# Energy Conservation Program: Energy Conservation Standards for Consumer Furnace Fans

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3A2023-22149

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** October 6, 2023
- **Citation:** 88 FR 69826

## Text

DEPARTMENT OF ENERGY
10 CFR Part 430
[EERE-2021-BT-STD-0029]
RIN 1904-AE64
Energy Conservation Program: Energy Conservation Standards for Consumer Furnace Fans

AGENCY:

Office of Energy Efficiency and Renewable Energy, Department of Energy.

ACTION:

Notification of proposed determination and request for comment.

SUMMARY:

The Energy Policy and Conservation Act, as amended (“EPCA”), prescribes energy conservation standards for various consumer products and certain commercial and industrial equipment, including consumer furnace fans. EPCA also requires the U.S. Department of Energy (“DOE”) to periodically determine whether more-stringent, amended standards would be technologically feasible and economically justified, and would result in significant energy savings. In this notification of proposed determination (“NOPD”), DOE has initially determined that it could not conclude that amended standards would be cost effective, and thus, is not proposing to amend its energy conservation standards for these products. DOE requests comment on this proposed determination and the associated analyses and results.

DATES:

Meeting:
DOE will hold a webinar upon request. Please request a public webinar no later than October 20, 2023.
See
section VII, “Public Participation,” for webinar registration information, participant instructions, and information about the capabilities available to webinar participants.

Comments:
Written comments and information are requested and will be accepted on or before December 5, 2023.

ADDRESSES:

Interested persons are encouraged to submit comments using the Federal eRulemaking Portal at
www.regulations.gov
under docket number EERE-2021-BT-STD-0029. Follow the instructions for submitting comments.

Alternatively, interested persons may submit comments, identified by docket number EERE-2021-BT-STD-0029, by any of the following methods:

(1)
Email: ConsumerFurnFan2021STD0029@ee.doe.gov.
Include the docket number EERE-2021-BT-STD-0029 in the subject line of the message.

(2)
Postal Mail:
Appliance and Equipment Standards Program, U.S. Department of Energy, Building Technologies Office, Mailstop EE-5B, 1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone: (202) 287-1445. If possible, please submit all items on a compact disc (“CD”), in which case it is not necessary to include printed copies.

(3)
Hand Delivery/Courier:
Appliance and Equipment Standards Program, U.S. Department of Energy, Building Technologies Office, 950 L'Enfant Plaza SW, 6th Floor, Washington, DC 20024. Telephone: (202) 287-1445. If possible, please submit all items on a CD, in which case it is not necessary to include printed copies.

No telefacsimiles (“faxes”) will be accepted. For detailed instructions on submitting comments and additional information on this process,
see
section VII of this document.

Docket:
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.
All documents in the docket are listed in the
www.regulations.gov
index. However, not all documents listed in the index may be publicly available, such as information that is exempt from public disclosure.

The docket web page can be found at
www.regulations.gov/docket/EERE-2021-BT-STD-0029.
The docket web page contains instructions on how to access all documents, including public comments, in the docket.
See
section VII, “Public Participation,” for further information on how to submit comments through
www.regulations.gov.

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. Email:
ApplianceStandardsQuestions@ee.doe.gov.

Mr. Matthew Schneider, U.S. Department of Energy, Office of the General Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone: (240) 597-6265. Email:
matthew.schneider@hq.doe.gov.

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:
ApplianceStandardsQuestions@ee.doe.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Synopsis of the Proposed Determination

II. Introduction

A. Authority

B. Background

1. Current Standards

2. History of Standards Rulemakings for Consumer Furnace Fans

C. Deviation From Appendix A of the Process Rule

III. General Discussion

A. General Comments

1. Comments Opposing Amended Standards for Furnace Fans

2. Comments Expressing Support for Amended Standards for Furnace Fans

B. Product Classes and Scope of Coverage

C. Test Procedure

D. Technological Feasibility

1. General

2. Maximum Technologically Feasible Levels

E. Cost Effectiveness

F. Energy Savings

1. Determination of Savings

2. Significance of Savings

G. Additional Considerations

IV. Methodology and Discussion of Related Comments

A. Market and Technology Assessment

1. Scope of Coverage

2. Technology Options

3. Impact From Other Rulemakings

a. Screened-Out Technologies

b. Remaining Technologies

4. Product Classes

B. Engineering Analysis

1. Efficiency Analysis

a. Baseline Efficiency Level

b. Intermediate Efficiency Levels

c. Maximum Technology Efficiency Levels

d. Summary of Efficiency Levels Analyzed

2. Cost Analysis

a. Teardown Analysis

b. Cost Estimation Method

3. Cost-Efficiency Results

C. Markups Analysis

D. Energy Use Analysis

E. Life-Cycle Cost and Payback Period Analysis

1. Product Cost

2. Installation Cost

3. Annual Energy Consumption

4. Energy Prices

5. Maintenance and Repair Costs

6. Product Lifetime

7. Discount Rates

8. Energy Efficiency Distribution in the No-New-Standards Case

9. Payback Period Analysis

F. Shipments Analysis

G. National Impact Analysis

1. Product Efficiency Trends

2. National Energy Savings

3. Net Present Value Analysis

H. Further Considerations Related to Backward-Inclined Impellers

V. Analytical Results and Conclusions

A. Economic Impacts on Individual Consumers

B. National Impact Analysis

1. Significance of Energy Savings

2. Net Present Value of Consumer Costs and Benefits

C. Proposed Determination

1. BPM Motor With Backward-Inclined Impellers

2. BPM Motor With Forward-Curved Impellers

3. Summary

VI. 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

D. Review Under the National Environmental Policy Act of 1969

E. Review Under Executive Order 13132

F. Review Under Executive Order 12988

G. Review Under the Unfunded Mandates Reform Act of 1995

H. Review Under the Treasury and General Government Appropriations Act, 1999

I. Review Under Executive Order 12630

J. Review Under the Treasury and General Government Appropriations Act, 2001

K. Review Under Executive Order 13211

L. Review Under the Information Quality Bulletin for Peer Review

VII. Public Participation

A. Participation in the Webinar

B. Submission of Comments

C. Issues on Which DOE Seeks Comment

VIII. Approval of the Office of the Secretary

I. Synopsis of the Proposed Determination

The Energy Policy and Conservation Act, Public Law 94-163, as amended (“EPCA”),
1

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 of EPCA
2

established the Energy Conservation Program for Consumer Products Other Than Automobiles. (42 U.S.C. 6291-6309) These products include consumer furnace fans, the subject of this NOPD. (42 U.S.C. 6295(f)(4)(D))

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 B was redesignated Part A.

DOE is issuing this NOPD pursuant to the EPCA requirement that not later than 6 years after issuance of any final rule establishing or amending a standard, DOE must publish either a notification of determination that standards for the product do not need to be amended, or a notice of proposed rulemaking (“NOPR”) including new proposed energy conservation standards (proceeding to a final rule, as appropriate). (42 U.S.C. 6295(m))

For this proposed determination, DOE analyzed consumer furnace fans subject to standards specified in 10 CFR 430.32(y). DOE first analyzed the technological feasibility of more energy efficient consumer furnace fans. For those consumer furnace fans for which DOE determined higher standards to be technologically feasible, DOE evaluated whether higher standards would be cost effective by conducting life-cycle cost (“LCC”) and payback period (“PBP”) analyses. In addition, DOE estimated energy savings that would result from potential energy conservation standards by conducting a national impacts analysis (“NIA”), in which it estimated the net present value (“NPV”) of the total costs and benefits experienced by consumers.

Based on the results of the analyses, summarized in section V of this document, DOE has tentatively determined that current standards for consumer furnace fans do not need to be amended.

II. Introduction

The following section briefly discusses the statutory authority underlying this proposed determination, as well as some of the historical background relevant to the establishment of standards for consumer furnace fans.

A. Authority

EPCA authorizes DOE to regulate the energy efficiency of a number of consumer products and certain industrial equipment. Title III, Part B 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)) Specifically, EPCA authorized DOE to establish energy conservation standards for electricity used for purpose of circulating air through duct work. (
Id.
)

The energy conservation program under EPCA consists essentially of four parts: (1) testing, (2) labeling, (3) the establishment of Federal energy conservation standards, and (4) certification and enforcement procedures. Relevant provisions of EPCA specifically 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).

Subject to certain criteria and conditions, DOE is required to develop test procedures to measure the energy efficiency, energy use, or estimated annual operating cost of each covered product. (42 U.S.C. 6295(o)(3)(A) and 42 U.S.C. 6295(r)) Manufacturers of covered products must use the prescribed DOE test procedure as the basis for certifying to DOE that their products comply with the applicable energy conservation standards adopted under EPCA and when making representations to the public regarding the energy use or efficiency of those products. (42 U.S.C. 6293(c) and 42 U.S.C. 6295(s)) Similarly, DOE must use these test procedures to determine whether the products comply with standards adopted pursuant to EPCA. (42 U.S.C. 6295(s)) The DOE test procedures for consumer furnace fans appear at title 10 of the Code of Federal Regulations (“CFR”) part 430, subpart B, appendix AA.

Federal energy conservation requirements generally supersede State laws or regulations concerning energy conservation testing, labeling, and standards. (42 U.S.C. 6297(a)-(c)) DOE may, however, grant waivers of Federal preemption for particular State laws or regulations, in accordance with the procedures and other provisions set forth under EPCA. (See 42 U.S.C. 6297(d))

Pursuant to the amendments contained in the Energy Independence and Security Act of 2007 (EISA 2007), Public Law 110-140, any final rule for new or amended energy conservation standards promulgated after July 1, 2010, is required to address standby mode and off mode energy use. (42 U.S.C. 6295(gg)(3)) Specifically, when DOE adopts a standard for a covered product after that date, it must, if justified by the criteria for adoption of standards under EPCA (42 U.S.C. 6295(o)), incorporate standby mode and off mode energy use into a single standard, or, if that is not feasible, adopt a separate standard for such energy use for that product. (42 U.S.C. 6295(gg)(3)(A)-(B)) However, DOE has previously determined that there is no need to address standby and off mode energy use in the standards for consumer furnace fans, as the standby mode and off mode energy use associated with furnace fans is accounted for by the standards and test procedures for the products in which furnace fans are used (
i.e.,
consumer furnaces and consumer central air conditioners and heat pumps). 79 FR 499, 504. DOE maintained the same approach in the proposed amended test procedure for consumer furnace fans (the “May 2022 TP NOPR”). 87 FR 29576.

DOE must periodically review its already established energy conservation standards for consumer furnace fans no later than 6 years from the issuance of a final rule establishing or amending a standard for consumer furnace fans. (42

U.S.C. 6295(m)) This 6-year look-back provision requires that DOE publish either a determination that standards do not need to be amended or a NOPR, including new proposed standards (proceeding to a final rule, as appropriate). (42 U.S.C. 6295(m)(1)) EPCA further provides that, not later than 3 years after the issuance of a final determination not to amend standards, DOE must publish either a notification of determination that standards for the product do not need to be amended, or a NOPR including new proposed energy conservation standards (proceeding to a final rule, as appropriate). (42 U.S.C. 6295(m)(3)(B)) DOE must make the analysis on which a determination is based publicly available and provide an opportunity for written comment. (42 U.S.C. 6295(m)(2))

A determination that amended standards are not needed must be based on consideration of whether amended standards will result in significant conservation of energy, are technologically feasible, and are cost effective. (42 U.S.C. 6295(m)(1)(A) and 42 U.S.C. 6295(n)(2)) Under 42 U.S.C. 6295(o)(2)(B)(i)(II), an evaluation of cost-effectiveness requires DOE to consider savings in operating costs throughout the estimated average life of the covered products in the type (or class) compared to any increase in the price, initial charges, or maintenance expenses for the covered products that are likely to result from the standard. (42 U.S.C. 6295(n)(2) and 42 U.S.C. 6295(o)(2)(B)(i)(II)) DOE is publishing this NOPD in satisfaction of the 6-year review requirement in EPCA. (42 U.S.C. 6295(m))

B. Background

1. Current Standards

In a final rule published on July 3, 2014 (“July 2014 Final Rule”), DOE prescribed the current energy conservation standards for consumer furnace fans manufactured on and after July 3, 2019. 79 FR 38130. These standards are set forth in DOE's regulations at 10 CFR 430.32(y) and are repeated in Table II.1.

Table II.1—Federal Energy Conservation Standards for Consumer Furnace Fans

Furnace fan product class

Fan energy rating
(“FER”)
(watts/1000 cubic feet per minute
(“cfm”))

Non-Weatherized, Non-Condensing Gas (“NWG-NC”)

FER = 0.044 * Q
max
+ 182.

Non-Weatherized, Condensing Gas (“NWG-C”)

FER = 0.044 * Q
max
+ 195.

Weatherized, Non-Condensing Gas (“WG-NC”)

FER = 0.044 * Q
max
+ 199.

Non-Weatherized, Non-Condensing Oil Furnace Fan (“NWO-NC”)

FER = 0.071 * Q
max
+ 382.

Non-Weatherized Electric Furnace/Modular Blower Fan (“NWEF/NWMB”)

FER = 0.044 * Q
max
+ 165.

Mobile Home Non-Weatherized, Non-Condensing Gas Furnace Fan (“MH-NWG-NC”)

FER = 0.071 * Q
max
+ 222.

Mobile Home Non-Weatherized, Condensing Gas Furnace Fan (“MH-NWG-C”)

FER = 0.071 * Q
max
+ 240.

Mobile Home Electric Furnace/Modular Blower Fan (“MH-EF/MB”)

FER = 0.044 * Q
max
+ 101.

Mobile Home Non-Weatherized Oil Furnace Fan (“MH-NWO”)
Reserved.

Mobile Home Weatherized Gas Furnace Fan (“MH-WG”)
Reserved.

2. History of Standards Rulemakings for Consumer Furnace Fans

DOE established energy conservation standards at 10 CFR 430.32(y) for furnace fans through a final rule published in the
Federal Register
on July 3, 2014 (“July 2014 Final Rule”). 79 FR 38130. As discussed in section II.A of this document, EPCA authorized DOE to establish energy conservation standards for electricity used for purpose of circulating air through duct work. (42 U.S.C. 6295(f)(4)(D)) While the statutory language allows for regulation of the electricity use of any electrically-powered device applied to residential central heating, ventilation, and air conditioning (“HVAC”) systems for the purpose of circulating air through duct work, in the July 2014 Final Rule DOE established standards only for certain furnace fans used in furnaces and modular blowers. 79 FR 38130, 38146. Compliance with the prescribed standards established for consumer furnace fans in the July 2014 Final Rule was required as of July 3, 2019. DOE's energy conservation standards for furnace fans use the fan energy rating (“FER”) metric, which is the ratio of the electrical energy consumption to airflow, expressed as watts per 1,000 cubic feet per minute of airflow (“W/1000 cfm”). 10 CFR 430.32(y). In evaluating whether amended standards for furnace fans are warranted, DOE used the test procedure for determining FER is established at 10 CFR part 430 subpart B appendix AA,
Uniform Test Method for Measuring the Energy Consumption of Furnace Fans
(“appendix AA”). In parallel to this rulemaking, DOE is considering whether amendments are warranted for the current test procedure for furnace fans. On May 13, 2022, DOE published a notice of proposed rulemaking (“NOPR”) concerning the test procedure for furnace fans (“May 2022 TP NOPR”). 87 FR 29576.

In support of the present review of the consumer furnace fans energy conservation standards, DOE published a request for information (“RFI”), which identified various issues on which DOE sought comment to inform its determination of whether the standards need to be amended on November 23, 2021 (the “November 2021 RFI”). 86 FR 66465. The following year, on November 1, 2022, DOE published a notice of availability of the preliminary technical support document (the “November 2022 Preliminary Analysis”) in the
Federal Register
. 87 FR 65687. In the November 2022 Preliminary Analysis, DOE assessed potential amended standard levels for consumer furnace fans.

On September 20, 2022, a consent decree was issued for
NRDC et al.
v.
DOE
and
New York et al.
v.
DOE
that mandated that a final agency action pertaining to energy conservation standards (
i.e.,
a final rule amending energy conservation standards or a final determination not to amend standards) must be issued by October 31, 2024.

DOE received comments in response to the November 2022 Preliminary Analysis from the interested parties listed in Table II.2.

Table II.2—November 2022 Preliminary Analysis Comments

Commenter(s)
Reference in this NOPD

Comment No.
in the docket

Commenter type

Air Conditioning, Heating and Refrigeration Institute
AHRI
23
Trade Association.

Appliance Standards Awareness Project, American Council for an Energy-Efficient Economy, National Consumer Law Center, Natural Resources Defense Council
Joint Commenters
20
Efficiency Organization.

Carrier Global Corporation
Carrier
19
Manufacturer.

Charles Beach
Beach
16
Individual.

Daikin Comfort Technologies
Daikin
* 26
Manufacturer.

Lennox International Inc
Lennox
24
Manufacturer.

Morrison Products Inc
Morrison
27
Manufacturer.

Nidec Motors
Nidec
* 26
Manufacturer.

Northwest Energy Efficiency Alliance
NEEA
25
Efficiency Organization.

Pacific Gas and Electric Company, San Diego Gas and Electric, Southern California Edison
CA IOUs
21
Utility.

Rheem Manufacturing Company
Rheem
* 26
Manufacturer.

Trane Technologies
Trane
22
Manufacturer.

Weil-McLain Technologies
Weil-McLain
* 26
Manufacturer.

* Comment No. 26 corresponds to the transcript for the webinar held December 5, 2022. These commenters made oral comments during the public meeting that are summarized and discussed in this document.

Any oral comments provided during the webinar that are not substantively addressed by written comments are summarized and cited separately throughout this NOPD. A parenthetical reference at the end of a comment quotation or paraphrase provides the location of the item in the public record.
3

3
The parenthetical reference provides a reference for information located in the docket. (Docket No., which is maintained at
www.regulations.gov
). The references are arranged as follows: (commenter name, comment docket ID number, page of that document).

C. Deviation From Appendix A of the Process Rule

In accordance with section 3(a) of 10 CFR part 430, subpart C, appendix A (“appendix A”), DOE notes that it is deviating from the provision in the appendix A regarding the pre-NOPR and NOPR stages for an energy conservation standards rulemaking.

Section 6(f)(2) of the appendix A specifies that the length of the public comment period for a NOPR will be not less than 75 calendar days. For this NOPD, DOE has opted instead to provide a 60-day comment period, as required by EPCA. 42 U.S.C. 6295(p). DOE is opting to deviate from the 75-day comment period because stakeholders have already been afforded an opportunity to provide comments on this rulemaking. As noted previously, DOE requested comment on various issues pertaining to this standards rulemaking in the November 2021 RFI, a November 2022 preliminary analysis, and collectively provided stakeholders with more than a 90 days to comment. 86 FR 66465 and 87 FR 65687. Therefore, DOE believes a 60-day comment period is appropriate and will provide interested parties with a meaningful opportunity to comment on the proposed determination.

III. General Discussion

DOE developed this proposed determination after considering comments, data, and information from interested parties that represent a variety of interests. This notice addresses issues raised by these commenters.

A. General Comments

1. Comments Opposing Amended Standards for Furnace Fans

In response to the November 2022 Preliminary Analysis, several commenters expressed opposition to amending standards for consumer furnace fans.

Trane commented that it does not support adopting efficiency level (“EL”) 1 for consumer furnace fan standards because the assumptions used in the TSD are flawed and when corrected will result in much smaller energy savings, higher consumer costs, and undue burden to manufacturers who will need to redesign all furnaces to adopt backward-inclined impellers. (Trane, No. 22 at p. 1) Trane commented that EL 1 analyzed in the November 2022 Preliminary Analysis fails to meet: (1) the energy savings threshold because the energy savings outlined in the TSD are overstated; (2) the technological feasibility requirement because there is a need for additional technology development before EL 1 is feasible; and (3) the economic justification criteria. Specifically, Trane stated that EL 1 is not economically justified for the following reasons: (1) the negative economic impact will be significant in terms of manufacturer redesign costs (for relatively small energy savings); (2) consumers will face higher product and installation costs; (3) consumers will encounter negative lifetime operating cost savings and energy savings will be lower than DOE predicted; (4) there will be negative impacts on safety and efficiency due to changes in airflow patterns (impacting utility or performance); and (5) the potential for lessening of competition will be increased because units with backward-inclined impellers do not currently exist. Trane therefore commented that the use of EL 1 should not be considered for furnace fans. (
Id.
at p. 4) Morrison commented that DOE's values for the product cost increase were undercounted, the energy savings were overestimated, and the resulting benefit to consumers would be half of the values that DOE projects. Therefore, Morrison concluded that DOE underestimated the LCC and PBP in the November 2022 Preliminary Analysis, and that the actual numbers will reflect a net cost for more consumers than currently projected. (Morrison, No. 27 at p. 4) Lennox recommended DOE conclude that no new furnace fan standards are warranted for the NWG-NC, NWG-C, and WG-NC product classes due to very high levels of consumers experiencing net costs from potential amended standards. Lennox noted that for NWG-NC and NWG-C, 44 percent and 48 percent, respectively, of consumers experience a net cost, while for WG-NC, 26 percent of consumers experience a net cost. Lennox also commented that for the NWO-NC product class, although the payback period and percent of consumers experiencing a net cost are favorable for

EL 1, the energy savings associated with these products is minimal (0.00003 quads) and does not meet the criteria of significant energy savings, and therefore amended standards are not likely warranted. (Lennox, No. 24 at p. 2) Lennox also commented that the feasible technologies available for furnace fans have not changed since the last furnace fan standards rulemaking in 2019, but equipment costs have increased over the same time period due to inflation and supply chain issues. Lennox stated that many consumers have been adversely impacted by the COVID-19 pandemic, and increasing furnace fan equipment costs with new efficiency standards is both ill-advised and economically unjustified at this time. (
Id.
at p. 2)

AHRI stated that while the simple payback period of many maximum technology feasible (“max-tech”) furnace fans appears to be favorable, almost every class of fan provides minimal average cost savings to consumers and projections showing that, in all but one case, over 44 percent of consumers will experience a net cost. AHRI commented that this cost, combined with AHRI's concerns about the misrepresentation of the cost of products with a backward-inclined impeller, lead AHRI to expect that the true percentage of affected consumers will be higher than stated. (AHRI, No. 23 at p. 3)

Morrison recommended that DOE consider the timing and length of analysis periods for complex rulemaking documents, as the public comment period for this rulemaking was at a time of year in which under-staffing is common, and, as a result, Morrison stated that it is unable to guarantee the thoroughness and attention to detail of its response to this rulemaking. (Morrison, No. 27 at p. 6)

As discussed in section II.A of this document, DOE must periodically review its already established energy conservation standards for consumer furnace fans no later than 6 years from the issuance of a final rule establishing or amending a standard for consumer furnace fans. This 6-year look-back provision requires that DOE publish either a determination that standards do not need to be amended or a NOPR, including new proposed standards (proceeding to a final rule, as appropriate). (42 U.S.C. 6295(m)(1)) Additionally, EPCA provides specific statutory criteria for amending energy conservation standards. EPCA generally requires a public notice-and-comment process (
see
42 U.S.C. 6295(p)), which affords members of the public the opportunity to comment on the rulemaking and all documents are made publicly available at
www.regulations.gov.
As part of the process for this rulemaking, DOE carefully considers the benefits and burdens of amended standards to determine whether the amended standards are the maximum standard levels that are technologically feasible and economically justified, and would conserve a significant amount of energy, as required by EPCA (see 42 U.S.C. 6295(o)(2)-(3)). Section IV of this document outlines DOE's approach to analyzing various potential amended standard levels, which was conducted in accordance with the statutory requirements outlined in EPCA (and described above) for determining whether to establish or amend standards. Section V of this document provides the results of those analyses, as well as a detailed explanation of DOE's weighing of the benefits and burdens and the rationale for proposing not to amend standards for consumer furnace fans at this time based on the criteria specified in EPCA. Morrison stated that having separate measures of energy efficiency for furnaces and furnace fans may risk confusing consumers as to which efficiency label they should choose when purchasing equipment, in turn increasing the potential for wasted energy. (Morrison, No. 27 at p. 2) Lennox similarly commented that when consumers consider energy efficiency while purchasing residential furnaces, they evaluate the annual fuel utilization efficiency (“AFUE”) metric for consumer furnaces. Lennox commented that furnace fans typically account for less than 2 percent of the overall energy use of a residential furnace system in heating operation, and DOE furnace fan standards are not a focus of the consumer purchase decision. (Lennox, No. 24 at p. 8)

In response, DOE notes that EPCA directed DOE to consider and prescribe energy conservation standards or energy use standards for electricity used for the purposes of circulating air through ductwork. (42 U.S.C. 6295(f)(4)(D)) The AFUE metric used for furnaces does not account for the electricity used by the furnace fan to move air through ductwork. Therefore, to satisfy the requirements of EPCA, DOE established the FER test method and metric to account for the electrical energy consumption for circulating air through ductwork and will maintain AFUE and FER as separate metrics for consumer furnaces and consumer furnace fans, respectively.

2. Comments Expressing Support for Amended Standards for Furnace Fans

In response to the November 2022 Preliminary Analysis, several commenters encouraged DOE to amend standards for consumer furnace fans.

The CA IOUs commented that DOE's analyses show significant lifetime-operating-cost savings and short-payback periods for the NWO-NC, MH-NWG-NC, MH-NWG-C, and MH-NWO-NC product classes. (CA IOUs, No. 21 at p. 1) The CA IOUs stated that they support DOE's finding that brushless permanent magnet (“BPM”) motors are cost-effective for all product classes. (
Id.
at p. 1)

NEEA recommended that DOE adopt a BPM standard level for all equipment classes, including those DOE proposed in the expansion and for any additional classes that DOE could cover. NEEA commented that by raising the standard to BPM motors beyond non-weatherized gas furnaces, DOE would ensure that there are fewer applications where inefficient furnace fans are being used in the market. NEEA further commented that the market for BPM motors is mature, and the adoption of additional product classes should not negatively impact manufacturers. (NEEA, No. 24 at p. 3)

As part of the rulemaking process, DOE carefully considers the benefits and burdens of potential amended standards to determine whether the potential amended standards are the maximum standard levels that are technologically feasible and economically justified, and would conserve a significant amount of energy, as required by EPCA (see 42 U.S.C. 6295(o)(2)-(3)). Section IV of this document outlines DOE's approach to analyzing various potential amended standard levels, and section V of this document provides the results of those analyses, as well as a detailed explanation of DOE's weighing of the benefits and burdens and the rationale for proposing not to amend standards for consumer furnace fans.

B. Product Classes and Scope of Coverage

When evaluating and establishing energy conservation standards, DOE divides covered products into product classes by the type of energy used or by capacity or other performance-related features that justify differing standards. In making a determination whether a performance-related feature justifies a different standard, DOE must consider such factors as the utility of the feature to the consumer and other factors DOE determines are appropriate. (42 U.S.C.

6295(q)) The scope of coverage and product classes for this proposed determination are discussed in further detail in section IV.A.1 and IV.A.4, respectively. This proposed determination covers consumer furnace fans defined as an electrically-powered device used in a consumer product for the purpose of circulating air through ductwork. 10 CFR 430.2.

C. Test Procedure

EPCA sets forth generally applicable criteria and procedures for DOE's adoption and amendment of test procedures. (42 U.S.C. 6293) Manufacturers of covered products must use these test procedures to certify to DOE that their product complies with energy conservation standards and to quantify the efficiency of their product. (42 U.S.C. 6295(s) and 42 U.S.C. 6293(c)) The test procedure for determining FER is established at 10 CFR part 430 subpart B appendix AA,
Uniform Test Method for Measuring the Energy Consumption of Furnace Fans
(“appendix AA”). On May 13, 2022, DOE published the May 2022 TP NOPR, which proposed to amend the test procedure for consumer furnace fans. 87 FR 29576. Specifically, the May 2022 TP NOPR proposed the following changes: (1) Specify testing instructions for furnace fans incapable of operating at the required external static pressure (“ESP”). (2) Incorporate by reference the most recent versions of industry standards, ASHRAE 103-2017 and ASHRAE 37-2009 (RA 2019), in 10 CFR 430.3. (3) Define dual-fuel furnace fans and exclude them from the scope of appendix AA. (4) Change the term “default airflow control settings” to “specified airflow control settings.” (5) Add provisions to directly measure airflow. (6) Revise the ambient temperature conditions allowed during testing to between 65 degrees Fahrenheit (“°F”) and 85 °F for all units (both condensing and non-condensing). (7) Assign an allowable range of relative humidity during testing to be between 20 percent and 80 percent.
Id.
at 25979. DOE is still considering comments received in response to the May 2022 TP NOPR and has not yet finalized any updates to the test procedure.

D. Technological Feasibility

1. General

In evaluating potential amendments to energy conservation standards, DOE conducts a screening analysis based on information gathered on all current technology options and prototype designs that could improve the efficiency of the products or equipment that are the subject of the determination. As the first step in such an analysis, DOE develops a list of technology options for consideration in consultation with manufacturers, design engineers, and other interested parties. DOE then determines which of those means for improving efficiency are technologically feasible. DOE considers technologies incorporated in commercially available products or in working prototypes to be technologically feasible. Sections 6(b)(3)(i) and 7(b)(1) of appendix A to 10 CFR part 430 subpart C (“Process Rule”).

After DOE has determined that particular technology options are technologically feasible, it further evaluates each technology option in light of the following additional screening criteria: (1) practicability to manufacture, install, and service; (2) adverse impacts on product utility or availability; (3) adverse impacts on health or safety; and (4) unique-pathway proprietary technologies. Sections 6(b)(3)(ii)-(v) and 7(b)(2)-(5) of the Process Rule. Section IV.A.4 of this document discusses the results of the screening analysis for consumer furnace fans, particularly the designs DOE considered, those it screened out, and those that are the basis for the standards considered in this proposed determination.

2. Maximum Technologically Feasible Levels

As when DOE proposes to adopt a new or amended standard for a type or class of covered product, in this analysis it must determine the maximum improvement in energy efficiency or maximum reduction in energy use that is technologically feasible for such a product. (42 U.S.C. 6295(p)(1)) Accordingly, in the engineering analysis, DOE determined the maximum technologically feasible improvements in energy efficiency for consumer furnace fans, using the design parameters for the most efficient products available on the market or in working prototypes. The max-tech levels that DOE determined for this analysis are described in section IV.B of this proposed determination.

E. Cost Effectiveness

In making a determination of whether amended energy conservation standards are needed, EPCA requires DOE to consider the cost effectiveness of amended standards in the context of the savings in operating costs throughout the estimated average life of the covered product compared to any increase in the price of, or in the initial charges for, or maintenance expenses of, the covered product that are likely to result from a standard. (42 U.S.C. 6295(o)(2)(B)(i)(II))

In determining cost effectiveness of amending standards for consumer furnace fans, DOE conducted LCC and PBP analyses that estimate the costs and benefits to users from potential standards. To further inform DOE's consideration of the cost effectiveness of potential amended standards, DOE considered the NPV of total costs and benefits estimated as part of the NIA. The inputs for determining the NPV of the total costs and benefits experienced by consumers are (1) total annual installed cost, (2) total annual operating costs (energy costs and repair and maintenance costs), and (3) a discount factor to calculate the present value of costs and savings.

F. Energy Savings

1. Determination of Savings

For each efficiency level (“EL”) evaluated, DOE projected energy savings from application of the EL to the consumer furnace fans purchased in the 30-year period that begins in the assumed year of compliance with the potential standards (2030-2059). The savings are measured over the entire lifetime of the consumer furnace fans purchased in the previous 30-year period. DOE quantified the energy savings attributable to each EL as the difference in energy consumption between each standards case and the no-new-standards case. The no-new-standards case represents a projection of energy consumption that reflects how the market for a product would likely evolve in the absence of amended energy conservation standards. DOE used its NIA spreadsheet model to estimate national energy savings (NES) from potential amended or new standards for consumer furnace fans. The NIA spreadsheet model (described in section IV.G of this document) calculates energy savings in terms of site energy, which is the energy directly consumed by products at the locations where they are used. For electricity, DOE reports NES in terms of primary energy savings, which is the savings in the energy that is used to generate and transmit the site electricity. DOE also calculates NES in terms of full-fuel-cycle (FFC) energy savings. The FFC metric includes the energy consumed in extracting, processing, and transporting primary fuels (
i.e.,
coal, natural gas, petroleum fuels), and thus presents a more complete picture of the impacts of

energy conservation standards.
4

DOE's approach is based on the calculation of an FFC multiplier for each of the energy types used by covered products or equipment. For more information on FFC energy savings,
see
section IV.G of this document.

4
The FFC metric is discussed in DOE's statement of policy and notice of policy amendment. 76 FR 51282 (Aug. 18, 2011), as amended at 77 FR 49701 (Aug. 17, 2012).

2. Significance of Savings

In determining whether amended standards are needed, DOE must consider whether such standards will result in significant conservation of energy. (42 U.S.C. 6295(m)(1)(A)) The significance of energy savings offered by a new or amended energy conservation standard cannot be determined without knowledge of the specific circumstances surrounding a given rulemaking.
5

For example, some covered products and equipment have most of their energy consumption occur during periods of peak energy demand. The impacts of these products on the energy infrastructure can be more pronounced than products with relatively constant demand. Accordingly, DOE evaluates the significance of energy savings on a case-by-case basis.

5
The numeric threshold for determining the significance of energy savings established in a final rule published on February 14, 2020 (85 FR 8626, 8670) was subsequently eliminated in a final rule published on December 13, 2021 (86 FR 70892).

G. Additional Considerations

Pursuant to EPCA, absent DOE publishing a notification of determination that energy conservation standards for furnace fans do not need to be amended, DOE must issue a NOPR that includes new proposed standards. (42 U.S.C. 6295(m)(1)(B)). The new proposed standards in any such NOPR must be based on the criteria established under 42 U.S.C. 6295(o) and follow the procedures established under 42 U.S.C. 6295(p). (42 U.S.C. 6295(m)(1)(B)). The criteria in 42 U.S.C. 6295(o) require that standards be designed to achieve the maximum improvement in energy efficiency, which the Secretary determines is technologically feasible and economically justified. (42 U.S.C. 6295(o)(2)(A)). In deciding whether a proposed standard is economically justified, DOE must determine whether the benefits of the standard exceed its burdens. (42 U.S.C. 6295(o)(2)(B)(i)). DOE must make this determination after receiving comments on the proposed standard, and by considering, to the greatest extent practicable, the following seven statutory factors:

(1) The economic impact of the standard on manufacturers and consumers of the products subject to the standard;

(2) The savings in operating costs throughout the estimated average life of the covered products in the type (or class) compared to any increase in the price, initial charges for, or maintenance expenses of the covered products that are likely to result from the standard;

(3) The total projected amount of energy (or as applicable, water) savings likely to result directly from the standard;

(4) Any lessening of the utility or the performance of the covered products likely to result from the standard;

(5) The impact of any lessening of competition, as determined in writing by the Attorney General, that is likely to result from the standard;

(6) The need for national energy and water conservation; and

(7) Other factors the Secretary considers relevant.

(42 U.S.C. 6295(o)(2)(B)(i)(I)-(VII))

IV. Methodology and Discussion of Related Comments

This section addresses the analyses DOE has performed for this proposed determination with regard to consumer furnace fans. Separate subsections address each component of DOE's analyses. DOE used several analytical tools to estimate the impact of potential energy conservation standards. The first tool is a spreadsheet that calculates the LCC savings and PBP of potential energy conservation standards. The NIA uses a second spreadsheet set that provides shipments projections and calculates NES and net present value of total consumer costs and savings expected to result from potential energy conservation standards. These spreadsheet tools are available on the website:
www.regulations.gov/docket/EERE-2021-BT-STD-0029.

A. Market and Technology Assessment

DOE develops information in the market and technology assessment that provides an overall picture of the market for the products concerned, including the purpose of the products, the industry structure, manufacturers, market characteristics, and technologies used in the products. This activity includes both quantitative and qualitative assessments, based primarily on publicly available information. The subjects addressed in the market and technology assessment for this proposed determination include (1) a determination of the scope and product classes, (2) manufacturers and industry structure, (3) existing efficiency programs, (4) shipments information, (5) market and industry trends, and (6) technologies or design options that could improve the energy efficiency of consumer furnace fans. The key findings of DOE's market assessment are summarized in the following sections.

1. Scope of Coverage

In this analysis, DOE relied on the definition of consumer furnace fans in 10 CFR 430.2, which defines a consumer furnace fan as an electrically-powered device used in a consumer product for the purpose of circulating air through ductwork. Any product meeting the definition of consumer furnace fans is included in DOE's scope of coverage, though not all products within the scope of coverage may be subject to standards.

For this NOPD, DOE evaluated products within the same scope as those products for which DOE initially established energy conservation standards in the final rule published on July 3, 2014 (“July 2014 Final Rule”). 79 FR 38130. Products evaluated in this NOPD include:

• Furnace fans used in weatherized and non-weatherized gas furnaces, oil furnaces, and electric furnaces; and

• Modular blowers.

Consistent with the approach taken in the July 2014 Final Rule, products not addressed in this rulemaking include:

• Furnace fans used in other products, such as split-system central air conditioner (“CAC”) and heat pump indoor units, through-the-wall indoor units, small duct high-velocity indoor units, energy recovery ventilators, heat recovery ventilators, draft inducer fans, exhaust fans, or hydronic air handlers; and

• Fans used in any non-ducted products, such as whole-house ventilation systems without ductwork, CAC condensing unit fans, room fans, and furnace draft inducer fans because these products do not circulate air through ductwork.

DOE has previously determined that the DOE test procedure for furnace fans is not currently equipped to address fans contained in CACs, heat pumps, or other products. 79 FR 38130, 38149. Therefore, DOE has not established standards covering such products. (42 U.S.C. 6295(o)(3)) Any products that are non-ducted or that do not move air through ductwork (
e.g.,
draft inducer fans) would not meet the definition of a furnace fan and are therefore out of scope of the existing regulations.

In response to the November 2022 Preliminary Analysis, AHRI commented that fans used in packaged units should be excluded from the analysis as the energy use is already accounted for in the products' seasonal energy efficiency

ratio (“SEER”) rating. AHRI stated that including these products in the analysis of the overall quad savings would double count their contribution because they are accounted for in prior rulemakings. (AHRI, No. 23 at p. 4) Morrison commented that it does not see the need for DOE to include fans used in packaged units within the furnace fans rulemaking, as their energy use is already accounted for in SEER and heating seasonal performance factor (“HSPF”) ratings and excluding them from the rulemaking would prevent unnecessary repetition across rulemaking documents. (Morrison, No. 27 at p. 2) In response, DOE notes that for certain packaged units—WG-NC—there are existing standards at 10 CFR 430.32. In the July 2014 Final Rule, DOE assessed these products and established energy conservation standards for them. 79 FR 38130, 38209. As discussed in section II.A of this document, DOE must periodically review its already established energy conservation standards for consumer furnace fans no later than 6 years from the issuance of a final rule establishing or amending a standard for consumer furnace fans. (42 U.S.C. 6295(m)) In accordance with these provisions, DOE evaluated these products for this NOPD. DOE notes that the base-case efficiency distribution of fans used in the analysis includes presence of more-efficient furnace fans (
e.g.,
with BPM motors) in homes with higher-efficiency packaged units due to impacts from previous rulemakings. Because the energy savings considered from the furnace fan efficiency levels are measured relative to the base-case efficiencies, the savings calculated in this analysis are over and above those counted in previous rulemakings. Therefore, savings have not been double counted.

The CA IOUs further commented that DOE has previously noted that the provisions in 42 U.S.C. 6295(f)(4)(D) can encompass any electrically-powered devices used in residential HVAC products, including furnaces, and recommended that DOE investigate the savings opportunity for regulating furnace fans in air handlers. (
Id.
) Finally, the CA IOUs commented that many residential air handlers are offered for sale with permanent split-capacitor-equipped fans and are likely unable to meet the current rating for fan energy conservation standards applicable to furnace fans. They added that manufacturers readily offer air handlers with BPM motors and, therefore, a baseline technology option incorporating a BPM motor is likely feasible for air handlers. (
Id.
at pp. 5-6)

For the reasons discussed in the May 2022 TP NOPR, DOE is not proposing to include fans used in other types of HVAC products, including air-handlers, within the scope of coverage of appendix AA. 87 FR 29576, 29580. In the May 2022 TP NOPR, DOE tentatively concluded that the electrical energy consumption of fans used in the aforementioned types of HVAC products are accounted for by the seasonal energy efficiency ratio 2 (“SEER2”) and heating seasonal performance factor 2 (“HSPF2”) metrics measured by the test procedure for CACs and heat pumps at appendix M1 to subpart B of part 430 (“appendix M1”). 87 FR 29576, 29580. Therefore, DOE did not include air handlers in the scope of the test procedure rulemaking and likewise did not include them in this furnace fans rulemaking.

NEEA commented that it supported expanding coverage of furnace fans to include NWO-NC products in the analysis because of the persistence of this product class on the market and so the regulations would be more inclusive of the entire market and prevent any unfair advantage due to a gap in the regulations. NEEA also recommended that DOE include mobile home non-weatherized, non-condensing furnace fans as a covered product class, which, along with including NWO-NC, would encourage the transition to BPM motors across the furnace fan market. (NEEA, No. 24 at pp. 1-2) NEEA recommended that DOE add additional classes, such as non-weatherized, condensing oil (“NWO-C”) and weatherized, condensing gas (“WG-C”), to cover the entire consumer furnace fans market. (
Id.
at p. 2) Lennox commented that it finds the market impact of MH-NWO or WG-C furnace fans to be extremely low with minimal energy saving potential. (Lennox, No. 24 at p. 4)

DOE notes that, because it is not proposing amended standards at this time, it is not proposing to assign new standards to any product classes and will retain those classes for which standards currently exist, as shown in Table II.1. For NWO-NC furnace fans, standards currently exist and these products were included in this analysis. DOE also analyzed MH-NWO-NC furnace fans for the purposes of making this proposed determination. For other types of furnace fans, such as NWO-C and WG-C furnace fans, DOE is only aware of a very small number of products on the market. DOE has tentatively concluded that given the nascent and developing state of these products it would be premature to analyze proposed energy conservation standards at this time. Additional information on the product classes analyzed for this NOPD is included in section IV.A.4 of this document.

2. Technology Options

In the November 2022 Preliminary Analysis, DOE identified several technology options that would be expected to improve the efficiency of consumer furnace fans, as measured by the DOE test procedure. Specifically, DOE identified the following technology options as having the potential to improve the FER rating of consumer furnace fans (as measured in accordance with appendix AA), and considered these technology options further in the screening analysis:

• Housing design modifications

• Multi-stage heating components and controls
6

6
Although multi-stage heating components and controls were included in the list of technologies that can improve FER, DOE stated that DOE has tentatively found that multi-stage heating controls may not significantly improve furnace fan efficiency as measured by FER.
See
chapter 3 and chapter 5 of the Preliminary Analysis TSD.

• Airflow path design

• Constant-torque BPM (“CT-BPM”) and constant-airflow BPM (“CA-BPM”) motors

• Inverter controls for permanent split capacitor (“PSC”) motors

• Higher-efficiency fan blades

These technology options are described in detail in section 3.3.2 of the TSD accompanying the November 2022 Preliminary Analysis. In response to the November 2022 Preliminary Analysis, DOE received several comments related to these technology options. Several commenters supported DOE's tentative decision to analyze CT-BPM and CA-BPM motors together as a single design option because these motors appear to have comparable efficiency as measured by DOE's test procedure.

Lennox commented that CT-BPM and CA-BPM motors have similar efficiencies. Lennox stated that while there can be minor differences in the efficiency of BPM motors, they fall within a very narrow band for potential improvement. Lennox commented that the primary differences in performance are that a CT-BPM motor will result in reduced airflow as static pressure increases, whereas a CA-BPM motor will increase speed and power consumption to maintain airflow up to the limit of the motor capability. Lennox commented that motor efficiency as applied is more of a topographical map than a single point of operation and that BPM motors maintain efficiency

performance over their operating range. (Lennox, No. 24 at p. 5)

Additionally, AHRI commented that constant torque and constant airflow motors are similarly constructed but operate differently. AHRI commented that, given consistent external static pressure and airflow, AHRI assumes the two motor types would perform comparably within the expected margins of error. (AHRI, No. 23 at pp. 4-5) Carrier also commented that it agrees with DOE's assumption that CT-BPM and CA-BPM motors have comparable efficiencies and stated that the motors use similar construction despite being operated differently. Carrier commented that if a furnace with a CT-BPM motor were compared to a furnace with a similarly sized CA-BPM motor where both were operated at the same external static pressure and airflow, these motor types would consume the same amount of energy. (Carrier, No. 19 at p. 2) In response to Lennox, AHRI, and Carrier, DOE notes that it continued to analyze CT-BPM and CA-BPM motors together as a single design option for this current analysis.

Beach recommended that DOE include efficiency testing and standards in rudimentary equipment configuration descriptions. Beach recommended that DOE outline where and how the fan motor is placed within the equipment to avoid efficiency degradation at the spot where full furnace air flow deposits airstream dust and material on the motor windings. Beach commented that filter bypass, at a minimum, applies. (Beach, No. 16 at p. 1)

In response to comments from Beach, DOE notes that its energy conservation standards are in terms of FER, which is a performance-based metric that captures the estimated annual electrical energy consumption of the furnace fan normalized by: (a) the estimated total number of annual fan operating hours and (b) the airflow in the maximum airflow-control setting. DOE does not prescribe any design requirements for furnace fans and therefore specifying the placement and installation of the furnace fan within a furnace unit is out of the scope of DOE's regulations.

In the November 2022 Preliminary Analysis TSD, DOE stated that it tentatively did not consider two-stage and multi-stage technology options as a design pathway for improving FER in the engineering analysis based on manufacturer feedback, certification data, and testing. DOE requested data or comment regarding the relationship between staging and FER.

In response, AHRI commented that without performing a controlled study, it is difficult to properly compare a single-stage product to a two-stage product. AHRI commented that variables such as airflow design and temperature rise can affect the comparison, adding that it would be incorrect to generalize that one control type would have a distinct advantage over another. (AHRI, No. 23 at p. 5) Carrier commented that there is not adequate data to conclude whether single-stage and multi-stage controls result in different FER ratings. Carrier commented that comparison between the two control types is not straightforward due to multiple design characteristics that make each furnace model unique. Carrier stated that a controlled study is needed to eliminate variables that are unique to each model, such as airflow design and temperature rise selected. (Carrier, No. 19 at p. 2) Carrier also commented that it generally has not found multi-staging to improve FER ratings and that it does not believe one control type has a distinct advantage over the other. (
Id.
)

Trane commented that the assumption that FER values for a multi-stage furnace and a single-stage furnace are equal contradicts the 2014 TSD (EERE-2010-BT-STD-001-0111), which states that multi-staging was a technology option that significantly differed from the single-stage furnace. Trane commented that this difference affects the energy use equations, as the FER was calculated with a multi-stage furnace and energy use was calculated with a single-stage furnace. (Trane, No. 22 at p. 3)

Morrison questioned whether the lack of a benefit from multi-staging is due to FER not appropriately capturing real energy use. Morrison commented that, based on research presented in Canada's C823 efforts, average furnaces are oversized and rarely run at full capacity, leading them to use more fan energy than necessary. Morrison stated that part load operation would reduce the energy impact from oversizing and hence reduce fan energy use, and stated it is unclear why this option has been deemed not to be of benefit. (Morrison, No. 27 at p. 2)

DOE agrees with commenters that there are uncertainties related to the effectiveness of two-stage or multi-stage in improving FER. However, DOE has not received any additional data to support or disprove any impacts on FER between single and multi-stage units. Therefore, DOE has retained multi-stage heating components and controls as a technology option in the current analysis but, as discussed in section IV.B.1.a of this document, DOE did not consider two-stage or multi-stage operation as a design pathway for improving FER in the engineering analysis.

3. Impact From Other Rulemakings

Lennox commented that DOE needs to consider the total cumulative regulatory burden for consumer furnaces, as there are multiple concurrent DOE, EPA, and other regulatory actions undergoing updates. (Lennox, No. 24 at pp. 8-9) Lennox stated that DOE's consideration of cumulative regulatory burden has often been cursory and provided a list of relevant regulations: “2023 DOE Energy Conservation Standards (“ECS”) change for central air conditioners; 2023 DOE Energy Conservation Standard change for commercial air conditioners; 2023 DOE ECS for commercial warm air furnaces (“CWAFs”); EPA phase-down to lower GWP refrigerants to meet the American Innovation and Manufacturing (“AIM”) Act objectives; DOE ECS Furnace Standards rulemaking; National and Regional Cold Climate Heat Pump Specifications; DOE ECS for Three-Phase, Below 65,000 Btu/h; DOE Test Procedure for VRF Systems; EPA Energy Star 6.0+ for Residential HVAC; and EPA Energy Star 4.0 for Light Commercial HVAC.” (
Id.
) Lennox stated that proposing amended consumer furnace fan standards would contribute to the significant cumulative regulatory burden. (
Id.
at p. 9) Lennox commented that DOE needs to thoroughly consider the total cumulative regulatory burden association with any consideration of amended FER standards. Lennox commented that furnace manufacturers are in the midst of unprecedented regulatory change regarding equipment they manufacture. Lennox commented that these significant cumulative regulatory burdens provide another reason why DOE should not add additional burden by tightening consumer furnace fan regulations. Lennox reiterated that the fans are components in furnaces already regulated by DOE. (
Id.
at pp. 8-9)

AHRI asserted that DOE did not consider the impact of other ongoing rulemakings (
e.g.,
the notice of proposed rulemaking for consumer furnaces). (AHRI, No. 23 at p. 1) Morrison stated that it supports the comments submitted by AHRI advocating for the HVAC industry, as the burden for furnace manufacturers to meet compliance will be high. Morrison commented that the added burden of furnace fan ratings will challenge imminent regulations and an industry overloaded with regulations already underway, and that the schedule of regulations impedes manufacturers from attempting new

product development and innovation. (Morrison, No. 27 at pp. 1-2)

DOE is not proposing to amend the energy conservation standards for consumer furnace fans and therefore does not expect this rulemaking to contribute to the cumulative regulatory burden of manufactures.

Lennox also commented that it opposes DOE expanding the regulatory scope for electric motors into air-over motors, synchronous motors and inverter-only motors, and expanded scope electric motors (ESEMs), in particular when those motors are contained in already-regulated heating, ventilation, air conditioning, and refrigeration (“HVACR”) products. Lennox commented that DOE should continue to exempt air-over and inverter-only motors (including AC and synchronous motors) from component-level energy conservation standards regulation when these motors are used in HVACR equipment already regulated at the systems level. Lennox stated that DOE notes in the October 2022 Electric Motor Test Procedure Final Rule (87 FR 63588) that an industry test procedure DOE incorporated by reference is “not applicable to air-over electric motors that are synchronous electric motors and to air-over electric motors that are inverter-only” (10 CFR 431.25(I)). AHRI commented that DOE should refer to the comments made by NEMA on the energy conservation standards for Fans and Blowers on the issues surrounding setting multiple standards for the same product under different rulemakings in regards to the interaction between the furnace fan rulemaking and the ESEMs rulemaking. (AHRI, No. 23 at p. 5)

In the ESEM rulemaking, DOE is considering including expanded scope electric motors including certain permanent split capacitor (PSC) motors that exceed 0.25 horsepower and are single-speed. DOE understands that the vast majority of furnace fans use either electrically commutated motors (
i.e.,
“ECMs” which are also referred to as BPM motors in this rulemaking) or are multiple-speed PSC motors, both of which are out of the preliminary scope of the ESEM rulemaking. Thus, furnace fans using BPM motors or multiple-speed PSC motors will not be impacted by the ESEM rulemaking.
7

7
See Docket EERE-2020-BT-STD-0007.

Screening Analysis

DOE uses the following five screening criteria to determine which technology options are suitable for further consideration in an energy conservation standards rulemaking:

(1)
Technological feasibility.
Technologies that are not incorporated in commercial products or in commercially viable, existing prototypes will not be considered further.

(2)
Practicability to manufacture, install, and service.
If it is determined that mass production of a technology in commercial products and reliable installation and servicing of the technology could not be achieved on the scale necessary to serve the relevant market at the time of the projected compliance date of the standard, then that technology will not be considered further.

(3)
Impacts on product utility.
If a technology is determined to have a significant adverse impact on the utility of the product to subgroups of consumers, or result in the unavailability of any covered product type with performance characteristics (including reliability), features, sizes, capacities, and volumes that are substantially the same as products generally available in the United States at the time, it will not be considered further.

(4)
Safety of technologies.
If it is determined that a technology would have significant adverse impacts on health or safety, it will not be considered further.

(5)
Unique-pathway proprietary technologies.
If a technology has proprietary protection and represents a unique pathway to achieving a given efficiency level, it will not be considered further, due to the potential for monopolistic concerns.

10 CFR part 430, subpart C, appendix A, sections 6(b)(3) and 7(b).

In summary, if DOE determines that a technology, or a combination of technologies, fails to meet one or more of the listed five criteria, it will be excluded from further consideration in the engineering analysis.

a. Screened-Out Technologies

In the November 2022 Preliminary Analysis, DOE tentatively screened out housing design modifications and changes to airflow path designs from its analysis. In response, Lennox agreed with DOE's determination to screen out housing designs and airflow paths that could impact the thermal performance of the furnace and decrease consumer utility. (Lennox, No. 24 at p. 5) Carrier also indicated agreement with DOE's decision to screen out improved housing designs and airflow path designs due to their impact on overall product size, stating that they could adversely impact consumer utility and the practicality of making replacement installations. Additionally, Carrier agreed there is no quantitative data suggesting specific housing design changes provide efficiency improvements in the same cabinet width. (Carrier, No. 19 at p. 3)

The Joint Commenters commented that additional design options that increase efficiency beyond a backward-inclined impeller are currently available on the market. The Joint Commenters stated that airflow path and fan housing improvements represent potential options for improving furnace fan efficiency but noted that DOE screened out these design modifications since they could impact the thermal performance of the furnace. The Joint Commenters acknowledged this concern, but noted that one of the models exceeding EL 1 is used in a condensing furnace with an AFUE of 97 percent, suggesting manufacturers may be able to optimize the furnace fan efficiency without negatively impacting the efficiency of the furnace itself. The Joint Commenters recommended that DOE continue investigating furnace fan efficiencies and how certain design features on the current market permit furnace fan FER levels below those analyzed in the TSD. (Joint Commenters, No. 20 at pp. 2-3)

As discussed in section IV.A.2 of this document, airflow path and fan housing improvements can improve furnace fan efficiencies. However, as discussed in chapter 4 of the November 2022 Preliminary Analysis TSD, DOE does not have data that quantifies the impact of housing design modifications on FER. Additionally, DOE has found that the airflow path design can impact the performance of the larger furnace system with possible changes to the furnace efficiency as measured in AFUE. Though condensing furnaces can achieve lower FERs, DOE currently lacks the data necessary to conclude that these options will not reduce utility to consumers, and therefore has continued to screen out these technologies for this analysis.

Several commenters also suggested that backward-inclined impeller should be screened out of the current analysis. AHRI, Trane, Lennox, and Daikin raised concerns about the technological feasibility of backward-inclined impellers. AHRI commented that further analysis of backward-inclined impellers is needed, stating that while backward-inclined impellers can be considered a

mature technology in some products, it is nascent at best for consumer furnaces. AHRI commented that the analysis performed in the TSD does not capture the current state of this technology. (AHRI, No. 23 at pp. 2-3) Trane commented that the necessary backward-inclined impeller is not available for purchase and is therefore unavailable to furnace manufacturers for use in testing. (Trane, No. 22 at p. 2) Lennox commented that backward-inclined impellers are nascent technology for consumer furnaces and may not be practical for many installations. Lennox commented that DOE's analysis does not accurately portray the current state of this technology regarding residential furnace fans. Lennox stated that current furnace designs are much more compact than when DOE conducted research regarding backward-inclined impellers and there is now less space to accommodate furnace fans. Lennox commented that including backward-inclined impellers would require changes to the housing design and airflow patterns, which DOE screened out in the TSD. Lennox further commented that backward-inclined impellers are not a one-size-fits-all application. Lennox stated that changing the airflow design would require redesign and retesting on a model-by-model basis to ensure proper operation, compliance with safety standards, and product reliability. (Lennox, No. 24 at pp. 5-6) Daikin commented that replacing a forward-curved impeller with a backward-curved impeller may change the ESP of the unit and require that the unit use a larger blower wheel. Daikin commented that increasing the blower wheel diameter requires a change to the blower housing design, which was a technology option DOE screened out in the preliminary analysis. Daikin recommended that DOE evaluate the impact of backward-inclined impellers on furnace ESP. (Daikin, No. 26 at pp. 21-22) Rheem requested to know whether DOE had considered the impact of the backward-inclined impeller system on other furnace components, such as the evaporator coil or other accessories. (Rheem, No. 26 at p. 23) In contrast to these comments, Carrier stated that it uses backward-inclined impellers in non-weatherized gas furnaces that have 14-inch cabinets and AFUE ratings of 95 percent or higher. (Carrier, No. 19 at p. 1)

Manufacturers also raised concerns about potential impacts on the utility and safety of furnaces if backward-inclined impellers are used as a technology option. Carrier commented that its experiences suggest backward-inclined impellers significantly change the air profile through the furnace and, to maintain safety and reliability, the airflow must be redirected, adding that this can reduce the performance improvement from the impeller change. Carrier further commented that in applications where a larger impeller diameter cannot be accommodated, the increased rotational speed increases the operation noise of the furnace, adding that the noise generated from fan operation is an important performance selection criterion to consumers. (Carrier, No. 19 at p. 3) Lennox commented that backward-inclined impellers present many design challenges. Lennox noted that backward-inclined impellers must have significantly higher tip speeds, which require either a larger impeller diameter or higher rotational speed. However, Lennox commented that the required speed increase is outside the normal range of motors applied in furnace fans and would be likely to increase sound levels and reduce consumer utility. (Lennox, No. 24 at p. 6)

In response to these concerns, DOE notes that, even if there are only a limited number of commercially available product designs that incorporate backward-inclined impellers, they are sufficient to demonstrate technological feasibility as defined by EPCA. 10 CFR part 430, subpart C, appendix A, sections 6(b)(3)(i). Similarly, because these technologies are used in commercialized designs, DOE has determined that they can be implemented safely and reliably and with a noise level that is acceptable to consumers. DOE agrees, however, that there may be potential costs associated with potential redesign and retesting to ensure safety and to ensure acceptable noise levels, and this issue is discussed further in section IV.H of this document.

Therefore, for the current analysis, DOE tentatively screened out housing design modifications and changes to airflow path designs from its analysis but did not screen out backward-inclined impellers.

b. Remaining Technologies

After reviewing each technology, DOE did not screen out the following technology options and considers them as design options in the engineering analysis:

(1) Multi-stage heating components and controls

(2) High-efficiency fan motors (
i.e.,
use of BPM fan motors for product classes that currently use PSC motors)

(3) Inverter controls for PSC motors

(4) Higher-efficiency fan blades (backward-inclined impellers)

DOE determined that these technology options are technologically feasible because they are being used or have previously been used in commercially available products or working prototypes. DOE also finds that all of the remaining technology options meet the other screening criteria (
i.e.,
practicable to manufacture, install, and service and do not result in adverse impacts on consumer utility, product availability, health, or safety).

4. Product Classes

In general, when evaluating and establishing energy conservation standards, DOE divides the covered product into classes by (1) the type of energy used, (2) the capacity of the product, or (3) any other performance-related feature that affects energy efficiency and justifies different standard levels, considering factors such as consumer utility. (42 U.S.C. 6295(q))

DOE currently categorizes furnace fans into 10 product classes. EPCA specifies criteria for product class separation which include: (1) the type of energy consumed; (2) capacity; or (3) other performance-related features that justify a higher or lower energy conservation standard. 42 U.S.C. 6295(q) The 10 product classes currently established by DOE are differentiated by performance related features, including internal structure and application-specific design differences, as presented in Table IV.1. For this NOPD, DOE maintained these 10 classes, with the exception of a change to the mobile home non-weatherized oil furnace fan (MH-NWO) class discussed hereinafter.

Table IV.1—Existing Furnace Fan Product Classes

Product class

Non-weatherized, Non-condensing Gas Furnace Fan (NWG-NC).

Non-weatherized, Condensing Gas Furnace Fan (NWG-C).

Mobile Home Non-Weatherized, Non-condensing Gas Furnace Fan (MH-NWG-NC).

Mobile Home Non-Weatherized, Condensing Gas Furnace Fan (MH-NWG-C).

Mobile Home Electric Furnace/Modular Blower Fan (MH-EF/MB).

Non-Weatherized, Non-Condensing Oil Furnace Fan (NWO-NC).

Weatherized Non-Condensing Gas Furnace Fan (WG-NC).

Electric Furnace/Modular Blower Fan (EF/MB).

Mobile Home Weatherized Non-Condensing Gas Furnace Fan (MH-WG).*

Mobile Home Non-Weatherized Oil Furnace Fan (MH-NWO).*

* DOE created the MH-NWO and MH-MG product classes in the July 2014 Final Rule, but these classes do not currently have energy conservation standards.

Each product class title includes descriptors that indicate the internal structure and application-specific performance related features of its included products. As directed by EPCA, DOE must specify a different standard level for a type or class of products that has the same function or intended use if DOE determines that products within such group: (A) consume a different kind of energy from that consumed by other covered products within such type (or class); or (B) have a capacity or other performance-related feature which other products within such type (or class) do not have and such feature justifies a higher or lower standard. (42 U.S.C. 6295(q)(1)) Weatherized and non-weatherized are descriptors that indicate whether the HVAC product is installed outdoors or indoors, respectively. Design constraints are different for products installed indoors compared to outdoors, which impact furnace fan performance because furnace fan energy consumption is dependent on clearances and airflow path Weatherized products are packaged products that also include an internal evaporator coil, while non-weatherized products are not shipped with an evaporator coil but may be designed to be paired with one. The presence of an evaporator coil increases internal static pressure and impacts furnace fan performance and energy consumption. Weatherization (
i.e.,
the ability to be installed outdoors) is therefore a performance-related feature as outlined by EPCA.

Condensing refers to the presence of a secondary, condensing heat exchanger in addition to the primary combustion heat exchanger in certain furnaces. The presence of a secondary heat exchanger improves the AFUE of a consumer furnace but also increases internal static pressure. As a result, DOE expects that furnace fans used in condensing units will consume more electrical energy than similar, non-condensing units, and therefore use with condensing technology constitutes a performance-related feature for this product. Mobile home products meet certain design requirements that allow them to be installed in mobile homes. They require direct venting and are typically installed without return air ducting. As a result, furnace fans used in mobile home products consume a different amount of electric energy than furnace fans installed in similar HVAC products that are designed for site-built applications. Therefore, the ability to be installed in mobile home applications is a performance-related feature under EPCA.

Descriptors like gas, oil, or electric indicate the type of fuel that the HVAC product uses to produce heat, which determines the type and geometry of the primary heat exchanger used in the HVAC product. Each heat exchanger geometry could result in a unique internal static pressure and therefore, have differing impacts on furnace fan performance and energy consumption and are considered performance-related features.

In the July 2014 Final Rule, DOE created product classes for MH-NWO furnace fans and MH-WG furnace fans, but DOE did not analyze or prescribe standards for either product class because of the lack of available data for those product classes. 79 FR 38130, 38150. DOE is not aware of any products that would be considered MH-WG furnace fans at this time. However, DOE has become aware of a limited number of MH-NWO furnace fans that have been introduced to the market. The MH-NWO furnace fans that DOE identified are all used in non-condensing furnaces, so DOE analyzed a subset of the previously established but unanalyzed class—mobile home non-weatherized, oil, non-condensing (MH-NWO-NC) furnace fans. DOE specifically considered MH-NWO-NC furnace fans because, as with furnace fans used in gas-fired products, DOE tentatively concluded that suitability for use with condensing technology would be a performance related feature that would justify further separating MH-NWO furnace fans into condensing and non-condensing classes. Furnace fans used in oil-fired products that are non-condensing as compared to those that are condensing would have different performance due to likely differences in internal structure of condensing products (if any were to be developed). As such, suitability for use with condensing technology in a furnace fan is a performance-related feature under EPCA. As DOE is not aware of any condensing MH-NWO products, DOE did not analyze them for this NOPD analysis and instead focused on MH-NWO-NC furnace fans. In summary, DOE considered the product classes shown in the following list in its analysis.

(1) Non-weatherized, Non-condensing Gas Furnace Fan (NWG-NC)

(2) Non-weatherized, Condensing Gas Furnace Fan (NWG-C)

(3) Mobile Home Non-weatherized, Non-condensing Gas Furnace Fan (MH-NWG-NC)

(4) Mobile Home Non-weatherized, Condensing Gas Furnace (MH-NWG-C)

(5) Mobile Home Electric Furnace/Modular Blower Fan (MH-EF/MB)

(6) Non-weatherized, Non-condensing Oil Furnace Fan (NWO-NC)

(7) Weatherized Non-Condensing Gas Furnace Fan (WG-NC)

(8) Electric Furnace/Modular Blower (EF/MB)

(9) Mobile Home Non-Weatherized, Non-Condensing Oil Furnace Fan (MH-NWO-NC)

B. Engineering Analysis

The purpose of the engineering analysis is to establish the relationship between the efficiency and cost of consumer furnace fans. There are two elements to consider in the engineering

analysis; the selection of efficiency levels to analyze (
i.e.,
the “efficiency analysis”) and the determination of product cost at each efficiency level (
i.e.,
the “cost analysis”). In determining the performance of higher-efficiency products, DOE considers technologies and design option combinations not eliminated by the screening analysis. For each product class, DOE estimates the baseline cost, as well as the incremental cost for the product at efficiency levels above the baseline. The output of the engineering analysis is a set of manufacturer production costs (“MPCs”) in cost-efficiency “curves” that are used in downstream analyses (
i.e.,
the LCC and PBP analyses and the NIA).

1. Efficiency Analysis

DOE typically uses one of two approaches to develop energy efficiency levels for the engineering analysis: (1) relying on observed efficiency levels in the market (
i.e.,
the efficiency-level approach), or (2) determining the incremental efficiency improvements associated with incorporating specific design options to a baseline model (
i.e.,
the design-option approach). Using the efficiency-level approach, the efficiency levels established for the analysis are determined based on the market distribution of existing products (in other words, based on the range of efficiencies and efficiency level “clusters” that already exist on the market). Using the design option approach, the efficiency levels established for the analysis are determined through detailed engineering calculations and/or computer simulations of the efficiency improvements from implementing specific design options that have been identified in the technology assessment. DOE may also rely on a combination of these two approaches. For example, the efficiency-level approach (based on actual products on the market) may be extended using the design option approach to interpolate to define “gap fill” levels (to bridge large gaps between other identified efficiency levels) and/or to extrapolate to the “max-tech” level (particularly in cases where the “max tech” level exceeds the maximum efficiency level currently available on the market).

Although FER data exists in DOE's Compliance Certification Database (“CCD”) for furnace fans currently subject to efficiency standards, DOE has determined through testing that for many furnace fan models, the rated FER values may not be representative of the model's actual performance. During confidential manufacturer interviews, several manufacturers confirmed that they rate the FER of their furnace fan products conservatively. Therefore, an efficiency level approach was not possible because the FER ratings of products currently available are largely not representative of their actual performance. Thus, DOE chose a design option approach to identify efficiency levels for the analysis in this proposed determination.

a. Baseline Efficiency Level

For each product class, DOE generally selects a baseline model as a reference point for each class, and measures changes resulting from potential energy conservation standards against the baseline. The baseline model in each product class represents the characteristics of a product typical of that class (
e.g.,
capacity, physical size). Generally, a baseline model is one that just meets current energy conservation standards, or, if no standards are in place, the baseline is typically the most common or least efficient unit on the market. For consumer furnace fans, the energy conservation standard sets a maximum energy usage requirement and therefore a baseline furnace fan's rated FER is just below or at the maximum FER threshold.

DOE used baseline units for comparison in several analyses, including the engineering analysis, LCC analysis, PBP analysis, and NIA. To determine energy savings that will result from an amended energy conservation standard, DOE compared energy use at each of the higher efficiency levels to the energy consumption of the baseline unit. Similarly, to determine the changes in price to the consumer that will result from an amended energy conservation standard, DOE compared the prices of baseline units to the prices of units at each higher efficiency level.

The identification of baseline units requires establishing the baseline efficiency level. In cases where there is an existing standard, DOE defines baseline units as units with efficiencies equal to the current Federal energy conservation standards. For MH-NWO-NC furnace fan product class, which does not currently have energy conservation standards, DOE developed the baseline equation by modifying the current energy conservation standards for the NWO-NC product class to account for the lower ESP experienced by mobile home units compared to other units. Specifically, DOE multiplied the y-intercept (382) by 0.75, which was the conversion factor determined in the analysis for the July 2014 Final Rule that was previously used to calculate the MH-NWG-NC baseline based on the NWG-NC baseline.
8

8
Chapter 5 of the TSD accompanying the July 2014 Final Rule includes additional details about how this conversion factor was calculated.
See
docket no. EERE-2010-BT-STD-0011.

Table IV.2 presents the maximum FER (
i.e.,
the baseline level) for each product class of consumer furnaces analyzed in this preliminary analysis, as well as the typical characteristics of products at that level.

Table IV.2—Baseline Efficiency Level FER and Associated Design Option for Each Product Class

Product class
Maximum FER
Design option

Non-Weatherized, Non-Condensing Gas Furnace Fan

0.044 * Q
Max
+ 182

BPM Motor w/Forward Inclined Impeller.

Non-Weatherized, Condensing Gas Furnace Fan

0.044 * Q
Max
+ 195

BPM Motor w/Forward Inclined Impeller.

Weatherized, Non-Condensing Gas Furnace Fan

0.044 * Q
Max
+ 199

BPM Motor w/Forward Inclined Impeller.

Non-Weatherized, Non-Condensing Oil Furnace Fan

0.071 * Q
Max
+ 382

Improved PSC Motor w/Forward Inclined Impeller.

Non-Weatherized Electric Furnace Fan/Modular Blower Fan

0.044 * Q
Max
+ 165

BPM Motor w/Forward Inclined Impeller.

Manufactured Home, Non-Weatherized, Non-Condensing Gas Furnace Fan

0.071 * Q
Max
+ 222

Improved PSC Motor w/Forward Inclined Impeller.

Manufactured Home, Non-Weatherized, Condensing Gas Furnace Fan

0.071 * Q
Max
+ 240

Improved PSC Motor w/Forward Inclined Impeller.

Manufactured Home, Non-Weatherized Electric Furnace Fan/Modular Blower Fan

0.044 * Q
Max
+ 101

BPM Motor w/Forward Inclined Impeller.

Manufactured Home, Non-Weatherized Non-Condensing Oil Furnace Fan

0.071 * Q
Max
+ 287

Improved PSC Motor w/Forward Inclined Impeller.

Products in the NWG-NC, NWG-C, WG-NC, NWEF/NWMB, and MH-EF/MB products classes are currently subject to the standards set in the July 2014 Final Rule, in which the efficiency levels adopted were understood at that time to reflect models with CT-BPM motors and multi-stage operation. Products in the NWO-NC and MH-NWG-NC product classes are currently subject to the standards set in the July 2014 Final Rule in which the efficiency level adopted were understood to correspond to the performance associated with models including improved PSC motors and single-stage operation. Baseline products in the MH-NWO-NC product class were also found to correspond to performance associated with models including improved PSC motors and single-stage operation, based on DOE's market findings for mobile-home oil-fired units certified in DOE's CCD for consumer furnaces.

Many furnaces include multi-stage or modulating heating controls. However, based on current furnace fan market data as well as feedback received during manufacturer interviews, it is unclear if these features impact furnace fan efficiency as measured by FER (
see
section IV.A.2). Therefore, DOE did not include the costs of multi-stage or modulating heating controls in the baseline design (
i.e.,
DOE's MPC estimates reflect single-stage units). However, DOE did develop separate cost values for multi-stage or modulating heating controls that can be applied to the above costs to represent the addition of multi-stage or modulating heating controls (
see
section IV.B.2.b of this document). These additional cost values are used in DOE's LCC and PBP analyses in order to represent typical furnace fan cost distributions.

In addition, the baseline motor technology is either BPM or PSC, depending on the product class. Manufacturers may choose a CABPM motor instead of a CTBPM, despite its relatively higher cost, to add comfort utility to their product. This additional comfort may be marketed as a premium feature. Therefore, DOE included the cost of a CT-BPM motor in the MPCs for furnace fans with BPM motors. DOE also developed cost values to represent the cost increase for CA-BPM motors relative to CT-BPM motors (
see
section IV.B.2.b of this document). These values were applied in the LCC analysis to represent the distribution of BPM blower motor technologies expected on the market because, although DOE is not differentiating between CA-BPM motors and CT-BPM motors in terms of furnace fan efficiency, manufacturers and consumers may consider CA-BPM motors to be a premium feature that may offer comfort-related consumer utility benefits.

In developing the cost-efficiency relationship, teardowns of baseline units were used as a reference point for determining the cost-efficiency relationship of units with lower (more efficient) FERs. DOE compared the design features incorporated into products at the baseline efficiency to the features of units with higher energy efficiencies in order to determine the changes in manufacturing, installation, and operating costs that occur as FER decreases.

In response to the November 2022 Preliminary Analysis, Morrison commented that DOE's estimation of FER values is conservative, based on data from OEMs and DOE, both of which indicate that analysis from 2014 is not representative of current furnace fan function and composition. (Morrison, No. 27 at p. 2) Lennox commented that the use of BPM motors is required to meet current furnace fan efficiency standards for most consumer furnace fan categories and use of BPM motors is identified by DOE as the current baseline. (Lennox, No. 24 at p. 8)

AHRI commented that baseline mobile home non-weatherized gas furnace fan technology is not representative of the market. AHRI stated that, in many cases, the current FER rating for mobile home non-weatherized gas furnace fans cannot be met using a PSC motor, adding that these products already incorporate a BPM motor to meet Federal minimum standards. AHRI added that because mobile home non-weatherized gas furnace fans already incorporate BPM motors to meet the current levels, BPM motors will not be able to meet the FER minimums proposed at EL 1. (AHRI, No. 23 at p. 3) AHRI recommended that DOE validate the analysis performed for mobile home non-weatherized gas furnace fan to ensure the baseline and subsequent ELs are correct. (
Id.
)

The Joint Commenters stated that current standards for both weatherized and non-weatherized non-condensing gas furnace fans were intended to effectively require use of efficient BPM motors, but stated that DOE's analysis shows some non-condensing gas furnace fans utilizing PSC motors can meet the current standards. The Joint Commenters noted that one currently available furnace/furnace fan model utilizes a PSC motor and is marketed as having a small footprint and DOE should investigate how this model and others are able to meet the current standards with presumably less efficient motors. (Joint Commenters, No. 20 at p. 2)

The CA IOUs commented that they agree with DOE's decision to use the costs associated with constant-torque BPM and single-stage controls for its cost analysis for EL 1, adding that DOE has found several furnace fans on the market that meet EL 1. (CA IOUs, No. 21 at p. 2) The CA IOUs also noted that a 2017 California Codes and Standards Enhancement report evaluated air handlers sold with heat pumps and confirmed that while cabinet and blower design can affect internal resistance to airflow, a PSC motor can adversely affect fan efficacy. (
Id.
at p. 5)

In response, DOE notes that it has developed baseline efficiency levels that are representative of the baseline technologies used in the current furnace fan market. While the FER ratings reported in CCMS are generally likely to be conservative estimates, DOE has conducted testing to understand the impacts of the technology options identified in section IV.A.2 on furnace fan efficiency, and has developed efficiency levels that reflect those impacts. DOE agrees with commenters that the use of BPM motors is necessary to meet the baseline for some product classes, as outlined in Table IV.2, but notes that some product classes can meet the baseline efficiency level using an improved PSC motor. In response to AHRI's comments, although DOE recognizes that many mobile home

furnaces use BPM motors, DOE is aware of mobile home furnaces on the market that use an improved PSC motor and meet the current FER standards. DOE thus concludes that FER standards can be achieved using this technology and has maintained improved PSC motors as a part of the baseline design option for mobile home furnaces. Conversely, DOE's market data shows that no non-weatherized gas furnaces currently on the market use PSC motors; DOE therefore concludes that a BPM motor continues to be an appropriate baseline motor design for this class.

b. Intermediate Efficiency Levels

DOE analyzed intermediate efficiency levels for NWO-NC, MH-NWG-NC, MH-NWG-C, and MH-NWO-NC classes of consumer furnace fans. As discussed in section IV.B.1.c, DOE did not identify any efficiency levels between baseline and max-tech for the NWG-NC, NWG-C, WG-NC, NWEF/NWMB, and MH-EF/MB classes. The intermediate efficiency levels identified are representative of efficiency levels where major technological changes occur (
i.e.,
replacing PSC motors with BPM motors). As discussed in section IV.B.1.a of this document, DOE has tentatively found that CT-BPM motors and CA-BPM motors have comparable impacts on FER ratings, and DOE has therefore only analyzed a single efficiency level reflecting the implementation of BPM motors. Additionally, DOE has tentatively used the assumption of a 12-percent reduction in FER for improved PSC motors and a 46-percent reduction in FER for models with a CT-BPM and multi-staging from the baseline used in the 2014 Final Rule (79 FR 38130, 38159) to calculate a 39-percent reduction in FER from improved PSC (the current baseline) to CT-BPM with multi-staging. The 39-percent reduction in FER is implemented into the current analysis to represent the reduction in FER from improved PSC to a model with a CT-BPM (regardless of staging) because DOE has tentatively decided not to include staging as a technology option that improves FER.

In response to the November 2022 Preliminary Analysis, Lennox commented that the efficiency levels and design options associated with the use of forward curved impellers and BPM motors are reasonable. (Lennox, No. 24 at p. 7)

The Joint Commenters commented that models with lower FERs than EL 1 are available in each of the major furnace fan product classes. The Joint Commenters commented that, based on results in the CCD, both condensing and non-condensing non-weatherized furnace fans with efficiencies exceeding EL 1 are available across a broad range of airflows. The Joint Commenters stated that, as DOE acknowledged in the TSD, many manufacturers rate their furnace fans conservatively, which suggests the number of higher-efficiency furnace fans available on the market is understated. (Joint Commenters, No. 20 at pp. 1-2) Additionally, the Joint Commenters encouraged DOE to analyze an EL associated with improved BPM motor efficiency. The Joint Commenters stated that a range of BPM motor efficiencies currently exist on the market but added that DOE did not analyze improved motor efficiency as a potential design option. The Joint Commenters encouraged DOE to gather additional information from motor manufacturers to characterize the FER reductions achievable with the most efficient BPM motors available, and to analyze an EL associated with these higher efficiency BPM motors for the next stage of the rulemaking. (
Id.
at p. 3)

DOE is not aware of any data showing the relationship between improved motor efficiency and FER ratings. DOE welcomes data exploring this relationship and may include efficiency levels corresponding to the use of more efficient BPM motors in a future analysis but did not include this additional efficiency level in the current analysis due to the lack of data.

c. Maximum Technology Efficiency Levels

As part of DOE's analysis, the maximum available efficiency level is the highest efficiency unit currently available on the market. DOE also defines a “max-tech” efficiency level to represent the maximum possible efficiency for a given product. DOE identified the max-tech design for all consumer furnace fans product types as incorporating a BPM motor with a backward-inclined impeller.

BPM motors are described in sections IV.B.1.a and IV.B.1.b of this chapter. For furnace fan models that use PSC motors, BPM motors can offer an improvement in efficiency and reduce FER. Backward-inclined impellers, in comparison to forward-inclined impellers used in the majority of furnace fans on the market, have been found to have a higher efficiency under certain operating conditions. In chapter 5 of the TSD accompanying the November 2022 Preliminary Analysis, DOE explained that it has tentatively used the same assumptions about the percent reduction in FER associated with implementing backward-inclined impellers as in the July 2014 Final Rule (
i.e.,
a 10-percent reduction in FER compared to models that include forward-inclined impellers). 79 FR 38130, 38159.

In response to the November 2022 Preliminary Analysis, several commenters raised concerns about the assumption that a backward-inclined impellers will reduce FER by 10 percent. Several commenters suggested that the impact of backward-inclined impellers on FER may vary by application. Carrier commented that DOE correctly concluded in the TSD that the efficiency improvement of a backward-inclined impeller is not uniform across the entire range of operation. Carrier stated that this lack of uniformity can require limiting the operating range, which reduces the furnace utility, or leads to unrealized efficiency improvements in application. Carrier stated that it believes backward-inclined impellers are not a technologically feasible design option in some models because they do not improve efficiency and in other models they reduce furnace utility. Carrier stated that its non-weatherized 95-percent-plus AFUE 14-inch-width gas furnaces use backward-inclined impellers to meet the current FER standards. (Carrier, No. 19 at pp. 3-4) Carrier commented that it completed extensive research and evaluated the impact of this technology in many furnace variations and suggested that DOE's technology assessment does not fully account for the design challenges of using backward-inclined impellers in consumer furnaces. Carrier commented that the improvement in fan efficiency is not uniform across model sizes within a product family due to design changes needed to address the safety and reliability
9

of the furnaces. Carrier requested that DOE continue its study of backward-inclined impeller technology to better understand the efficiency improvement variation across product sizes before concluding a uniform reduction in FER for a product class. Carrier also stated that because its models that incorporate backward-inclined impeller use the maximum technology design options, any reduction in the FER limit would eliminate them from the market. (
Id.
at pp. 1-3)

9
Carrier's comments related to safety and reliability concerns are discussed in section IV.A.4.a of this document.

AHRI commented that it is aware of products on the market which use proprietary backward-inclined impeller designs that are not capable of meeting the FER that DOE has associated with

that design option. AHRI further commented that these products are some of the highest-efficiency products on the market and stated that if the FER requirement is moved to a max-tech level, both furnace fan availability and high-efficiency furnace availability will be affected. (AHRI, No. 23 at pp. 5-6)

The CA IOUs requested that DOE conduct additional research on backward-inclined fan performance to ensure the projected energy savings. The CA IOUs further requested that DOE collect current data on the performance of backward-inclined impellers in furnaces to compare with forward-curved fans available in 2023. The CA IOUs commented that DOE's calculations appeared to be based on research that may not reflect the current performance of forward-curved fans and instead overstates the performance of backward-inclined fans on the market. The CA IOUs commented that DOE's findings of 10-percent energy savings expected from backward-inclined fans were first presented in the 2014 TSD and were based on 2003 GE testing of a single backward-inclined prototype against a single forward curved fan. The CA IOUs commented that a follow-up LBNL report found that the construction of the forward-curved fan tested in 2003 was substandard and contained large gaps between the impeller and housing and misalignment between the impeller and inlet. The CA IOUs pointed out that furnace fans in 2003 had no performance requirements and that with the advent of furnace fan regulation, forward-curved fan design has improved while backward-inclined fans currently available are not noticeably better than the prototype tested in 2003. The CA IOUs presented data showing the performance of one manufacturer's forward-curved and backward-inclined fans and commented that additional research is needed to confirm the efficiency difference before DOE considers using backward-inclined fans. (CA IOUs, No. 21 at pp. 2-5)

Morrison stated that the GE fan referenced by DOE (as the basis of the backward inclined impeller analysis) was used in LBNL research and had limited benefit when compared to a forward-curved fan. Furthermore, Morrison commented that more information was needed regarding claims in the TSD that the use of EBM fans resulted in a 15-30-percent improvement. Morrison stated that DOE used an estimated 10-percent FER improvement from the 2014 rulemaking, but that would be relative to older designs made prior to changes seen in furnace fans since 2019. Morrison stated that consumer furnace fans have been improved since then to improve energy use. (Morrison, No. 27 at p. 2) No commenters submitted data supporting an alternative FER reduction value to associate with backward-inclined impellers. Therefore, DOE continued to rely on the best data available, which is what DOE used to arrive at the assumption that backward-inclined impellers uniformly reduce the FER of consumer furnace fans by a 10-percent reduction in the July 2014 Final Rule. With respect to Morrison's comments that the furnace fan designs have changed since 2014, DOE notes that the estimate of a 10-percent reduction is not relative to the baseline design, but instead is relative to an equivalent furnace fan with a forward curved impeller and thus still applies. In other words, in the July 2014 Final Rule, DOE estimated that implementing a backward-inclined impeller in place of a forward-inclined impeller would reduce FER by 10 percent in a furnace fan with a constant-airflow BPM motor and multi-staging; it was not relative to a baseline furnace with a PSC motor and single-stage operation. 79 FR 38130, 38159. (As previously discussed, for this analysis DOE did not find evidence of significant differentiation in FER among multi-stage models as compared to single-stage models, or between constant-airflow and constant-torque BPM motors.) However, the concerns and uncertainties raised by commenters in the above paragraphs contribute to DOE's tentative decision not to adopt standards at max-tech levels for furnace fans at this time. For additional discussion regarding backward-inclined impellers,
see
section IV.H of this document.

In response to DOE's consideration of backward-inclined impellers at the max-tech level in the November 2022 Preliminary Analysis, commenters discussed a number of concerns with implementing the technology.

AHRI commented that there is no one-size-fits-all design for incorporating backward-inclined impellers into current products. AHRI stated that changes in the airflow design will require redesign and retesting on a model-by-model basis to ensure both proper operation and compliance with safety standards. (AHRI, No. 23 at p. 5) AHRI commented that the issues associated with moving from a forward-inclined impeller to a backward-inclined impeller will require safety testing and redesign. AHRI further commented that these additional costs are not accounted for in the analysis. (
Id.
at p. 3)

Trane commented that, based on its research, a backward-inclined impeller is not compatible with current furnace dimensions, which are not large enough to accommodate a backward-inclined impeller. Trane added that it cannot be assumed that furnace design changes will have no impact on energy use and equipment utility when a backward-inclined impeller is used in the existing housing. Furthermore, Trane commented that, based on its research, the issues of the inlet cone design and clearances to the moving impeller remain a concern and require attention. (Trane, No. 22 at p. 2)

Trane commented that adopting EL 1 would require replacing the current forward-inclined impeller with a backward-inclined impeller. Trane added that its research showed a 7-year development cycle for the blower system technology needed to adopt EL 1. Trane commented that this same research surfaced concerns with the ability to manufacture a high-speed (~1800 RPM max) blower wheel with close tolerances with the inlet cones, and significant leakage of high-pressure air from the exhaust portion of the housing back into the low-pressure input region if typical 0.25-in gaps are implemented. Trane commented that improvements from only retrofitting the impeller were less than 10 percent unless blower housing modifications were made. Trane commented that its determination regarding the impellers was based on a study completed more than 20 years ago, “Final Report for the Variable Speed Integrated Intelligent HVAC Blower, Final Report for BP-2” (June 1, 2003). (Trane, No. 22 at p. 2)

Trane acknowledged that DOE's findings were based on the EBM-Papst furnace model, which has a backward-inclined impeller blower system. Trane commented that the EBM-Papst system is not an impeller change, but a different blower system that produces a different air flow pattern from the forward-inclined impeller and is thus not able to be tested according to the same standards as a furnace fan with a forward-inclined impeller. Trane commented that for all manufacturers to adopt this system would require all safety, performance, and AFUE testing to be performed in order to put it into production, and furthermore, due to its need for an inlet orifice, this system limits the furnace's return air location to a single location (
i.e.,
left side, right side, or bottom). Trane added that higher air flow furnaces often need more than a single side return to perform properly for CFM and watts, and therefore adopting the EBM-Papst approach would not be possible for many furnace fan manufacturers. Trane commented that, for the reasons stated

above and because it would reduce the utility of the furnace, the EBM-Papst system is unsuitable as a basis for comparison for adopting EL 1 among furnace fan manufacturers. (
Id.
) Furthermore, Trane commented that adapting all furnace fans to accommodate the EBM-Papst system would reduce the utility of the furnace and increase the installation time needed to move components to reach the return air location required by the system. Trane commented that the EBM-Papst system should have been analyzed as a separate EL level. (Trane, No. 22 at pp. 2-3)

Trane commented that testing would be required ahead of introducing the impeller change in order to determine the effects this difference would have on heat exchanger temperatures, furnace efficiency, and safety limit operation. Trane commented that according to DOE, housing design modifications were eliminated from consideration due to the resulting reduction in utility that such a change produces. Trane commented that the same logic should apply to an impeller change that creates a substantially different discharge velocity distribution. (Trane, No. 22 at p. 3)

Lennox commented that the application of backward-inclined impellers would require changes in the housing design and airflow patterns that DOE has already screened out in the TSD. Lennox further commented that changes in the airflow design will require redesign and retesting on a model-by-model basis to ensure proper operation, compliance with safety standards, and product reliability. (Lennox, No. 24 at p. 7)

AHRI commented that backward-inclined impellers require a larger diameter than the forward-inclined impellers they are intended to replace, stating that backward-inclined impellers will not fit in the cabinet of a fan with a forward-inclined impeller. They further commented that most all models will have to be redesigned to accommodate the larger impeller, adding that it will lead to housing design and airflow path modifications. AHRI stated DOE has acknowledged that modifications of housing design and airflow path have an adverse impact on furnace efficiency. (AHRI, No. 23 at p. 3)

AHRI commented that furnace cabinets are limited in size due to the dimensions of the installation space. AHRI stated that smaller-sized furnaces are at a disadvantage when it comes to meeting the required FER level because of the relationship between the furnace input level and the width of the furnace. AHRI commented that a change to the efficiency level to include backward-inclined impellers, coupled with the proposed future change to the minimum AFUE, would likely eliminate the smallest cabinet sizes from the marketplace without replacement furnace options or with reduced choices for consumers in cases where the smallest size model is required. (AHRI, No. 23 at p. 6)

The CA IOUs suggested that DOE refrain from implementing energy conservation standards that would require the use of backward inclined fans, as the CA IOUs could not identify furnaces incorporating backward-inclined fans available for purchase. (CA IOUs, No. 21 at p. 2)

In response, as discussed previously and as several commenters acknowledge, DOE is aware of backward-inclined impellers being used in other sectors of the HVAC industry and also in a small number of consumer furnace fan models available today. Therefore, DOE has found this design option to be technologically feasible. DOE identified and examined the models that currently use backward inclined impellers and did not identify any significant differences in cabinet dimensions, overall construction, or any indication of installation constraints as compared to similar models using a forward-curved impeller. As a result, DOE maintained backward-inclined impellers as a design option at max-tech for this analysis. However, given the limited number of consumer furnace fan models that this technology is currently used in, DOE recognizes that there are some uncertainties with applying it to the entire consumer furnace fans market and across the entire range of capacities, as pointed out by several commenters. As discussed in section V.C of this document, DOE is proposing not to amend standards and therefore use of a backward inclined impeller would not be required. While this decision is primarily based on the cost effectiveness of this design option at this time, DOE has also considered some analytical uncertainties, as discussed in sections IV.H and V.C of this document.

d. Summary of Efficiency Levels Analyzed

The efficiency levels and associated technologies analyzed for each class of consumer furnace fan are shown in Table IV.3 through Table IV.11.

Table IV.3—Efficiency Levels and Technologies Used at Each Efficiency Level for NWG-NC Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.044 * Q
Max
+ 182

BPM Motor w/Forward-Curved Impeller
N/A

1—Max-tech

0.04 * Q
Max
+ 164

BPM Motor w/Backward-Inclined Impeller
10

Table IV.4—Efficiency Levels and Technologies Used at Each Efficiency Level for NWG-C Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.044 * Q
Max
+ 195

BPM Motor w/Forward-Curved Impeller
N/A

1—Max-tech

0.04 * Q
Max
+ 176

BPM Motor w/Backward-Inclined Impeller
10

Table IV.5—Efficiency Levels and Technologies Used at Each Efficiency Level for WG-NC Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.044 * Q
Max
+ 199

BPM Motor w/Forward-Curved Impeller
N/A

1—Max-tech

0.04 * Q
Max
+ 179

BPM Motor w/Backward-Inclined Impeller
10

Table IV.6—Efficiency Levels and Technologies Used at Each Efficiency Level for NWEF/NWMB Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.044 * Q
Max
+ 165

BPM Motor w/Forward-Curved Impeller
N/A

1—Max-tech

0.04 * Q
Max
+ 149

BPM Motor w/Backward-Inclined Impeller
10

Table IV.7—Efficiency Levels and Technologies Used at Each Efficiency Level for MH-EF/MB Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.044 * Q
Max
+ 101

BPM Motor w/Forward-Curved Impeller
N/A

1—Max—Tech

0.04 * Q
Max
+ 91

BPM Motor w/Backward-Inclined Impeller
10

Table IV.8—Efficiency Levels and Technologies Used at Each Efficiency Level for MH-NWG-NC Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.071 * Q
Max
+ 222

Improved PSC Motor
N/A

1

0.044 * Q
Max
+ 137

BPM Motor w/Forward-Curved Impeller
39

2—Max-tech

0.04 * Q
Max
+ 123

BPM Motor w/Backward-Inclined Impeller
45

Table IV.9—Efficiency Levels and Technologies Used at Each Efficiency Level for MH-NWG-C Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.071 * Q
Max
+ 240

Improved PSC Motor
N/A

1

0.044 * Q
Max
+ 148

BPM Motor w/Forward-Curved Impeller
39

2—Max-tech

0.04 * Q
Max
+ 133

BPM Motor w/Backward-Inclined Impeller
45

Table IV.10—Efficiency Levels and Technologies Used at Each Efficiency Level for NWO-NC Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.071 * Q
Max
+ 382

Improved PSC Motor
N/A

1

0.044 * Q
Max
+ 236

BPM Motor w/Forward -Curved Impeller
39

2—Max-tech

0.04 * Q
Max
+ 212

BPM Motor w/Backward-Inclined Impeller
45

Table IV.11—Efficiency Levels and Technologies Used at Each Efficiency Level MH-NWO-NC Fans

EL
FER equation
Description of technologies typically incorporated

Percent
reduction in
FER from
baseline

0—Baseline

0.071 * Q
Max
+ 287

Improved PSC Motor
N/A

1

0.044 * Q
Max
+ 176

BPM Motor w/Forward -Curved Impeller
39

2—Max-tech

0.04 * Q
Max
+ 158

BPM Motor w/Backward-Inclined Impeller
45

2. Cost Analysis

The cost analysis portion of the Engineering Analysis is conducted using one or a combination of cost approaches. The selection of cost approach depends on a suite of factors, including the availability and reliability of public information, characteristics of the regulated product and the availability and timeliness of purchasing the consumer furnace fans on the market. The cost approaches are summarized as follows:

•
Physical teardowns:
Under this approach, DOE physically dismantles a commercially available product, component-by-component, to develop a detailed bill of materials for the product.

•
Catalog teardowns:
In lieu of physically deconstructing a product, DOE identifies each component using parts diagrams (available from manufacturer websites or appliance repair websites, for example) to develop the bill of materials for the product.

•
Price surveys:
If neither a physical nor catalog teardown is feasible (for example, for tightly integrated products such as fluorescent lamps, which are infeasible to disassemble and for which parts diagrams are unavailable) or cost-prohibitive and otherwise impractical (
e.g.,
large commercial boilers), DOE conducts price surveys using publicly available pricing data published on major online retailer websites and/or by soliciting prices from distributors and other commercial channels.

In the present case, DOE conducted its cost analysis using a combination of physical and catalog teardowns to assess how manufacturing costs change with increased product efficiency. DOE estimated the MPC associated with each efficiency level to characterize the cost-efficiency relationship of improving consumer furnace fan performance. The MPC estimates are not for the entire HVAC product. Because consumer furnace fans are a component of the HVAC product in which they are integrated, the MPC estimates include costs only for the components of the HVAC product that impact FER.

Products were selected for physical teardown analysis that have characteristics of typical products on the market at a representative input capacity of 80,000 Btu/h for the NWG-NC, NWG-C, WG-NC, NWEF/NWMB, MH-NWG-NC, MH-NWG-C, MH-EF/MB, and MH-WG product classes and 105,000 Btu/h for the NWO-NC and MH-NWO product classes (determined based on market data and discussions with manufacturers). Selections spanned a range of FER efficiency levels and designs and included most manufacturers. The resulting bill of materials provides the basis for the manufacturer production cost (“MPC”) estimates.

To account for manufacturers' non-production costs and profit margin, DOE applies a multiplier (the manufacturer markup) to the MPC. The resulting manufacturer selling price (“MSP”) is the price at which the manufacturer distributes a unit into commerce. DOE developed an average manufacturer markup by examining the annual Securities and Exchange Commission (“SEC”) 10-K reports filed by publicly-traded manufacturers primarily engaged in HVAC manufacturing and whose combined product range includes consumer furnace fans. DOE refined its understanding of manufacturer mark-ups by using information obtained during manufactur

[Text truncated at 120,000 characters. The full text is on the page linked above.]

---

Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2023-22149. Public record. Not legal advice.