[Federal Register Volume 86, Number 127 (Wednesday, July 7, 2021)]
[Proposed Rules]
[Pages 35660-35668]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-14338]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 86, No. 127 / Wednesday, July 7, 2021 /
Proposed Rules
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DEPARTMENT OF ENERGY
10 CFR Part 430
[EERE-2020-BT-TP-0041]
RIN 1904-AE15
Energy Conservation Program: Test Procedures for Consumer
Products; Early Assessment Review: Consumer Furnace Fans
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Request for information.
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SUMMARY: The U.S. Department of Energy (``DOE'') is undertaking an
early assessment review to determine whether amendments are warranted
for the test procedure for consumer furnace fans. DOE has identified
certain issues associated with the currently applicable test procedure
on which DOE is interested in receiving comment. The issues outlined in
this document mainly concern: Test settings (selection of airflow
control settings and external static pressure (``ESP'') requirement for
airflow settings other than the maximum setting); incorporation by
reference of the most recent industry test method; clarifications for
testing of certain products, including furnace fans with modulating
controls, furnace fans and modular blowers tested with electric heat
kits, certain two-stage furnaces that operate at reduced input only for
a preset period of time, dual-fuel furnaces, and certain oil-fired
furnaces; and issues related to test procedure repeatability and
reproducibility. DOE welcomes written comments from the public on any
subject within the scope of this document, including topics not raised
in this request for information (``RFI'').
DATES: Written comments and information are requested and will be
accepted on or before August 6, 2021.
ADDRESSES: Interested persons are encouraged to submit comments using
the Federal eRulemaking Portal at https://www.regulations.gov. Follow
the instructions for submitting comments. Alternatively, interested
persons may submit comments, identified by docket number EERE-2020-BT-
TP-0041, by any of the following methods:
1. Federal eRulemaking Portal: https://www.regulations.gov. Follow
the instructions for submitting comments.
2. Email: to [email protected]. Include docket number
2020-BT-TP-0041 and/or RIN 1904-AE15 in the subject line of the
message.
No telefacsimiles (``faxes'') will be accepted. For detailed
instructions on submitting comments and additional information on this
process, see section III of this document.
Although DOE has routinely accepted public comment submissions
through a variety of mechanisms, including email, postal mail, or hand
delivery/courier, the Department has found it necessary to make
temporary modifications to the comment submission process in light of
the ongoing pandemic. DOE is currently suspending receipt of public
comments via postal mail and hand delivery/courier. If a commenter
finds that this change poses an undue hardship, please contact
Appliance Standards Program staff at (202) 586-1445 to discuss the need
for alternative arrangements. Once the COVID-19 pandemic health
emergency is resolved, DOE anticipates resuming its regular options for
public comment submission, including postal mail and hand delivery/
courier.
Docket: The docket for this activity, which includes Federal
Register notices, comments, and other supporting documents/materials,
is available for review at https://www.regulations.gov. All documents
in the docket are listed in the https://www.regulations.gov index.
However, some documents listed in the index, such as those containing
information that is exempt from public disclosure, may not be publicly
available.
The docket web page can be found at: https://beta.regulations.gov/docket/EERE-2020-BT-TP-0041. The docket web page contains instructions
on how to access all documents, including public comments, in the
docket. See section III of this document for information on how to
submit comments through https://www.regulations.gov.
FOR FURTHER INFORMATION CONTACT: Ms. Catherine Rivest, U.S. Department
of Energy, Office of Energy Efficiency and Renewable Energy, Building
Technologies Office, EE-5B, 1000 Independence Avenue SW, Washington, DC
20585-0121. Telephone: (202) 586-7335. Email:
[email protected].
Mr. Pete Cochran, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121.
Telephone: (202) 586-9496. Email: [email protected].
For further information on how to submit a comment or review other
public comments and the docket, contact the Appliance and Equipment
Standards Program staff at (202) 287-1445 or by email:
[email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
A. Authority
B. Rulemaking History
II. Request for Information
A. Scope and Definitions
B. Test Procedure
1. Default Airflow-Control Settings
2. Modulating Controls and Thermostat Pairings
3. ESP Requirements for Airflow-Control Settings Other Than the
Maximum
4. ESP Limits for Electric Resistance Heat Kits
5. Updates to Industry Standards and Consensus-Based Test
Procedures
6. Tolerance on Temperature Measuring Instruments
7. Dual-Fuel Heating Products
8. Two-Stage Furnaces With Limited-Duration Reduced Stages
9. Furnaces Shipped Without Burners
10. Test Procedure Repeatability
C. Test Procedure Waivers
III. Submission of Comments
I. Introduction
DOE established an early assessment review process to conduct a
more focused analysis that would allow DOE to determine, based on
statutory criteria, whether an amended test procedure is warranted. 10
CFR part 430, subpart C, appendix A, section 8(a). This RFI requests
information and data regarding whether an amended test procedure would
more accurately and fully comply with the requirement that the test
procedure produce results that measure energy use during a
representative average use cycle for the product, and not be unduly
burdensome
[[Page 35661]]
to conduct. To inform interested parties and to facilitate this
process, DOE has identified several issues associated with the
currently applicable test procedures on which DOE is interested in
receiving comment. Based on the information received in response to the
RFI and DOE's own analysis, DOE will determine whether to proceed with
a rulemaking for an amended test procedure.
If DOE makes an initial determination that an amended test
procedure would more accurately or fully comply with statutory
requirements, or DOE's analysis is inconclusive, DOE will undertake a
rulemaking to issue an amended test procedure. If DOE makes an initial
determination based upon available evidence that an amended test
procedure would not meet the applicable statutory criteria, DOE will
engage in notice and comment rulemaking before issuing a final
determination that an amended test procedure is not warranted.
A. Authority
EPCA, 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 B \1\ of EPCA
established the Energy Conservation Program for Consumer Products Other
Than Automobiles. These products include consumer furnace fans, the
subject of this document. (42 U.S.C. 6295(f)(4)(D))
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\1\ For editorial reasons, upon codification in the U.S. Code,
Part B was redesignated Part A.
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Under EPCA, DOE's energy conservation program 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.
6291), test procedures (42 U.S.C. 6293), labeling provisions (42 U.S.C.
6294), energy conservation standards (42 U.S.C. 6295), and the
authority to require information and reports from manufacturers (42
U.S.C. 6296).
Federal energy efficiency requirements for covered products
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6297) DOE may, however, grant waivers of Federal preemption in
limited instances for particular State laws or regulations, in
accordance with the procedures and other provisions set forth under 42
U.S.C. 6297(d).
The Federal testing requirements consist of test procedures that
manufacturers of covered products must use as the basis for: (1)
Certifying to DOE that their products comply with the applicable energy
conservation standards adopted pursuant to EPCA (42 U.S.C. 6295(s)),
and (2) making representations about the efficiency of those consumer
products (42 U.S.C. 6293(c)). Similarly, DOE must use these test
procedures to determine whether the products comply with relevant
standards promulgated under EPCA. (42 U.S.C. 6295(s)) EPCA also
requires that, at least once every 7 years, DOE evaluate test
procedures for each type of covered product, including consumer furnace
fans, 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. 6293(b)(1)(A)) DOE is publishing this RFI to collect
data and information to inform its decision to satisfy the 7-year-
lookback review requirement.
B. Rulemaking History
DOE published a final rule on January 3, 2014, establishing the
test procedure for consumer furnace fans at title 10 of the Code of
Federal Regulations (``CFR'') part 430, subpart B, Appendix AA, Uniform
Test Method for Measuring the Energy Consumption of Furnace Fans
(``Appendix AA''). 79 FR 499 (``January 2014 Final Rule''). The test
procedure is applicable to air circulation fans used by weatherized and
non-weatherized gas furnaces, oil furnaces, electric furnaces, and
modular blowers.\2\ Section 1, Appendix AA. For each of these
categories, the test procedure covers both mobile home and non-mobile
home models. The test procedure is not applicable to non-ducted
products, such as whole-house ventilation systems without ductwork,
central air-conditioning condensing unit fans, room fans, and furnace
draft inducer fans.
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\2\ DOE defines the term ``modular blower'' in section 2.9 of
Appendix AA as a product which only uses single-phase electric
current, and which: (a) Is designed to be the principal air
circulation source for the living space of a residence; (b) Is not
contained within the same cabinet as a furnace or central air
conditioner; and (c) Is designed to be paired with HVAC products
that have a heat input rate of less than 225,000 Btu per hour and
cooling capacity less than 65,000 Btu per hour.
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As established in the January 2014 Final Rule, Appendix AA
incorporates by reference the definitions, test setup and equipment,
and procedures for measuring steady-state combustion efficiency from
the 2007 version of American National Standards Institute (``ANSI'')/
American Society of Heating, Refrigerating and Air Conditioning
Engineers (``ASHRAE'') Standard 103, Method of Testing for Annual Fuel
Utilization Efficiency of Residential Central Furnaces and Boilers
(``ANSI/ASHRAE 103-2007''). In addition to these provisions, Appendix
AA includes provisions for apparatuses and procedures for measuring
temperature rise, external static pressure, and furnace fan electrical
input power. Appendix AA also incorporates by reference provisions for
measuring temperature and external static pressure from ANSI/ASHRAE 37-
2009, Methods of Testing for Rating Electrically Driven Unitary Air-
Conditioning and Heat Pump Equipment (``ASHRAE 37-2009'').
In the January 2014 Final Rule, DOE determined that there is no
need to address standby and off mode energy use in the test procedure
for furnace fans, as the standby mode and off mode energy use
associated with furnace fans is measured by test procedures for the
products in which furnace fans are used (i.e., residential furnaces and
residential central air conditioners and heat pumps). 79 FR 499, 504-
505.
On October 12, 2018, DOE received a petition (``AHRI Petition'')
from the Air-Conditioning, Heating, and Refrigeration Institute
(``AHRI'') requesting that DOE consider adopting a new test procedure
and associated performance metric, ``AFUE2,'' that would combine and
replace the DOE test methods and associated performance metrics
currently required for furnace fans (i.e., Fan Energy Rating (``FER''))
and consumer furnaces (i.e., annual fuel utilization efficiency
(``AFUE''), standby mode energy consumption (PW,SB), and off
mode energy consumption (PW,OFF)). On November 14, 2018, DOE
published a notice of petition for rulemaking and requested comments to
assist DOE in its determination of whether to proceed with the
petition. 83 FR 56746. DOE received numerous comments on the petition,
which are available for review in the docket at https://www.regulations.gov/document/EERE-2018-BT-PET-0017-0004. Accordingly,
and consistent with the separate docket maintained for this matter, DOE
will publish its final decision in the Federal Register on whether to
grant or deny this petition in a separate notice. As DOE has already
requested comments on the AFUE2 performance metric through the petition
for rulemaking process, DOE is not requesting
[[Page 35662]]
additional comment on this topic in this RFI.
II. Request for Information
DOE is publishing this RFI to collect data and information during
the early assessment review to inform its decision, consistent with its
obligations under EPCA, as to whether the Department should proceed
with an amended test procedure rulemaking, and if so, to assist in the
development of proposed amendments. Accordingly, in the following
sections, DOE has identified specific issues on which it seeks input to
aid in its analysis of whether an amended test procedure for consumer
furnace fans would more accurately or fully comply with the requirement
that the test procedure produces results that measure energy use during
a representative average use cycle for the product, and not be unduly
burdensome to conduct. DOE also welcomes comments on other issues
relevant to its early assessment that may not specifically be
identified in this document.
A. Scope and Definitions
A ``furnace fan'' is ``an electrically-powered device used in a
consumer product for the purpose of circulating air through ductwork.''
10 CFR 430.2. As stated, DOE's furnace fan test procedure is applicable
to circulation fans used in weatherized and non-weatherized gas
furnaces, oil furnaces, electric furnaces, and modular blowers. Section
1, Appendix AA. The test procedure is not applicable to non-ducted
products, such as whole-house ventilation systems without ductwork,
central air-conditioning condensing unit fans, room fans, and furnace
draft inducer fans.
Section 2 of Appendix AA provides additional definitions relevant
to furnace fans through incorporating by reference the definitions of
section 3 of ASHRAE 103-2007 and defining additional terms both in
addition to and in place of those from section 3 of ASHRAE 103-2007. Of
particular relevance for this RFI (see further discussion in section
II.B.1 of this document), section 2.2 of Appendix AA defines ``Airflow-
control settings'' as ``programmed or wired control system
configurations that control a fan to achieve discrete, differing ranges
of airflow--often designated for performing a specific function (e.g.,
cooling, heating, or constant circulation)--without manual adjustment
other than interaction with a user-operable control such as a
thermostat that meets the manufacturer specifications for installed-
use. For the purposes of [the furnace fan test procedure], manufacturer
specifications for installed-use shall be found in the product
literature shipped with the unit.'' Section 2.6 of Appendix AA defines
``Default airflow-control settings'' as ``the airflow-control settings
specified for installed-use by the manufacturer. For the purposes of
[the furnace fan test procedure], manufacturer specifications for
installed-use are those specifications provided for typical consumer
installations in the product literature shipped with the product in
which the furnace fan is installed. In instances where a manufacturer
specifies multiple airflow-control settings for a given function to
account for varying installation scenarios, the highest airflow-control
setting specified for the given function shall be used for the
procedures specified in this appendix.''
Issue 1: DOE seeks comment on whether any changes are warranted to
the scope of applicable products currently covered by the test
procedure in Appendix AA, and if so, how the scope should be revised.
Issue 2: DOE seeks comment on whether any definitions in the test
procedure at Appendix AA require any revision, and if so, how the
definitions should be revised.
B. Test Procedure
Furnace fans are currently tested according to Appendix AA, which
is used to calculate the Fan Energy Rating (``FER''). FER is expressed
as watts per 1,000 cubic feet per minute of airflow (``W/1000 cfm'')
and is calculated as the estimated annual electrical energy consumption
of the furnace fan (in watt-hours) normalized by: (a) The estimated
total number of annual fan operating hours (1,870); and (b) the airflow
in the maximum airflow-control setting. For the purposes of the DOE
furnace fan test procedure, the estimated annual electrical energy
consumption is the sum of the furnace fan electrical input power (in
watts), measured separately for multiple airflow-control settings at
different ESPs representing a typical installation, multiplied by
national average operating hours associated with each setting. Section
10, Appendix AA.
1. Default Airflow-Control Settings
For furnace fans used in furnaces or modular blowers with single-
stage heating, the three airflow-control settings required to be tested
are: The maximum setting, the default constant-circulation setting, and
the default setting when operated using the maximum heat input rate.\3\
For furnace fans used in furnaces or modular blowers with multi-stage
heating or modulating heating, the airflow-control settings to be
tested are: The maximum setting; the default constant-circulation
setting; and the default setting when operated using the reduced heat
input rate. See sections 8.6.1, 8.6.2 and 8.6.3 of Appendix AA. For
both single-stage and two-stage or modulating units, if a default
constant-circulation setting is not specified, the lowest airflow-
control setting is used to represent constant circulation. See section
8.6.2, Appendix AA. In addition, if the manufacturer specifies multiple
heating airflow-control settings, the highest airflow-control setting
specified for the given function (i.e., at the maximum or reduced
input, as applicable) is used. See section 8.6.3, Appendix AA.
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\3\ For furnaces where the maximum airflow control setting is a
heating setting, the maximum airflow control setting test and the
default heating airflow control setting test would be identical, so
only two tests are required: (1) Maximum airflow (which is the same
as the default heating setting) and (2) constant circulation.
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Inquiries sent to DOE since the publication of the January 2014
Final Rule indicate that there are differing interpretations regarding
the appropriate airflow-control settings for testing, with some
manufacturers possibly interpreting the DOE test procedure as requiring
testing only the ``as-shipped'' airflow-control settings. However, as
stated in section II.A, the definition for ``Default airflow-control
setting'' specifically states that ``[i]n instances where a
manufacturer specifies multiple airflow-control settings for a given
function to account for varying installation scenarios, the highest
airflow-control setting specified for the given function shall be used
for the procedures specified in this appendix.'' Section 2.6 Appendix
AA. Further, the definition defines the default airflow-control
settings as airflow-control settings specified for installed-use by the
manufacturer, which are those specifications provided for typical
consumer installations in the product literature shipped with the
product in which the furnace fan is installed. Id. These provisions
account for manufacturer installation instructions that specify
installation of a furnace fans with a setting other than the ``as
shipped'' airflow-control settings and that specify multiple potential
settings based on varying installation scenarios. For example, a
furnace may be shipped with the low speed airflow-control setting
configured for the heating function, but the installation manual
shipped with the
[[Page 35663]]
furnace fan specifies the medium speed airflow-control setting for the
heating function for certain installations, which is the highest
airflow-control setting specified for the heating function. In this
scenario, the DOE definition for ``Default airflow-control setting''
instructs to test the medium airflow-control setting for heating,
rather than the ``as shipped'' setting (i.e., the low setting), since
there are multiple airflow-control settings for the heating function
and the medium setting is the highest setting specified. See id.
The inquiries DOE has received from manufacturers also indicate
that some manufacturers may be interpreting the test procedure to
require testing according to installation instructions printed on the
control board. DOE notes that the same control board can be used across
multiple products to reduce manufacturing complexity and cost, so
instructions provided on a control board may not be applicable to every
unit in which a control board is used, which could lead to
contradictory specifications regarding the installed use of consumer
furnace fans. For this reason, DOE specifies in the definition of
default airflow-control setting that the manufacturer specifications
for installed-use are those specifications provided for typical
consumer installations in the product literature shipped with the
product in which the furnace fan is installed.
Issue 3: DOE requests comment on whether further instruction is
needed for determining the appropriate airflow control settings for
testing.
Issue 4: In the event of conflicting airflow-control setting
information across multiple sources, DOE seeks comment on what the
hierarchy should be for following manufacturers' instructions.
In inquiries received after the January 2014 Final Rule,
manufacturers have stated that requiring testing of the highest
airflow-control setting for a given function when presented with
multiple airflow-control setting options may result in a control
configuration that is not representative of field installation.
Issue 5: DOE requests information about configuration of control
settings for field installations of furnace fans. Specifically, for
instances in which a manufacturer specifies multiple airflow-control
settings for a given function, DOE requests information and data that
could help inform which airflow-control setting would be most
representative of consumer use, such as data indicating the frequency
with which a furnace fan is installed using each of the specified
airflow-control settings.
In addition to specifying the airflow-control settings for testing,
the DOE test procedure also specifies operating conditions (e.g.,
temperature rise ranges and ESP ranges). See section 8 of Appendix AA.
In some instances, manufacturers specify that an airflow-control
setting is to be used only under certain specified conditions, which
are typically expressed as a maximum recommended ESP or temperature
rise range associated with each airflow-control setting. In such
instances, the manufacturer-specified operating conditions may not be
consistent with the operating conditions required by the DOE test
procedure. As a result, the furnace fan would be tested at conditions
outside of those specified by the manufacturer for the applicable
setting, if the airflow-control setting is one that is required to be
tested. Section 8 of Appendix AA requires measurements of the heating
setting operating within the ESP range and the temperature rise range
defined by the test procedure, regardless of the range specified by the
manufacturer. The operating conditions required by DOE are intended to
produce results that measure energy efficiency during a representative
average use cycle for furnace fans. See 79 FR 500, 504 (Jan. 3, 2014).
Moreover, testing outside the conditions specified by the
manufacturer may not be possible. Because furnaces are designed with
safety controls that will automatically shut off the furnace when the
outlet temperature reaches a certain temperature threshold, if the unit
is operated at conditions other than those it is designed for, it may
shut down before testing can be completed. For example, a thermal
cutout switch might ``trip'' during testing causing the unit to shut
down if the outlet temperature exceeds the temperature threshold of the
safety control.
Issue 6: DOE requests data on the operating conditions typically
encountered in the field for furnace fans across the various design
options and input capacities currently available on the market.
Issue 7: DOE requests information on whether and to what extent
safety shut-downs have occurred during testing.
In other cases, furnace fans have airflow-control settings that are
designated by the manufacturer as being suitable for multiple functions
(i.e., heating, cooling, circulation); however, in the field each
setting would be used only for a single function. The function that the
setting would be used for when installed varies depending on
installation needs (e.g., assignment of a given airflow-control speed
that can be used either for heating or cooling may be based on design
considerations such as the size of the cooling coil paired with the
furnace). In some field installations, the furnace fan must be
physically reconfigured or re-wired to assign a particular function to
the desired airflow-control setting. As discussed in section II.A,
Appendix AA defines airflow-control settings as being configured so
that they perform a certain function without manual adjustment other
than interaction with a user-operable control such as a thermostat that
meets the manufacturer specifications for installed use.
However, in cases where multiple functions are assigned to the same
airflow-control setting, the current test procedure could be understood
to require that the unit be tested in multiple functions, meaning that
the unit would need to be manually reconfigured or rewired during
testing. For example, for a single-stage furnace fan, if the same
airflow-control setting was designated as both the highest default heat
function and the highest default constant-circulation function, then
laboratory personnel would be required to first wire the fan motor to
conduct the heating test at that airflow control setting, and later
rewire the fan motor to conduct the constant circulation test at the
same airflow control setting. Similarly, rewiring could be required for
multi-stage or modulating furnace fans for which the same airflow
control setting was the highest airflow control setting for constant
circulation function and the highest airflow control setting for
reduced heat function, and the setting was not able to be configured
for both functions without reconfiguring or re-wiring the setting. (DOE
notes that there is no requirement to test at a specific manufacturer
specified airflow-control setting for cooling function for the DOE
test.) See sections 8.6.1.1, 8.6.1.2, and 8.6, Appendix AA. Re-
configuring or re-wiring an airflow-control setting in such a manner
would not be representative of how that unit is installed and operated
in the field and conflicts with the requirement that an airflow-control
setting perform a certain function without manual adjustment.
Issue 8: DOE seeks comment on whether there are furnace fans on the
market for which the combination of control settings required by the
DOE test procedure would require reconfiguration or re-wiring of the
unit during testing under the current DOE test procedure. DOE also
requests information on whether manufacturers have plans to introduce
such furnace
[[Page 35664]]
fans into the market. If so, DOE requests comment on whether a
hierarchy should be established to give precedence to a given function.
2. Modulating Controls and Thermostat Pairings
DOE is aware that an increasing proportion of furnace fans employ
modulating controls for heating, and constant circulation modes that
allow fan speed to continuously vary as opposed to operating at a
discrete speed for each function. These fans are characterized by
having electrically commutated brushless permanent magnet (``BPM'')
motors, which can be paired with thermostats that have the capability
to provide modulating control in order to make use of the BPM's ability
to vary its speed to maintain a constant airflow at various ESPs.
Because input from the thermostat is essential to the functioning of
these types of systems, furnace fan performance may be dependent on the
specific type of thermostat with which the system is paired as it could
vary depending on the types of control signals provided by the
thermostat. In field operation, modulating controls enable the furnace
fan to reduce its speed to match heating demand during periods of low
heating demand.
Section 8.3 of Appendix AA requires that the system operate
continuously for at least 30 minutes at each discrete airflow setting,
which would preclude dynamic response to thermostat signals that vary
more frequently than 30 minutes. In addition, there are no specific
provisions for testing the performance of the furnace fan under
modulating control conditions. Further, the furnace fan test procedure
relies on an assumed number of hours each year that the furnace fan is
in heating mode operating at a constant fan speed. See Table IV.2,
Appendix AA. A modulating furnace fan could potentially spend a portion
of these hours operating at a fan speed other than the speed required
by the test method, impacting the energy use during periods of lower
heating demand and, consequently, reduced fan speed.
Issue 9: DOE requests information about available control features
that impact fan performance. Specifically, DOE requests information and
data regarding modulating control approaches currently in use or
planned for future use, whether the performance differences of such
modulating furnace fans are currently adequately captured by the
furnace fan test procedure, and, if necessary, what new provisions
could be necessary to reflect the impact of these control features in
FER ratings. If new provisions are suggested, DOE also seeks comment on
any burdens associated with those provisions.
Issue 10: DOE requests comment on the most common type of
thermostats used by consumers, particularly with regards to furnace
fans with modulating control strategies.
DOE has also observed that some furnace fans have a ``ramping
profile'' setting that is selectable through dual in-line package
(``DIP'') switch adjustments during installation. Ramping profiles
allow a modulating furnace fan to gradually ramp up or down over time
to meet the target fan speed instead of immediately controlling to the
target fan speed. Ramping profiles are often marketed as providing
additional benefits to users by increasing dehumidification in cooling
mode, providing faster outlet temperature change in heating mode, and
reducing fan noise. As noted, section 8.3 of Appendix AA requires that
the system operate continuously for at least 30 minutes at each test
point before steady state conditions are achieved and test parameters
start to be recorded, and testing is conducted at steady-state and
would not account for any ramping period.
Issue 11: DOE requests information on the prevalence of field
installations for modulating furnace fans where dip switches are
selected to allow for ramping behavior.
Issue 12: DOE requests information on whether ramping profiles may
result in any difference in tested performance vs field performance,
and whether this difference should be captured by the furnace fans test
procedure.
3. ESP Requirements for Airflow-Control Settings Other Than the Maximum
Sections 8.6.2 and 8.6.3 of Appendix AA provide the test
requirements for taking measurements in airflow-control settings other
than the maximum airflow-control setting. Both sections state that
their respective required operating settings be maintained ``until
steady-state conditions are attained as specified in section 8.3, 8.4,
and 8.5'' of Appendix AA. Regarding ESP, sections 8.3, 8.4, and 8.5
state that stabilization is ``indicated by an external static pressure
within the range shown in Table 1.'' The ESP values in Table 1, as
indicated by the table's title, apply only to the maximum airflow-
control setting (section 8.6.1), and therefore are not applicable to
sections 8.6.2 and 8.6.3. In an accompanying statement immediately
below Table 1, Appendix AA directs that ``once the specified ESP has
been achieved, the same outlet duct restrictions shall be used for the
remainder of the furnace fan test.'' As such, the test procedure
specifies the ESP conditions in terms of the ductwork geometry when
testing at airflow-control settings other than the maximum airflow-
control setting.
Given that the ESP will vary as the airflow-control setting is
changed if the outlet duct restriction remains unchanged, the ESP
targets in Table 1 are not required to be met at the airflow-control
settings other than the maximum setting. DOE is considering whether it
would be helpful to instruct more directly that the Table 1 ESP
requirements are only applicable to the maximum airflow control
setting; for all other airflow-control settings, the required ESP is
that which results from using the same test duct restrictions as used
for the maximum airflow-control setting. Further, DOE is seeking
feedback on whether additional criteria is necessary to limit
variability in ESP readings for steady-state operation during the tests
for airflow-control settings other than the maximum airflow setting.
Issue 13: DOE requests comment on how manufacturers are currently
implementing sections 8.6.2 and 8.6.3 with respect to ESP.
Issue 14: DOE requests comments on whether it is necessary to
further clarify that the specific ESP values in Table 1 are not
required to be maintained for testing to sections 8.6.2 and 8.6.3.
Issue 15: DOE requests comments on whether additional direction is
needed as to the ESP requirement provided in the statement accompanying
Table 1, including whether additional criteria is necessary to limit
variability in ESP readings for steady-state operation during the tests
for airflow-control settings other than the maximum airflow setting,
and if so, what that direction should be.
4. ESP Limits for Electric Resistance Heat Kits
Modular blowers are not contained in the same cabinet as a furnace
or central air conditioner and are sold as stand-alone products that
can come with a variety of sizes of heating elements. During testing,
they must be paired with the electric resistance ``heat kit'' that is
likely to have the largest volume of retail sales with that basic model
of modular blower. Section 6.3, Appendix AA. An electric resistance
heat kit is a group of usually three to seven electric resistance
coils, called elements, each of which typically is rated at five
kilowatts. These heating elements can activate in stages to provide the
[[Page 35665]]
appropriate amount of heat to the conditioned space.
Section 6.3 of Appendix AA requires modular blowers to be tested
with the electric resistance heat kit with the largest volume of retail
sales with that basic model of modular blower. Section 6.6 of Appendix
AA also includes provisions for electric furnaces that use electric
resistance heat elements. With an electric resistance heat kit, some
modular blowers and electric furnaces shut off the electric resistance
heat elements beyond certain ESP limits. These ESP limits may be lower
than the ESP levels required by Appendix AA. As a result, the
resistance heat elements would not be energized during testing, making
it impossible to complete a test that reflects the electrical energy
consumption of the electric heating elements as required in section
8.6.3 of Appendix AA. Since these elements would be energized during
typical field use, the test procedure may not produce results that
measure energy efficiency during a representative average use cycle.
Issue 16: DOE requests comment on the prevalence of electric
resistance heating kits installed in modular blowers and electric
furnaces that have cutoff limits based on ESP.
Issue 17: DOE requests comment on the typical range of ESP values
at which electric resistance heat kits will automatically shut off.
Issue 18: DOE requests data on the ESP ranges that this equipment
experiences in the field and the frequency with which electric
resistance heat kits are turned off during actual operation of modular
blowers and electric furnaces.
5. Updates to Industry Standards and Consensus-Based Test Procedures
In general, DOE will adopt industry test standards as DOE test
procedures for covered equipment, unless such methodology would be
unduly burdensome to conduct or would not produce test results that
reflect the energy efficiency, energy use, water use (as specified in
EPCA) or estimated operating costs of that equipment during a
representative average use cycle. Section 8(c) of appendix A to subpart
C of 10 CFR part 430.
The current DOE test procedure for furnace fans incorporates by
reference ANSI/ASHRAE 103-2007. ANSI/ASHRAE 103-2007 is a test
procedure for residential furnaces and boilers, rather than a specific
test procedure for furnace fans, and calculates AFUE, rather than FER.
Therefore, DOE's test procedure for furnace fans in Appendix AA
includes references to only certain sections of ANSI/ASHRAE 103-2007,
including requirements for instrumentation and test apparatus setup as
well as test methodology. Appendix AA also includes additional
instructions for conducting the FER test, including instructions for
calculating FER.
In July 2017, ASHRAE published an update to ASHRAE 103, i.e., ANSI/
ASHRAE 103-2017. The 2017 version made several editorial changes to the
2007 version, including use of mandatory language and use of the
International System of units. In addition to these editorial changes,
the 2017 revision made updates to the test duct and plenum figure
(Figure 2 of ANSI/ASHRAE 103-2017) and the system number table (Table 6
of ANSI/ASHRAE 103-2017), and removed figures for surface heat transfer
and coefficient of radiation (Figures 12 and 13 of ANSI/ASHRAE 103-
2007). It also adopted an amendment made by DOE in a July 10, 2013
final rule that modified the residential furnace and boiler test
procedure to provide a means to accurately calculate AFUE for two-stage
and modulating condensing furnace and boiler models meeting the
criteria in section 9.10 of ANSI/ASHRAE 103-1993 (the version
incorporated by reference at the time of the 2013 final rule). 78 FR
41265, 41268.
Figure 2 of ANSI/ASHRAE 103-2017 was changed to reflect an
extension of the minimum length of the inlet duct from 12 inches to 18
inches. The current DOE test procedure requires that ESP taps be placed
a minimum of 12 inches from the product inlet, indicating that models
installed with a return (inlet) air duct must have a duct length
greater than 12 inches. Section 6.4.1, Appendix AA. In practice, DOE
does not expect this change to interfere with nor impact the
performance rating of consumer furnace fans, because the external
static pressure and airflow will not change with this alteration.
Additional notes were also added to Figure 2 to clarify inlet duct
construction and pressure measurement.
Issue 19: DOE seeks comment on any additional changes (not
discussed above) made in the 2017 version of ANSI/ASHRAE 103 as
compared to 2007 version currently incorporated by reference in the DOE
test procedure for furnace fans.
Issue 20: DOE requests comment on whether to update the referenced
version of ANSI/ASHRAE 103 to the 2017 version and if so, what impacts
would that have on the test procedure and test procedure results.
Issue 21: DOE seeks comment on whether its assumption that
increasing the minimum inlet duct length from 12 inches to 18 inches
will not impact the performance rating is correct and, if not, how this
duct length change would change the rating.
Issue 22: DOE seeks comment on the availability of consensus-based
test procedures for measuring the energy use of furnace fans that could
be adopted without modification and more accurately or fully comply
with the requirement that the test procedure produces results that
measure energy use during a representative average use cycle for the
product, and not be unduly burdensome to conduct.
6. Tolerance on Temperature Measuring Instruments
Section 5.1 of Appendix AA, which references Section 5.1 of ASHRAE
37-2009, requires that temperature measuring instruments must be
accurate to within 0.75 [deg]F. Section 6 of Appendix AA references
section 7 of ASHRAE 103-2007 for the test apparatus setup. Section 7.6
of ASHRAE 103-2007 includes instructions to take temperature
measurements with thermocouple grids constructed of either 5, 9, or 17
thermocouples, depending on the stack diameter. The measurement
accuracy of a thermocouple grid depends on the type and number of
thermocouples used, as well as the magnitude of the air temperature
being measured. Using the types of thermocouples commonly used in test
facilities (including ``T-type'' and ``K-type''), the measurement
accuracy required in Appendix AA is achievable with a minimum of 5
thermocouples at temperatures up to approximately 450 [deg]F.\4\ Stack
temperatures in gas-fired furnaces are unlikely to exceed this
temperature. However, DOE has observed some oil-fired furnaces with
stack temperatures exceeding 500 [deg]F. DOE is considering whether
additional specifications are required to accommodate the measurement
of stack temperatures of oil-fired furnaces to ensure the repeatability
and reproducibility of FER calculations.
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\4\ Achievement of the measurement accuracy requirement was
calculated using the thermocouple characteristics found in Table 1
of ANSI/ASTM E230/E230M-17 and assuming that the overall measurement
accuracy is equal to the measurement tolerance of individual
thermocouples of that type divided by the square root of `n', where
n is the number of thermocouples.
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Issue 23: DOE seeks comment on the number and types of
thermocouples, or other temperature measurement devices, that
laboratories use to measure the stack temperatures of oil-fired
furnaces.
Issue 24: DOE requests comment on whether stack temperatures of
gas-fired
[[Page 35666]]
furnaces are likely to exceed 450 [deg]F. If so, DOE also seeks comment
on the number and types of thermocouples or other temperature
measurement devices, that laboratories use to measure the stack
temperatures of such gas-fired furnaces.
Issue 25: DOE requests comment on the accuracy of measurement
devices currently used to test oil-fired furnaces or gas-fired furnaces
with stack temperatures exceeding 450 [deg]F.
Issue 26: DOE requests comment on any burdens that would be
associated with adding specifications to address the measurement of
outlet air temperatures greater than 450 [deg]F.
7. Dual-Fuel Heating Products
Some residential heating products include an electric heat pump and
gas burner, often referred to as dual-fuel or hybrid heating units.
These products are designed to provide heating with the heat pump and/
or gas burner, depending on the operating conditions (e.g., outdoor air
temperature and heating demand). The annual operating characteristics
of a dual-fuel product may differ significantly from a typical furnace.
This is because the inclusion of a heat pump may change the amount of
operating time necessary to meet the heating load demand when compared
with a gas burner alone, resulting in changes to the operating hours of
the fan. Therefore, the estimated national annual operating values
provided in Table IV.2 of Appendix AA may not be representative of an
average use cycle for furnaces installed in dual-fuel applications. In
addition, under the current DOE test procedure, there are no provisions
to set up or operate furnace fans as dual-fuel heating units.
Issue 27: DOE requests comment on the typical operating
characteristics of dual-fuel systems. Specifically, DOE requests
comment on what conditions dictate when the heat pump or gas burner are
providing heat, and during what conditions the heat pump and gas burner
operate simultaneously.
Issue 28: DOE requests comment on whether and how the user has
control over which heating source is used in a dual-fuel system.
8. Two-Stage Furnaces With Limited-Duration Reduced Stages
The DOE test procedure requires testing two-stage furnaces in
``reduced'' heating mode, which corresponds to burner operation at the
nameplate minimum input rating. Section 8.6.3, Appendix AA. Typically,
two-stage furnaces determine whether to operate at the reduced or
maximum input based on heating demand and are capable of operating in
reduced heating mode for extended periods of time if demand remains
low. However, DOE has identified two-stage furnace models that use the
reduced heating stage only temporarily and that ramp-up to the high
heating stage after a pre-set period of time if the call for heat from
the thermostat is not satisfied. DOE has observed that the ramp-up
period for these models may be configurable by the user, but is
temporary and shorter in duration than the time required to achieve the
steady-state conditions during a test.\5\ A ramp period that is shorter
than the DOE-required period to achieve steady-state precludes these
furnaces from completing a valid test as a two-stage furnace because
the steady-state conditions cannot be met at the reduced input rate
before the unit automatically ramps up to the maximum input rate.
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\5\ For gas and oil furnaces, Section 8.3 of Appendix AA
specifies that steady-state operation is indicated by specific
defined ranges of ESP and temperature for 3 measurements taken 15
minutes apart, for a total steady-state operation period of 30
minutes. For electric furnaces and modular blowers, Section 8.4 of
Appendix AA specifies that steady-state operation is indicated by
specific defined ranges of ESP and temperature for 4 measurements
taken 15 minutes apart, for a total steady-state operation period of
45 minutes.
---------------------------------------------------------------------------
Issue 29: DOE requests comment on how the industry currently tests
and certifies two-stage furnaces that automatically ramp up from the
reduced input to the maximum input after a set period.
Issue 30: DOE requests comment on the prevalence of two-stage
furnaces that are controlled such that they are unable to achieve
steady-state operation under the DOE test procedure in reduced heating
mode.
9. Furnaces Shipped Without Burners
DOE is aware that some furnaces are shipped without a burner and
the furnace manufacturer specifies one or multiple options for
compatible burners in product literature (e.g., brochures and
installation manuals). This is particularly common for oil-fired
furnaces. In cases where multiple burner options from multiple
manufacturers are specified, the different burners may have performance
differences that impact FER even though the various options may each
provide the same heating capacity. These burners may be constructed
differently between manufacturers, potentially resulting in different
steady-state heating efficiency and/or different airflow resistance
characteristics, both of which would impact FER. DOE's furnace fan test
procedure and certification requirements do not specify whether to test
and certify a furnace that is compatible with multiple burners with
each specified burner, or a single manufacturer-specified burner. If
different burner options are used in tests for a given oil furnace and
burner selection impacts FER, this could result in test repeatability
issues.
Issue 31: DOE requests comments on whether and by how much burner
selection can impact furnace fan performance, particularly as measured
by FER. If burner selection does impact furnace fan performance, DOE
requests comment on potential approaches for specifying burner(s) for
testing.
10. Test Procedure Repeatability
DOE understands that variations in ESP \6\ or ambient conditions
(such as dry bulb temperature or relative humidity) can affect test
results. In particular, the relative humidity and dry bulb temperature
of the test room must be measured at the beginning of the test, but
there is no specified value or tolerance that must be met. DOE seeks
comment and information on whether these factors could pose a challenge
to obtaining repeatable test results and reproducible results across
laboratories.
---------------------------------------------------------------------------
\6\ Table 1 in Section 8.6.1.2 specifies the required minimum
external static pressure in the maximum airflow-control setting by
installation type. For each installation type, the furnace fan must
be tested within a 0.05 in. w.c. range of the required ESP test
condition. ESP adjustment is accomplished by symmetrically
restricting the outlet of the test duct until the target ESP
condition is attained within tolerance.
---------------------------------------------------------------------------
Issue 32: DOE requests comment on whether stakeholders have
encountered difficulty obtaining repeatable and reproducible FER
results using Appendix AA. Specifically, DOE seeks information and data
on how significantly fluctuations in ESP and ambient conditions (within
the boundaries allowed by Appendix AA) can impact FER ratings.
C. Test Procedure Waivers
A person may seek a waiver from the test procedure requirements for
a particular basic model of a type of covered product when the basic
model for which the petition for waiver is submitted contains one or
more design characteristics that: (1) Prevent testing according to the
prescribed test procedure, or (2) cause the prescribed test procedures
to evaluate the basic model in a manner so unrepresentative of its true
energy consumption characteristics as to provide materially inaccurate
comparative data. 10 CFR 430.27(a)(1). On February 20, 2019, DOE
received a petition for waiver and an application for interim waiver
from ECR International, Inc. (``ECR'') for several
[[Page 35667]]
models of belt-driven, single-speed furnace fans designed for heating-
only applications in oil-fired warm air furnaces.\7\
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\7\ See: https://www.regulations.gov/document?D=EERE-2019-BT-WAV-0004-0001.
---------------------------------------------------------------------------
The current DOE test procedure for furnace fans does not contain
any provisions specific to ``heating-only'' units. In a notice of
proposed rulemaking published on May 15, 2012, DOE initially determined
that for heating-only furnaces, a reference system ESP of 0.50 in. w.c.
would provide test results representative of an average use cycle. 77
FR 28674, 28686. However, DOE withdrew the proposal for separate
conditions for heating-only furnace fans in a subsequent supplemental
notice of proposed rulemaking, because DOE was unable to identify
heating-only models on the market at that time that were within the
scope of the rulemaking. 78 FR 19606, 19619 (April 2, 2013). Therefore,
in the January 2014 Final Rule, DOE did not adopt separate ESP
requirements for heating-only furnace fans. See 79 FR 500, 505-506.
In its petition for waiver, ECR asserted that the furnace fan basic
models specified in its petition have design characteristics that
prevent testing of the basic model according to the test procedure
prescribed in Appendix AA. Specifically, ECR claimed that testing such
furnace fans at the ESP requirements in Appendix AA reduces airflow and
increases temperature rise to the point where the units shut off during
testing due to high temperature limits, making it impossible to reach
steady state for testing at the required conditions. On March 9, 2021,
DOE published a Decision and Order granting ECR a waiver from the
applicable test procedure at 10 CFR part 430, subpart B, appendix AA
for specified basic models of furnace fans, which specifies an
alternate test procedure (specifically it specifies alternate ESP test
conditions). 86 FR 13530. The Decision and Order provides that ECR must
test and rate such products using the alternate test procedure set
forth in the Decision and Order.\8\ Id. at 86 FR 13534-13535.
---------------------------------------------------------------------------
\8\ See: https://www.regulations.gov/document/EERE-2019-BT-WAV-0004-0015.
---------------------------------------------------------------------------
The test procedure waiver for these furnace fans basic models
provides alternate test provisions to measure energy that are
representative of real-world use conditions for the basic models
specified in the Order.
Issue 33: DOE requests feedback on whether the test procedure
waiver approach is generally appropriate for testing all basic models
of furnace fans designed for heating-only applications.
III. Submission of Comments
DOE invites all interested parties to submit in writing by the date
specified in the DATES heading, comments and information on matters
addressed in this RFI and on other matters relevant to DOE's early
assessment of whether an amended test procedure for furnace fans is
warranted and if so, what such amendments should be.
Submitting comments via https://www.regulations.gov. The https://www.regulations.gov web page requires you to provide your name and
contact information. Your contact information will be viewable to DOE
Building Technologies staff only. Your contact information will not be
publicly viewable except for your first and last names, organization
name (if any), and submitter representative name (if any). If your
comment is not processed properly because of technical difficulties,
DOE will use this information to contact you. If DOE cannot read your
comment due to technical difficulties and cannot contact you for
clarification, DOE may not be able to consider your comment.
However, your contact information will be publicly viewable if you
include it in the comment or in any documents attached to your comment.
Any information that you do not want to be publicly viewable should not
be included in your comment, nor in any document attached to your
comment. Persons viewing comments will see only first and last names,
organization names, correspondence containing comments, and any
documents submitted with the comments.
Do not submit to https://www.regulations.gov information for which
disclosure is restricted by statute, such as trade secrets and
commercial or financial information (hereinafter referred to as
Confidential Business Information (CBI)). Comments submitted through
https://www.regulations.gov cannot be claimed as CBI. Comments received
through the website will waive any CBI claims for the information
submitted. For information on submitting CBI, see the Confidential
Business Information section.
DOE processes submissions made through https://www.regulations.gov
before posting. Normally, comments will be posted within a few days of
being submitted. However, if large volumes of comments are being
processed simultaneously, your comment may not be viewable for up to
several weeks. Please keep the comment tracking number that https://www.regulations.gov provides after you have successfully uploaded your
comment.
Submitting comments via email. Comments and documents submitted via
email also will be posted to https://www.regulations.gov. If you do not
want your personal contact information to be publicly viewable, do not
include it in your comment or any accompanying documents. Instead,
provide your contact information in a cover letter. Include your first
and last names, email address, telephone number, and optional mailing
address. The cover letter will not be publicly viewable as long as it
does not include any comments.
Include contact information each time you submit comments, data,
documents, and other information to DOE. No telefacsimiles (faxes) will
be accepted.
Comments, data, and other information submitted to DOE
electronically should be provided in PDF (preferred), Microsoft Word or
Excel, WordPerfect, or text (ASCII) file format. Provide documents that
are not secured, written in English, and free of any defects or
viruses. Documents should not contain special characters or any form of
encryption and, if possible, they should carry the electronic signature
of the author.
Campaign form letters. Please submit campaign form letters by the
originating organization in batches of between 50 to 500 form letters
per PDF or as one form letter with a list of supporters' names compiled
into one or more PDFs. This reduces comment processing and posting
time.
Confidential Business Information. Pursuant to 10 CFR 1004.11, any
person submitting information that he or she believes to be
confidential and exempt by law from public disclosure should submit via
email two well-marked copies: one copy of the document marked
``confidential'' including all the information believed to be
confidential, and one copy of the document marked ``non-confidential''
with the information believed to be confidential deleted. DOE will make
its own determination about the confidential status of the information
and treat it according to its determination.
It is DOE's policy that all comments may be included in the public
docket, without change and as received, including any personal
information provided in the comments (except information deemed to be
exempt from public disclosure).
DOE considers public participation to be a very important part of
the process for developing test procedures and
[[Page 35668]]
energy conservation standards. DOE actively encourages the
participation and interaction of the public during the comment period
in each stage of this process. Interactions with and between members of
the public provide a balanced discussion of the issues and assist DOE
in the process. Anyone who wishes to be added to the DOE mailing list
to receive future notices and information about this process should
contact Appliance and Equipment Standards Program staff at (202) 287-
1445 or via email at [email protected].
Signing Authority
This document of the Department of Energy was signed on June 29,
2021, by Kelly Speakes-Backman, Principal Deputy Assistant Secretary
and 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 June 30, 2021.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
[FR Doc. 2021-14338 Filed 7-6-21; 8:45 am]
BILLING CODE 6450-01-P