthcoming
updates that may better measure the holistic energy use of CWAFs.
(NYSERDA, No. 16 at p. 2)
---------------------------------------------------------------------------
\11\ CSA P.8-2022 is available for purchase at:
www.csagroup.org/store/product/CSA%20P.8:22/. (Last accessed Jan.
31, 2023).
---------------------------------------------------------------------------
As discussed in section I.A of this document, EPCA requires that
the test procedures for CWAFs be those generally accepted industry
testing procedures or rating procedures developed or recognized by AHRI
or ASHRAE, as referenced in ASHRAE Standard 90.1. (42 U.S.C.
6314(a)(4)(A)) If such an industry test procedure or rating procedure
is amended, the Secretary shall amend the test procedure for the
product as necessary to be consistent with the amended industry test
procedure or rating procedure unless the Secretary determines, by rule,
published in the Federal Register and supported by clear and convincing
evidence, that to do so would not meet the requirements in 42 U.S.C.
6314(a)(2) and (3) related to representative use and test burden. (42
U.S.C. 6314(a)(4)(B)) In this case, the industry test standards
referenced by ASHRAE Standard 90.1 are ANSI Z21.47 for gas-fired CWAFs
and UL 727 for oil-fired CWAFs. The test methods adopted in this final
rule incorporate by reference those industry standards, and are
generally consistent with and build upon those industry standards by
providing clarifications or other modifications, as necessary, to meet
the requirements of EPCA. DOE has determined that the test procedures
for CWAFs adopted in this final rule will produce test results which
reflect energy efficiency of CWAFs during a representative average use
cycle, are not unduly burdensome to conduct, as required by EPCA.
Further, DOE notes that the scope of CSA P.8-2022 indicates that the
standard is intended to provide ``cold climate'' performance criteria
that is representative of use in colder climates found in Canada and
other northern locations, which may not be representative of the U.S.
as a whole.
[[Page 36229]]
Therefore, DOE did not find it necessary to move to a test method that
uses the approach taken by CSA P.8-2022. In response to NYSERDA, DOE
will continue to monitor future applicable industry test standard
updates related to CWAFs.
F. Effective and Compliance Dates
The effective date for the adopted CWAFs test procedure amendments
is 30 days after the date of publication of this final rule in the
Federal Register.
Regarding the compliance date, EPCA prescribes that all
representations of energy efficiency and energy use, including those
made on marketing materials and product labels, must be made in
accordance with an amended test procedure for CWAFs, beginning 360 days
after the date of publication of this final rule in the Federal
Register. (42 U.S.C. 6314(d)(1))
To the extent the modified test procedure adopted in this final
rule is required only for the evaluation under updated CWAF energy
conservation standards (i.e., standards denominated in terms of the new
TE2 metric), compliance with the amended test procedure does not
require use of such modified test procedure provisions until the
compliance date of such updated standards, if adopted.
G. Test Procedure Costs
EPCA requires that the test procedures for CWAFs be those generally
accepted industry testing procedures or rating procedures developed or
recognized by either AHRI or ASHRAE, as referenced in ASHRAE Standard
90.1. (42 U.S.C. 6314(a)(4)(A)) Further, if such an industry test
procedure is amended, DOE must amend its test procedure to be
consistent with the amended industry test procedure unless DOE
determines, by rule published in the Federal Register and supported by
clear and convincing evidence, that such an amended test procedure
would not meet the requirements in 42 U.S.C. 6314(a)(2)-(3) related to
representative use and test burden. (42 U.S.C. 6314(a)(4)(B))
In this final rule, DOE is amending the test procedure for CWAFs
for determining TE by incorporating by reference the most up-to-date
versions of the industry test standards referenced in the DOE test
procedure, and by providing additional detail for the test setup for
models with multiple flue outlets and models with flue outlets having
space limitations. DOE has determined that these amendments to the test
procedure for determining TE would not be unduly burdensome for
manufacturers to conduct, and that the test procedures for this
equipment are consistent with the industry test procedure updates. DOE
has also determined that the amendments to the test procedure for
determining TE would improve the representativeness, accuracy, and
reproducibility of the test results and would not be unduly burdensome
to conduct. DOE expects that the test procedure in appendix A for
determining TE will not increase testing costs.
DOE is also establishing a new metric for CWAFs, TE2, and a new
appendix B, which includes the test procedure for determining TE2. In
the February 2022 NOPR, DOE estimated that the additional test cost due
to the additional part-load test and jacket loss test required for the
TE2 metric would be $2,200, compared to the DOE test procedure using
the TE metric, which DOE estimated to be $4,200 at a third-party
laboratory (i.e., a total estimated cost of $6,400 per tested unit for
the amended TE2 test procedure). Therefore, assuming two units are
tested per basic model,\12\ DOE estimated the testing cost associated
with the newly proposed appendix B test procedure to be $12,800 per
basic model. 87 FR 10726, 10741-10742 (Feb. 25, 2022). DOE also noted
that in accordance with 10 CFR 429.41, CWAF manufacturers may elect to
use an AEDM to rate models for the TE2 metric, which significantly
reduces testing costs to industry. DOE estimated the per-manufacturer
cost to develop and validate an AEDM to determine TE2 for CWAF
equipment to be $17,300. DOE estimated a cost of $46 per basic model
for determining energy efficiency using a validated AEDM.\13\ 87 FR
10726, 10742 (Feb. 25, 2022). Additionally, DOE has determined that the
appendix B test procedure and TE2 calculation would alter the measured
energy efficiency of a CWAF.
---------------------------------------------------------------------------
\12\ Per the sampling requirements specified at 10 CFR
429.11(b), manufacturers are required to test at least two units to
determine the rating for a basic model, except if only one unit of
the basic model is produced.
\13\ DOE's estimated initial cost to develop and validate an
AEDM includes (1) 80 hours to develop the AEDM based on existing
simulation tools; (2) an additional 16 hours to validate the AEDM
for two basic models at the cost of an engineering calibration
technician wage of $46 per hour; and (3) the cost of third-party
testing of two units per validation class (as required in 10 CFR
429.70(c)(2)(iv)). DOE estimated the additional per basic model cost
to determine efficiency using an AEDM assuming 1 hour per basic
model at the cost of an engineering calibration technician wage of
$46 per hour.
---------------------------------------------------------------------------
DOE received multiple comments on the test cost and burden
associated with performing the TE2 test procedure. Rheem generally
stated that measuring jacket loss is very labor-intensive due to the
need to take apart the unit and presents a burden to manufacturers.
(Rheem, Public Meeting Transcript, No. 15 at pp. 23-24) AHRI asserted
that there are external costs associated with this proposed test
procedure change that DOE has not accounted for, including bandwidth
limitations at laboratory facilities that would cause manufacturers to
test internally and which could delay testing of new units while
existing models are retested. (AHRI, No. 17 at p. 5) AHRI also asserted
that DOE did not accurately account for the cost of performing a jacket
loss test at full-load and part-load because determining compliance
with ASHRAE Standard 90.1 requires that only the worst-case unit in a
product line needs to be tested, but TE2 would require manufacturers to
run the jacket loss test twice every time a unit is tested. AHRI also
stated that there are no AEDMs currently available for TE2 and
developing an AEDM is extremely costly due to the number of variables
that need to be accounted for and modeled accurately (e.g., fan
capacity, cabinet geometry, variation in size of the heater, and the
inclusion of dampers, energy recovery ventilators (ERVs), and heat
recovery ventilators (HRVs) in the airflow path). AHRI also disagreed
with the Department's estimate that the associated rerating costs would
be approximately $17,400, because manufacturers will need to validate
any new AEDM by testing at least two (2) basic models, which will have
associated manufacturing and test costs. Instead, AHRI estimated that
the cost of the test samples alone will reach upwards of $30,000
(without accounting for the AEDM development cost or test time), and
that the test time must include a minimum of several days to set up for
each sample, with laboratory time being very expensive. (Id.) Daikin
supported AHRI's comments on this topic and added that testing cost and
burden will increase substantially if manufacturers must assess part-
load conditions and jacket loss. Daikin noted that if ambient
conditions must be controlled in psychometric rooms to conduct jacket
loss testing, it could impact availability of those test rooms for
other equipment such as commercial unitary air conditioners and heat
pumps. (Daikin, No. 25 at p. 3) Carrier stated that DOE underestimated
the cost to validate an AEDM, because CWAF sizes vary between 225,000
Btu/h and 2,000,000 Btu/h (which can lead to an extremely large
variation in cost). Carrier stated that to create an accurate
[[Page 36230]]
AEDM, a manufacturer would need to consider a ``worst case'' model, and
that this can cost upwards of $50,000. (Carrier, No. 22 at p. 5)
In response, DOE notes that the estimated cost of testing for TE2
presented in the February 2022 NOPR is based on actual price quotations
from third-party laboratories. Additionally, the estimated cost to
develop an AEDM reflects 80 hours to develop the AEDM based on existing
simulation tools, plus an additional 16 hours to validate the AEDM at a
rate of $46 per hour, plus the cost to conduct the test on two units as
required by 10 CFR 429.70(c)(2)(iv). DOE recognizes that depending on
each individual manufacturer's approach to testing and rating their
models (whether based on actual testing, AEDMs, or a combination of
approaches) and the number of models they would need to rate with TE2,
test costs could vary significantly. DOE's estimates are intended to
represent the typical or most likely costs given the various pathways
available for rating TE2. However, DOE recognizes that the costs could
be higher. Although TE2 testing will be cost more than the current TE
test method due to the need to perform jacket loss testing and testing
at the minimum input capacity, DOE has concluded that the additional
costs are not unduly burdensome and are justified due to the improved
representativeness of TE2 as compared to TE. Further, because there is
no requirement to make representations with TE2 at this time, DOE does
not view laboratory bandwidth limitations as a significant issue.
However, if DOE were to transition to standards based on the TE2 metric
in the future, which would require manufacturers to make
representations of TE2, DOE notes that it would provide a lead time
before compliance is required, consistent with the requirements of
EPCA,\14\ which should alleviate any laboratory bandwidth issues.
---------------------------------------------------------------------------
\14\ Under 42 U.S.C. 6313(a)(6)(C)(iv), if DOE amends standards
pursuant to a six-year-lookback review initiated under 42 U.S.C.
6313(a)(6)(C)(i), amended standards apply a minimum of three years
after publication of the amended standards. Under 42 U.S.C.
6313(a)(6)(D)(i), if DOE amends standards pursuant to an amendment
to ASHRAE Standard 90.1 levels, amended standards apply a minimum of
2 years after the effective date of the minimum energy efficiency
requirement in the amended ASHRAE Standard 90.1.
---------------------------------------------------------------------------
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 12866, 13563, and 14094
Executive Order (E.O.) 12866, ``Regulatory Planning and Review,''
58 FR 51735 (Oct. 4, 1993), as supplemented and reaffirmed by E.O.
13563, ``Improving Regulation and Regulatory Review,'' 76 FR 3821 (Jan.
21, 2011) and amended by E.O. 14094, ``Modernizing Regulatory Review,''
88 FR 21879 (April 11, 2023), requires agencies, to the extent
permitted by law, to: (1) propose or adopt a regulation only upon a
reasoned determination that its benefits justify its costs (recognizing
that some benefits and costs are difficult to quantify); (2) tailor
regulations to impose the least burden on society, consistent with
obtaining regulatory objectives, taking into account, among other
things, and to the extent practicable, the costs of cumulative
regulations; (3) select, in choosing among alternative regulatory
approaches, those approaches that maximize net benefits (including
potential economic, environmental, public health and safety, and other
advantages; distributive impacts; and equity); (4) to the extent
feasible, specify performance objectives, rather than specifying the
behavior or manner of compliance that regulated entities must adopt;
and (5) identify and assess available alternatives to direct
regulation, including providing economic incentives to encourage the
desired behavior, such as user fees or marketable permits, or providing
information upon which choices can be made by the public. DOE
emphasizes as well that E.O. 13563 requires agencies to use the best
available techniques to quantify anticipated present and future
benefits and costs as accurately as possible. In its guidance, the
Office of Information and Regulatory Affairs (OIRA) in the Office of
Management and Budget (OMB) has emphasized that such techniques may
include identifying changing future compliance costs that might result
from technological innovation or anticipated behavioral changes. For
the reasons stated in the preamble, this final regulatory action is
consistent with these principles.
Section 6(a) of E.O. 12866 also requires agencies to submit
``significant regulatory actions'' to OIRA for review. OIRA has
determined that this final regulatory action does not constitute a
``significant regulatory action'' under section 3(f) of E.O. 12866.
Accordingly, this action was not submitted to OIRA for review under
E.O. 12866.
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires
preparation of a final regulatory flexibility analysis (FRFA) for any
final rule where the agency was first required by law to publish a
proposed rule for public comment, unless the agency certifies that the
rule, if promulgated, will not have a significant economic impact on a
substantial number of small entities. As required by Executive Order
13272, ``Proper Consideration of Small Entities in Agency Rulemaking,''
67 FR 53461 (August 16, 2002), DOE published procedures and policies on
February 19, 2003, to ensure that the potential impacts of its rules on
small entities are properly considered during the DOE rulemaking
process. 68 FR 7990. DOE has made its procedures and policies available
on the Office of the General Counsel's website: www.energy.gov/gc/office-general-counsel. DOE reviewed this final rule under the
provisions of the Regulatory Flexibility Act and the procedures and
policies published on February 19, 2003.
On February 25, 2022, DOE published in the Federal Register a
notice of proposed rulemaking (February 2022 NOPR) proposing to update
the references in the Federal test procedure to the most recent version
of the relevant industry test procedures as they relate to CWAFs, as
well as to adopt a new TE2 metric. Specifically, DOE proposed to adopt
two appendices to 10 CFR 431.76--appendix A for determining TE and
appendix B for determining TE2. The TE test method in appendix A is
similar to the current method for TE, with several clarifications and
updates to incorporate by reference the most recent versions of
appliable industry test standards. The TE2 test method in appendix B
builds upon the TE test method in appendix A, but also accounts for
jacket losses and operation at the minimum input rating.
As part of the February 2022 NOPR, DOE conducted its initial
regulatory flexibility analysis (IRFA). 87 FR 10726, 10742-10744 (Feb.
25, 2022). DOE used the Small Business Administration (SBA) small
business size standards to determine whether manufacturers qualify as
small businesses, which are listed by North American Industry
Classification System (NAICS).\15\ The SBA considers a business entity
to be a small business, if, together with its affiliates, it employs
less than a threshold number of workers specified in 13 CFR part 121.
CWAF manufacturers are classified under NAICS code 333415, ``Air-
Conditioning and Warm Air Heating Equipment and Commercial and
Industrial Refrigeration Equipment Manufacturing.'' In 13 CFR
[[Page 36231]]
121.201, the SBA sets a threshold of 1,250 employees or fewer for an
entity to be considered as a small business for this category.
---------------------------------------------------------------------------
\15\ The size standards are listed by NAICS code and industry
description and are available at: www.sba.gov/document/support-table-size-standards (Last accessed Feb. 8, 2022).
---------------------------------------------------------------------------
DOE relied on publicly-available databases to identify potential
small businesses that manufacture equipment covered by this rulemaking.
DOE utilized the California Energy Commission's Modernized Appliance
Efficiency Database System (MAEDbS) \16\ and DOE's Certification
Compliance Database (CCD) \17\ to identify potential small businesses
that manufacture CWAFs covered by this rulemaking. DOE identified eight
original equipment manufacturers (OEMs) of CWAFs affected by this
rulemaking. DOE screened out companies that do not meet the definition
of a ``small business'' or are foreign-owned and operated. DOE
identified one small, domestic OEM for consideration. DOE used
subscription-based business information tools (e.g., Dun & Bradstreet
reports \18\) to determine headcount and revenue of the small business.
---------------------------------------------------------------------------
\16\ MAEDbS can be accessed at cacertappliances.energy.ca.gov/Pages/ApplianceSearch.aspx (Last accessed Feb. 8, 2022).
\17\ Certified equipment in the CCD is listed by product class
and can be accessed at www.regulations.doe.gov/certification-data/#q=Product_Group_s%3A* (Last accessed July 15, 2021).
\18\ The Dun & Bradstreet Hoovers subscription login is
accessible online at app.dnbhoovers.com/ (Last accessed Feb. 8,
2023).
---------------------------------------------------------------------------
In the February 2022 NOPR, DOE determined the one small
manufacturer had average annual revenues of approximately $3.3 million.
Additionally, DOE identified four basic models from the small
manufacturer. DOE estimated the re-rating costs for the manufacturer to
be approximately $17,400 when making use of AEDMs. The cost for this
small manufacturer to re-rate all basic models was estimated to be less
than 1 percent of annual revenue. DOE also estimated the re-rating cost
for the small manufacturer based on physical testing of all four models
based on third-party laboratory testing. Relying on pricing quotes from
third-party laboratories, DOE estimated costs of approximately $51,200
for the small business. The cost for this small manufacturer to re-rate
all basic models with physical testing was estimated to be less than
1.6 percent of annual revenue. 87 FR 10726, 10744 (Feb. 25, 2022).
DOE did not receive any comments on the number of small entities in
response to the February 2022 NOPR. As discussed in section III.G of
this document, DOE received several comments that suggested that the
February 2022 NOPR underestimated the cost of testing for TE2
generally. However, as discussed previously, the estimated cost of
testing for TE2 presented in the February 2022 NOPR is based on actual
price quotations from third-party laboratories. Additionally, the
estimated cost to develop an AEDM reflects 80 hours to develop the AEDM
based on existing simulation tools, plus an additional 16 hours to
validate the AEDM at a rate of $46 per hour, plus the cost to conduct
the test on two units as required by 10 CFR 429.70(c)(2)(iv). Although
DOE recognizes that each individual manufacturer's approach to testing
and rating their models (whether based on actual testing, AEDMs, or a
combination of approaches) could cause test costs to vary
significantly, DOE's estimates are intended to represent the typical or
most likely costs given the various pathways available for rating TE2,
and, therefore, DOE maintained its estimates from the February 2022
NOPR for this final rule.
On the basis of the de minimis compliance burden, DOE concludes and
certifies that the cost effects accruing from this test procedure final
rule would not have a ``significant economic impact on a substantial
number of small entities,'' and that the preparation of a FRFA is not
warranted. DOE will transmit a certification and supporting statement
of factual basis to the Chief Counsel for Advocacy of the Small
Business Administration for review under 5 U.S.C. 605(b).
C. Review Under the Paperwork Reduction Act of 1995
Manufacturers of CWAFs must certify to DOE that their products
comply with any applicable energy conservation standards. To certify
compliance, manufacturers must first obtain test data for their
products according to the DOE test procedures, including any amendments
adopted for those test procedures. DOE has established regulations for
the certification and recordkeeping requirements for all covered
consumer products and commercial equipment, including CWAFs. (See
generally 10 CFR part 429.) The collection-of-information requirement
for the certification and recordkeeping is subject to review and
approval by OMB under the Paperwork Reduction Act (PRA). This
requirement has been approved by OMB under OMB control number 1910-
1400. Public reporting burden for the certification is estimated to
average 35 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.
DOE is not amending the certification or reporting requirements for
CWAFs in this final rule. Instead, DOE may consider proposals to amend
the certification requirements and reporting for CWAFs under a separate
rulemaking regarding appliance and equipment certification. DOE will
address changes to OMB Control Number 1910-1400 at that time, as
necessary.
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
DOE has analyzed this regulation in accordance with the National
Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.; NEPA) and
DOE's NEPA implementing regulations (10 CFR part 1021). In this final
rule, DOE establishes test procedure amendments that it expects will be
used to develop and implement future energy conservation standards for
CWAFs. DOE has determined that this rule falls into a class of actions
that are categorically excluded from review under NEPA and DOE's
implementing regulations, because it is a rulemaking that interprets or
amends an existing rule or regulation that does not change the
environmental effect of the rule or regulation being amended.
Specifically, DOE has determined that adopting test procedures for
measuring energy efficiency of consumer products and industrial
equipment is consistent with activities identified in 10 CFR part 1021,
subpart D, appendix A, sections A5 and A6. Accordingly, neither an
environmental assessment nor an environmental impact statement is
required.
E. Review Under Executive Order 13132
Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 10,
1999), imposes certain requirements on agencies formulating and
implementing policies or regulations that preempt State law or that
have federalism implications. The Executive order requires agencies to
examine the constitutional and statutory authority supporting any
action that would limit the policymaking discretion of the States and
to carefully assess the necessity for such actions. The Executive order
also requires agencies to have an accountable process to ensure
meaningful and timely input by State
[[Page 36232]]
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
examined this final rule and has determined that it will not have a
substantial direct effect on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government. EPCA
governs and prescribes Federal preemption of State regulations as to
energy conservation for the products that are the subject of this final
rule. States can petition DOE for exemption from such preemption to the
extent, and based on criteria, set forth in EPCA. (42 U.S.C. 6297(d))
No further action is required by Executive Order 13132.
F. Review Under Executive Order 12988
Regarding the review of existing regulations and the promulgation
of new regulations, section 3(a) of Executive Order 12988, ``Civil
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal
agencies the general duty to adhere to the following requirements: (1)
eliminate drafting errors and ambiguity; (2) write regulations to
minimize litigation; (3) provide a clear legal standard for affected
conduct rather than a general standard; and (4) promote simplification
and burden reduction. Section 3(b) of Executive Order 12988
specifically requires that executive agencies make every reasonable
effort to ensure that the regulation: (1) clearly specifies the
preemptive effect, if any; (2) clearly specifies any effect on existing
Federal law or regulation; (3) provides a clear legal standard for
affected conduct while promoting simplification and burden reduction;
(4) specifies the retroactive effect, if any; (5) adequately defines
key terms; and (6) addresses other important issues affecting clarity
and general draftsmanship under any guidelines issued by the Attorney
General. Section 3(c) of Executive Order 12988 requires Executive
agencies to review regulations in light of applicable standards in
sections 3(a) and 3(b) to determine whether they are met or it is
unreasonable to meet one or more of them. DOE has completed the
required review and determined that, to the extent permitted by law,
this final 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 regulatory action resulting 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 small governments. On March 18, 1997,
DOE published a statement of policy on its process for
intergovernmental consultation under UMRA. 62 FR 12820; also available
at www.energy.gov/gc/office-general-counsel. DOE examined this final
rule according to UMRA and its statement of policy and determined that
the rule contains neither an intergovernmental mandate, nor a mandate
that may result in the expenditure of $100 million or more in any year,
so these requirements do not apply.
H. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family
Policymaking Assessment for any rule that may affect family well-being.
This final rule will not have any impact on the autonomy or integrity
of the family as an institution. Accordingly, DOE has concluded that it
is not necessary to prepare a Family Policymaking Assessment.
I. Review Under Executive Order 12630
DOE has determined under Executive Order 12630, ``Governmental
Actions and Interference with Constitutionally Protected Property
Rights,'' 53 FR 8859 (March 18, 1988), that this regulation will not
result in any takings that might require compensation under the Fifth
Amendment to the U.S. Constitution.
J. Review Under Treasury and General Government Appropriations Act,
2001
Section 515 of the Treasury and General Government Appropriations
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most
disseminations of information to the public under guidelines
established by each agency pursuant to general guidelines issued by
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). Pursuant
to OMB Memorandum M-19-15, ``Improving Implementation of the
Information Quality Act'' (April 24, 2019), DOE published updated
guidelines which are available at www.energy.gov/sites/prod/files/2019/12/f70/DOE%20Final%20Updated%20IQA%20Guidelines%20Dec%202019.pdf. DOE
has reviewed this final rule under the OMB and DOE guidelines and has
concluded that it is consistent with applicable policies in those
guidelines.
K. Review Under Executive Order 13211
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355
(May 22, 2001), requires Federal agencies to prepare and submit to OMB,
a Statement of Energy Effects for any significant energy action. A
``significant energy action'' is defined as any action by an agency
that promulgated or is expected to lead to promulgation of a final
rule, and that: (1) is a significant regulatory action under Executive
Order 12866, or any successor order; and (2) is likely to have a
significant adverse effect on the supply, distribution, or use of
energy; or (3) is designated by the Administrator of OIRA as a
significant energy action. For any significant energy action, the
agency must give a detailed statement of any adverse effects on energy
supply, distribution, or use if the regulation is implemented, and of
reasonable alternatives to the action and their expected benefits on
energy supply, distribution, and use.
This regulatory action to amend the test procedure for measuring
the energy efficiency of CWAFs is not a significant regulatory action
under Executive Order 12866. Moreover, it would not have a significant
adverse effect on the supply, distribution, or use of energy, nor has
it been designated as a significant energy action by the Administrator
of OIRA. Therefore, it is not a significant energy
[[Page 36233]]
action, and, accordingly, DOE has not prepared a Statement of Energy
Effects.
L. Review Under Section 32 of the Federal Energy Administration Act of
1974
Under section 301 of the Department of Energy Organization Act
(Pub. L. 95-91; 42 U.S.C. 7101), DOE must comply with section 32 of the
Federal Energy Administration Act of 1974, as amended by the Federal
Energy Administration Authorization Act of 1977. (15 U.S.C. 788; FEAA)
Section 32 essentially provides in relevant part that, where a proposed
rule authorizes or requires use of commercial standards, the notice of
proposed rulemaking must inform the public of the use and background of
such standards. In addition, section 32(c) requires DOE to consult with
the Attorney General and the Chairman of the Federal Trade Commission
(FTC) concerning the impact of the commercial or industry standards on
competition.
The amendments to the Federal test procedure for CWAFs contained in
this final rule adopt testing methods contained in certain sections of
the following commercial standards: AHRI 1500-2015 (which in turn
references ASTM D240-09, ASTM D396-14a, ASTM D4809-09a, and ASTM D5291-
10), ANSI Z21.47-2021 (which in turn references ANSI/ASME PTC 19.3-1974
(R2004)), ANSI/ASHRAE 103-2022, and UL 727-2018 (which in turn
references ASTM E230/E230M-17 and NFPA 97-2003). DOE 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., whether they
were developed in a manner that fully provides for public
participation, comment, and review). DOE has consulted with both the
Attorney General and the Chairman of the FTC about the impact on
competition of using the methods contained in these standards and has
received no comments objecting to their use.
M. Congressional Notification
As required by 5 U.S.C. 801, DOE will report to Congress on the
promulgation of this rule before its effective date. The report will
state that it has been determined that the final rule is not a ``major
rule'' as defined by 5 U.S.C. 804(2).
N. Description of Materials Incorporated by Reference
In this final rule, DOE incorporates by reference the following
test standards:
AHRI 1500-2015 provides instruction for how to perform fuel oil
analysis and for how to calculate flue loss of oil-fired CWAFs.
Copies of AHRI 1500-2015 can be obtained from the Air-Conditioning,
Heating, and Refrigeration Institute (AHRI), 2311 Wilson Blvd., Suite
400, Arlington, VA 22201, (703) 524-8800, or online at:
www.ahrinet.org.
ANSI Z21.47-2021 provides instruction for how to test gas-fired
CWAFs.
ANSI/ASHRAE 103-2022 provides instruction for how to test
residential furnaces and boilers, which DOE is referencing for the
purpose of providing instruction for testing condensing gas-fired
CWAFs.
ANSI/ASME PTC 19.3-1974 (R2004) is referenced by ANSI Z21.47-2021
and specifies thermocouple requirements for when testing gas-fired
CWAFs.
Copies of ANSI Z21.47-2021, ANSI/ASHRAE 103-2022, and ANSI/ASME PTC
19.3-1974 (R2004), can be obtained the from the American National
Standards Institute (ANSI), 25 W 43rd Street, 4th Floor, New York, NY
10036, (212) 642-4900, or online at: www.webstore.ansi.org.
ASTM D240-09 is referenced in AHRI 1500-2015, and it contains fuel
oil heating value requirements.
ASTM D396-14a is referenced in AHRI 1500-2015, and it contains
general fuel oil requirements.
ASTM D4809-09a is referenced in AHRI 1500-2015, and it contains
fuel oil hydrogen and carbon content requirements.
ASTM D5291-10 is referenced in AHRI 1500-2015, and it contains fuel
oil density requirements.
ASTM E230/E230M-17 is referenced in UL 727-2018, and it specifies
thermocouple requirements for when testing oil-fired CWAFs.
Copies of ASTM D240-09, ASTM D396-14a, ASTM D4809-09a, ASTM D5291-
10, and ASTM E230/E230M-17 can be obtained from ASTM International, 100
Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428, (877)
909-2786 or online at: www.astm.org.
NFPA 97-2003 is referenced in UL 727-2018 and provides definitions
for the terms ``combustible'' and ``noncombustible.''
Copies of NFPA 97-2003 can be obtained from the National Fire
Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA 02169-
7471, 1-800-344-3555 or online at: www.nfpa.org.
UL 727-2018 provides instruction for how to test oil-fired CWAFs.
Copies of UL 727-2018 can be obtained from Underwriters
Laboratories, Inc. (UL), 333 Pfingsten Road, Northbrook, IL 60062,
(847) 272-8800, or online at: www.standardscatalog.ul.com.
V. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this final
rule.
List of Subjects in 10 CFR Part 431
Administrative practice and procedure, Confidential business
information, Energy conservation test procedures, Incorporation by
reference, and Reporting and recordkeeping requirements.
Signing Authority
This document of the Department of Energy was signed on May 22,
2023, by Francisco Alejandro Moreno, Acting Assistant Secretary for
Energy Efficiency and Renewable Energy, pursuant to delegated authority
from the Secretary of Energy. That document with the original signature
and date is maintained by DOE. For administrative purposes only, and in
compliance with requirements of the Office of the Federal Register, the
undersigned DOE Federal Register Liaison Officer has been authorized to
sign and submit the document in electronic format for publication, as
an official document of the Department of Energy. This administrative
process in no way alters the legal effect of this document upon
publication in the Federal Register.
Signed in Washington, DC, on May 23, 2023.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
For the reasons stated in the preamble, DOE amends part 431 of
chapter II of title 10, Code of Federal Regulations as set forth below:
PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND
INDUSTRIAL EQUIPMENT
0
1. The authority citation for part 431 continues to read as follows:
Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.
0
2. Amend Sec. 431.72 by adding in alphabetical order a definition for
``Thermal efficiency two'' to read as follows:
Sec. 431.72 Definitions concerning commercial warm air furnaces.
* * * * *
Thermal efficiency two for a commercial warm air furnace equals 100
[[Page 36234]]
percent minus percent flue loss and jacket loss.
* * * * *
0
3. Revise Sec. 431.75 to read as follows:
Sec. 431.75 Materials incorporated by reference.
(a) Certain material is incorporated by reference into this subpart
with the approval of the Director of the Federal Register in accordance
with 5 U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other
than that specified in this section, DOE must publish a document in the
Federal Register and the material must be available to the public. All
approved incorporation by reference (IBR) material is available for
inspection at DOE, and at the National Archives and Records
Administration (NARA). Contact DOE at: the U.S. Department of Energy,
Office of Energy Efficiency and Renewable Energy, Building Technologies
Program, 1000 Independence Ave. SW, EE-5B, Washington, DC 20585, (202)
586-9127, [email protected], www.energy.gov/eere/buildings/building-technologies-office. For information on the availability of this
material at NARA, visit: www.archives.gov/federal-register/cfr/ibr-locations.html or email: [email protected]. The material may be
obtained from the sources in the following paragraphs of this section.
(b) AHRI. Air-Conditioning, Heating, and Refrigeration Institute,
2311 Wilson Blvd., Suite 400, Arlington, VA 22201, (703) 524-8800, or
online at: www.ahrinet.org.
(1) ANSI/AHRI 1500-2015 (``AHRI 1500-2015''), Performance Rating of
Commercial Space Heating Boilers, ANSI-approved November 28, 2014; IBR
approved for appendix A 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 online at:
www.ansi.org.
(1) CSA/ANSI Z21.47:21, (``ANSI Z21.47-2021''), Gas-fired central
furnaces, ANSI-approved April 21, 2021; IBR approved for appendices A
and B to this subpart.
(2) [Reserved]
(d) ASHRAE. American Society of Heating, Refrigerating and Air-
Conditioning Engineers Inc., 180 Technology Parkway NW, Peachtree
Corners, Georgia 30092, (404) 636-8400, or online at: www.ashrae.org.
(1) ANSI/ASHRAE 103-2022 (``ASHRAE 103-2022''), Method of Testing
for Annual Fuel Utilization Efficiency of Residential Central Furnaces
and Boilers, approved January 10, 2022; IBR approved for appendix A to
this subpart.
(2) [Reserved]
(e) ASME. American Society of Mechanical Engineers, Service Center,
22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007, (973) 882-1170, or
online at: www.asme.org.
(1) ANSI/ASME PTC 19.3-1974 (R2004), Supplement to ASME Performance
Test Codes: Part 3: Temperature Measurement, Instruments and Apparatus,
reaffirmed 2004; IBR approved for appendix A to this subpart.
(2) [Reserved]
(f) ASTM. ASTM International, 100 Barr Harbor Drive, P.O. Box C700,
West Conshohocken, PA 19428, (877) 909-2786, or online at:
www.astm.org/.
(1) ASTM D240-09, Standard Test Method for Heat of Combustion of
Liquid Hydrocarbon Fuels by Bomb Calorimeter, approved July 1, 2009;
IBR approved for appendix A to this subpart.
(2) ASTM D396-14a, Standard Specification for Fuel Oils, approved
October 1, 2014; IBR approved for appendix A to this subpart.
(3) ASTM D4809-09a, Standard Test Method for Heat of Combustion of
Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method);
approved September 1, 2009; IBR approved for appendix A to this
subpart.
(4) ASTM D5291-10, Standard Test Methods for Instrumental
Determination of Carbon, Hydrogen, and Nitrogen in Petroleum Products
and Lubricants, approved May 1, 2010; IBR approved for appendix A to
this subpart.
(5) ASTM E230/E230M-17 (``ASTM E230/E230M-17''), Standard
Specification for Temperature-Electromotive Force (emf) Tables for
Standardized Thermocouples, approved November 1, 2017; IBR approved for
appendix A to this subpart.
(g) NFPA. National Fire Protection Association, 1 Batterymarch
Park, Quincy, MA 02169-7471, 1-800-344-3555, or online at:
www.nfpa.org.
(1) NFPA 97 (``NFPA 97-2003''), Standard Glossary of Terms Relating
to Chimneys, Vents, and Heat-Producing Appliances; copyright 2023; IBR
approved for appendix A to this subpart.
(2) [Reserved]
(h) UL. Underwriters Laboratories, Inc., 333 Pfingsten Road,
Northbrook, IL 60062, (847) 272-8800, or online at: www.ul.com.
(1) UL 727 (``UL 727-2018''), Standard for Safety Oil-Fired Central
Furnaces, Tenth Edition, published January 31, 2018; IBR approved for
appendix A to this subpart.
(2) [Reserved]
0
4. Revise Sec. 431.76 to read as follows:
Sec. 431.76 Uniform test method for the measurement of energy
efficiency of commercial warm air furnaces.
(a) Scope. This section prescribes the test requirements used to
measure the energy efficiency of commercial warm air furnaces with a
rated maximum input of 225,000 Btu per hour or more.
(b) Testing and calculations--(1) Thermal efficiency. Test in
accordance with appendix A to subpart D of this part when making
representations of thermal efficiency.
(2) Thermal efficiency two. Test in accordance with appendix B to
subpart D of this part when making representations of thermal
efficiency two.
0
5. Appendix A to subpart D of part 431 is added to read as follows:
Appendix A to Subpart D of Part 431--Uniform Test Method for
Measurement of the Energy Efficiency of Commercial Warm Air Furnaces
(Thermal Efficiency)
Note: On and after May 28, 2024, any representations made with
respect to the energy use or efficiency of commercial warm air
furnaces must be made in accordance with the results of testing
pursuant to this section. At that time, manufacturers must use the
relevant procedures specified in this appendix, which reference ANSI
Z21.47-2021, ASHRAE 103-2022, UL 727-2018, or AHRI 1500-2015. On and
after July 3, 2023 and prior to May 28, 2024, manufacturers must
test commercial warm air furnaces in accordance with this appendix
or 10 CFR 431.76 as it appeared on January 1, 2023. DOE notes that,
because testing under this section is required as of May 28, 2024,
manufacturers may wish to begin using this amended test procedure as
soon as possible. Any representations made with respect to the
energy use or efficiency of such commercial warm air furnaces must
be made in accordance with whichever version is selected.
Manufacturers must use the results of testing under appendix B
to this subpart to determine compliance with any standards for
commercial warm air furnaces that use the thermal efficiency 2 (TE2)
metric.
0. Incorporation by reference.
In Sec. 431.75, DOE incorporated by reference the entire
standard for AHRI 1500-2015, ANSI Z21.47-2021, ASHRAE 103-2022, ASME
PTC 19.3-1974 (R2004), ASTM D240-09, ASTM D396-14a, ASTM D4809-09a,
ASTM D5291-10, ASTM E230/E230M-17, NFPA 97-2003, and UL 727-2018.
However, for standards AHRI 1500-2015, ANSI Z21.47-2021, ASHRAE 103-
2022, and UL 727-2018, only the enumerated provisions of those
documents apply to this appendix, as follows:
[[Page 36235]]
0.1 ANSI Z21.47-2021
(a) Sections 5.1, 5.1.4, 5.2, 5.3, 5.4, 5.5, 5.5.1, 5.6, and
7.2.1 as specified in section 1.1 of this appendix;
(b) Section 5.40 as specified in sections 1.1 and 3.1 of this
appendix;
(c) Section 5.2.8 as specified in section 4.1 of this appendix;
(d) Annex I as specified in section 3.1 of this appendix.
0.2 ASHRAE 103-2022
(a) Sections 7.2.2.4, 7.8, and 9.2 as specified in section 2.2
of this appendix;
(b) Sections 11.3.7.1 and 11.3.7.2 as specified in section 4.1
of this appendix.
0.3 UL 727-2018
(a) Sections 2, 3, 37, 38 and 39, 40, 40.6, 41, 42, 43.2, 44,
45, and 46 as specified in section 1.2 of this appendix;
(b) Figure 40.3 as specified in section 2.1 of this appendix.
0.4 AHRI 1500-2015
(a) Section C3.2.1.1 as specified in section 1.2 of this
appendix;
(b) Sections C7.2.4, C7.2.5, and C7.2.6.2 as specified in
section 3.2 of this appendix.
1. Test setup and Testing. Where this section prescribes use of
ANSI Z21.47-2021 or UL 727-2018, perform only the procedures
pertinent to the measurement of the steady-state efficiency, as
specified in this section.
1.1 Gas-fired commercial warm air furnaces. The test setup,
including flue requirement, instrumentation, test conditions, and
measurements for determining thermal efficiency are as specified in
section 1.3 of this appendix, and the following sections of ANSI
Z21.47-2021: 5.1 (General, including ASME PTC 19.3-1974 (R2004) as
referenced in Section 5.1.4), 5.2 (Basic test arrangements), 5.3
(Test ducts and plenums), 5.4 (Test gases), 5.5 (Test pressures and
burner adjustments), 5.6 (Static pressure and air flow adjustments),
5.40 (Thermal efficiency), and 7.2.1 (Basic test arrangements for
direct vent central furnaces). If section 1.3 of this appendix and
ANSI Z21.47-2021 have conflicting provisions (e.g., the number of
thermocouples that should be used when testing units with flue
outlets that have a cross-sectional area of 3.14 square inches or
less), follow the provisions in section 1.3 of this appendix. The
thermal efficiency test must be conducted only at the normal inlet
test pressure, as specified in section 5.5.1 of ANSI Z21.47-2021,
and at the maximum hourly Btu input rating specified by the
manufacturer for the product being tested.
1.2 Oil-fired commercial warm air furnaces. The test setup,
including flue requirement, instrumentation, test conditions, and
measurement for measuring thermal efficiency is as specified in
section 1.3 of this appendix and the following sections of UL 727-
2018: 2 (Units of Measurement), 3 (Glossary, except that the
definitions for ``combustible'' and ``non-combustible'' in sections
3.11 and 3.27 shall be as referenced in NFPA 97-2003), 37 (General),
38 and 39 (Test Installation), 40 (Instrumentation, except 40.4 and
40.6.2 through 40.6.7 which are not required for the thermal
efficiency test, and including ASTM E230/E230M-17 as referenced in
Sections 40.6), 41 (Initial Test Conditions), 42 (Combustion Test--
Burner and Furnace), 43.2 (Operation Tests), 44 (Limit Control
Cutout Test), 45 (Continuity of Operation Test), and 46 (Air Flow,
Downflow or Horizontal Furnace Test). If section 1.3 of this
appendix and UL 727-2018 have conflicting provisions (e.g., the
number of thermocouples that should be used when testing units with
flue outlets that have a cross-sectional area of 3.14 inches or
less), follow the provisions in section 1.3 of this appendix.
Conduct a fuel oil analysis for heating value, hydrogen content,
carbon content, pounds per gallon, and American Petroleum Institute
(API) gravity as specified in section C3.2.1.1 of AHRI 1500-2015,
including the applicable provisions of ASTM D240-09, ASTM D4809-09a,
ASTM D5291-10, and ASTM D396-14a, as referenced. The steady-state
combustion conditions, specified in section 42.1 of UL 727-2018, are
attained when variations of not more than 5 [deg]F in the measured
flue gas temperature occur for three consecutive readings taken 15
minutes apart.
1.3 Additional test setup requirements for gas-fired and oil-
fired commercial warm air furnaces
1.3.1 Thermocouple setup for gas-fired and oil-fired commercial
warm air furnaces with flue outlets that have a cross-sectional area
of 3.14 square inches or less. For units with flue outlets having a
cross-sectional area of 3.14 square inches or less, the flue gas
temperatures may optionally be measured using five individual
thermocouples, instead of nine thermocouples.
1.3.2 Procedure for flue gas measurements when testing units
with multiple flue outlets. For units that have multiple flue
outlets, record flue gas measurements (e.g., flue gas temperature,
CO2 in the flue gasses) separately for each individual
flue outlet and calculate a weighted-average value based on the
readings of all flue outlets. To determine the weighted average for
each measurement, first determine the input rating of the furnace
module associated with each flue outlet. Then multiply the ratio of
the input rating for the furnace module associated with each
individual flue outlet to the total nameplate input rating of the
furnace (i.e., the input rating associated with each individual flue
outlet divided by the total nameplate input rating) by that flue
outlet's respective component measurement and the sum of all of the
products of the calculations for all of the flue outlets to
determine the weighted-average values. Use the weighted-average
values to determine flue loss, and whether equilibrium conditions
are met before the official test period.
2. Additional test measurements
2.1 Determination of flue CO2 (carbon dioxide) or
O2 (oxygen) for oil-fired commercial warm air furnaces.
In addition to the flue temperature measurement specified in section
40.6.8 of UL 727-2018, locate one or two sampling tubes within six
inches downstream from the flue temperature probe (as indicated on
Figure 40.3 of UL 727-2018). If an open end tube is used, it must
project into the flue one-third of the chimney connector diameter.
If other methods of sampling the flue gas are used, place the
sampling tube so as to obtain an average sample. There must be no
air leak between the temperature probe and the sampling tube
location. Collect the flue gas sample at the same time the flue gas
temperature is recorded. The CO2 or O2
concentration of the flue gas must be as specified by the
manufacturer for the product being tested, with a tolerance of
0.1 percent. Determine the flue CO2 or
O2 using an instrument with a reading error no greater
than 0.1 percent.
2.2 Procedure for the measurement of condensate for a gas-fired
condensing commercial warm air furnace. The test procedure for the
measurement of the condensate from the flue gas under steady-state
operation must be conducted as specified in sections 7.2.2.4, 7.8,
and 9.2 of ASHRAE 103-2022 under the maximum rated input conditions.
This condensate measurement must be conducted for an additional 30
minutes of steady-state operation after completion of the steady-
state thermal efficiency test specified in section 1.1 of this
appendix.
3. Calculation of thermal efficiency
3.1 Gas-fired commercial warm air furnaces. Use the calculation
procedure specified in Section 5.40, Thermal efficiency, of ANSI
Z21.47-2021. When determining the flue loss that is used in the
calculation of thermal efficiency, the calculation method specified
in Annex I of ANSI Z21.47-2021 shall be used.
3.2 Oil-fired commercial warm air furnaces. Calculate the
percent flue loss (in percent of heat input rate) by following the
procedure specified in sections C7.2.4, C7.2.5, and C7.2.6.2 of the
AHRI 1500-2015. The thermal efficiency must be calculated as:
Thermal Efficiency (percent) = 100 percent - flue loss (in percent).
4. Procedure for the calculation of the additional heat gain and
heat loss, and adjustment to the thermal efficiency, for a
condensing commercial warm air furnace.
4.1 Calculate the latent heat gain from the condensation of the
water vapor in the flue gas, and calculate heat loss due to the flue
condensate down the drain, as specified in sections 11.3.7.1 and
11.3.7.2 of ASHRAE 103-2022, with the exception that in the equation
for the heat loss due to hot condensate flowing down the drain in
section 11.3.7.2, the assumed indoor temperature of 70 [deg]F and
the temperature term TOA must be replaced by the measured
room temperature as specified in section 5.2.8 of ANSI Z21.47.
4.2 Adjustment to the thermal efficiency for condensing
commercial warm air furnaces. Adjust the thermal efficiency as
calculated in section 3.1 of this appendix by adding the latent
gain, expressed in percent, from the condensation of the water vapor
in the flue gas, and subtracting the heat loss (due to the flue
condensate down the drain), also expressed in percent, both as
calculated in section 4.1 of this appendix, to obtain the thermal
efficiency of a condensing furnace.
0
6. Appendix B to subpart D of part 431 is added to read as follows:
[[Page 36236]]
Appendix B to Subpart D of Part 431-Uniform Test Method for Measurement
of the Energy Efficiency of Commercial Warm Air Furnaces (Thermal
Efficiency Two)
Note: Manufacturers must use the results of testing under this
appendix B to determine compliance with any standards for commercial
warm air furnaces that use the thermal efficiency 2 (TE2) metric. In
addition, manufacturers may optionally make representations of
energy use or efficiency of this equipment using TE2 as determined
using this appendix starting on July 3, 2023.
0. Incorporation by Reference.
In Sec. 431.75, DOE incorporates by reference the entire
standard ANSI Z21.47-2021. However, only section 5.40 and Appendix J
of ANSI Z21.47-2021 apply, as specified in sections 1.2 and 1.6 of
this appendix.
1. Testing
1.1 Set up and test the unit according to sections 0 through 4
of appendix A to this subpart, while operating the unit at the
maximum nameplate input rate (i.e., full load). Calculate thermal
efficiency (TE) using the procedure specified in sections 3 and 4 of
appendix A to this subpart.
1.2 For commercial warm air furnaces that are designed for
outdoor installation (including but not limited to CWAFs that are
weatherized, or approved for resistance to wind, rain, or snow), or
indoor installation within an unheated space (i.e., isolated
combustion systems), determine the jacket loss using Section 5.40
and Annex J of ANSI Z21.47-2021 while the unit is operating at the
maximum nameplate input. The jacket shall consist of the surfaces
surrounding the heating section of the furnace. The jacket includes
all surfaces separating the heating section from the supply air,
outside air, or condenser section, including the bottom surface
separating the heating section from the basepan.
1.3 For commercial warm air furnaces that are designed only for
indoor installation within a heated space, jacket loss shall be
zero. For commercial warm air furnaces that are designed for indoor
installation within a heated or unheated space, multiply the jacket
loss determined in section 1.2 of this appendix by 1.7. For all
other commercial warm air furnaces, including commercial warm air
furnaces that are designed for outdoor installation (including but
not limited to CWAFs that are weatherized, or approved for
resistance to wind, rain, or snow), multiply the jacket loss
determined in section 1.2 of this appendix by 3.3.
1.4 Subtract the jacket loss determined in section 1.3 of this
appendix from the TE determined in section 1.1 of this appendix to
determine the full-load efficiency.
1.5 Set up and test the unit according to sections 0 through 4
of appendix A to this subpart, while operating the unit at the
nameplate minimum input rate (i.e., part load). Calculate TE using
the procedure specified in sections 3 and 4 of appendix A to this
subpart.
1.6 For commercial warm air furnaces that are designed for
outdoor installation (including but not limited to CWAFs that are
weatherized, or approved for resistance to wind, rain, or snow), or
indoor installation within an unheated space (i.e., isolated
combustion systems), determine the jacket loss using Section 5.40
and Annex J of ANSI Z21.47-2021 while the unit is operating at the
minimum nameplate input. Alternatively, the jacket loss determined
in section 1.2 of this appendix at the maximum nameplate input may
be used.
1.7 For commercial warm air furnaces that are designed only for
indoor installation within a heated space, jacket loss shall be
zero. For commercial warm air furnaces that are designed for indoor
installation within a heated or unheated space, multiply the jacket
loss determined in section 1.6 of this appendix by 1.7. For all
other commercial warm air furnaces, including commercial warm air
furnaces that are designed for outdoor installation (including but
not limited to CWAFs that are weatherized, or approved for
resistance to wind, rain, or snow), multiply the jacket loss
determined in section 1.6 of this appendix by 3.3.
1.8 Subtract the jacket loss determined in section 1.7 of this
appendix from the TE determined in section 1.5 of this appendix to
determine the part-load efficiency.
1.9 Calculate TE2 by taking the average of the full-load and
part-load efficiencies as determined in sections 1.4 and 1.8 of this
appendix, respectively.
[FR Doc. 2023-11341 Filed 6-1-23; 8:45 am]
BILLING CODE 6450-01-P