On July 2, 2026, U.S. Secretary of Energy Chris Wright announced a Notice of Proposed Rulemaking (NOPR) to overhaul the so-called "Process Rule" — the procedural framework that governs how DOE sets and revises energy-efficiency standards for consumer products, including central air conditioners, heat pumps, furnaces, and boilers ([DOE](https://www.energy.gov/articles/trump-administration-moves-permanently-end-green-new-scam-appliance-mandates)). The comment deadline is August 6, 2026, with a public webinar held July 15 ([DOE Process Rule](https://www.energy.gov/cmei/buildings/process-rule)).
For anyone buying or installing HVAC equipment, the Process Rule matters because it determines how aggressively DOE pushes efficiency minimums — and how much evidence the agency needs before raising the bar. Here's what's on the table.
What the Process Rule actually does
The Process Rule, formally at 10 CFR 430 Appendix A to Subpart C, has existed since 1996. It describes the procedures, interpretations, and policies DOE follows when establishing new or revised energy-conservation standards for covered products. That includes the analytical methods, the economic tests, and the threshold for whether amended standards are justified ([DOE Process Rule](https://www.energy.gov/cmei/buildings/process-rule)).
In practice, the Process Rule shapes every efficiency number that ends up on an equipment spec sheet — SEER2 minimums for central ACs, AFUE for furnaces, HSPF2 for heat pumps, UEF for water heaters. When DOE decides whether to raise those numbers, the Process Rule governs how that decision is made.
What the NOPR would change
The proposed rulemaking would make several significant changes to the Process Rule ([DOE Process Rule](https://www.energy.gov/cmei/buildings/process-rule)):
| Provision | Current | Proposed |
|---|---|---|
| Binding on DOE | Guidance (partially binding) | Binding for certain actions |
| Energy savings threshold | No fixed definition | New "significant energy savings" definition |
| Economic thresholds | Limited | Specific economic thresholds added |
| Comparative analysis | Not required | "Walk up" approach reinstated |
| Evidence standard | Modified from 2020 | "Clear and convincing evidence" reinstated |
| Base text | 2021/2024 revisions | Reverts to 2020 Process Rule text |
What "clear and convincing evidence" means.This is a higher legal bar than the standard used in recent rulemakings. If adopted, DOE would need stronger evidence that a new standard saves a significant amount of energy and is economically justified before it can be finalized. In practice, this could slow or block future efficiency increases for HVAC equipment.
The furnace standard — still in play
Separate from the Process Rule, the consumer furnace standard from DOE's December 2023 final rule remains active. That rule requires non-weatherized gas furnaces to meet 95% AFUE, with a compliance date of December 18, 2028 ([DOE Consumer Furnaces](https://www.energy.gov/cmei/buildings/consumer-furnaces)). In February 2026, the American Gas Association, American Public Gas Association, and National Propane Gas Association petitioned DOE to amend the compliance dates for both commercial water heating equipment and consumer furnaces. DOE sought public comment on that petition through May 27, 2026.
For homeowners with older 80% AFUE furnaces, the 95% standard doesn't force replacement of existing equipment — it applies to new manufactured units after the compliance date. But it does mean that when the time comes, the replacement will be a condensing furnace, which requires different venting.
Current HVAC efficiency minimums (in effect now)
Regardless of what the Process Rule NOPR changes, the standards already on the books remain enforceable. Here are the current residential minimums under SEER2 ([DOE FEMP](https://www.energy.gov/cmei/femp/incorporate-minimum-efficiency-requirements-heating-and-cooling-products-federal)):
- Central AC (split, <65,000 Btu/h): 15.0 SEER2 / 12.5 EER2 (single-phase); 14.0 SEER2 (three-phase)
- Heat pump (split, <65,000 Btu/h): 15.0 SEER2 / 8.5 HSPF2 (single-phase)
- Gas furnace (non-weatherized): 80% AFUE (current); 95% AFUE effective Dec 2028
- Gas boiler (hot water, <300,000 Btu/h): 90% AFUE
The tax credit angle
Homeowners installing qualifying high-efficiency equipment can still claim the Section 25C federal tax credit — 30% of project cost up to $2,000 annually for heat pumps and biomass stoves, and up to $1,200 for other qualified energy improvements including central ACs, furnaces, and boilers. The credit was established under the Inflation Reduction Act and applies to equipment placed in service through 2025 ([IRS](https://www.irs.gov/credits-deductions/home-energy-tax-credits)). Whether Congress extends or modifies the credit beyond 2025 remains an open question as of mid-2026.
Why this matters for your next HVAC decision
If the Process Rule NOPR is finalized, future efficiency increases for HVAC equipment would face a higher evidentiary bar and additional economic thresholds. That doesn't roll back existing standards — your 15.0 SEER2 AC and 95% AFUE furnace rule are still in force — but it could slow the pace of new rulemakings for the next round of increases.
For homeowners, the practical takeaway: equipment you buy today meets current federal minimums, and the 2023 SEER2 transition is settled. The open question is what the next round of increases looks like and when it arrives. The comment period is your chance to weigh in — comments can be submitted via Regulations.gov under docket EERE-2025-BT-STD-0001 ([DOE Process Rule](https://www.energy.gov/cmei/buildings/process-rule)).
Not an endorsement.Naming specific regulations, standards, or agencies does not constitute a position on any policy. HVAC Zone Inc is brand-neutral and does not advocate for or against any regulatory outcome. This article is informational only.
The bottom line
The Process Rule NOPR would make it harder — not impossible — for DOE to raise HVAC efficiency standards in future rulemakings, by adding economic thresholds and reinstating a "clear and convincing evidence" standard. Existing standards, including SEER2 minimums and the 2028 furnace AFUE increase, remain in effect. The comment deadline is August 6, 2026.
Trying to figure out what efficiency tier makes sense for your home or building? Request a consultation — we'll evaluate your system, your ductwork, and your actual load, not just a spec sheet.