EPA’s Technology Transitions Program Related to A2L Refrigerants (Q4 2025 Update)
Our experts address persisting questions within the HVAC industry and building code enforcement world with regards to the HFC refrigerant phasedown and the subsequent transition to A2L refrigerants.
The end of another year is quickly approaching, and questions persist within the HVAC industry and building code enforcement world with regards to the HFC refrigerant phasedown and the subsequent transition to A2L refrigerants. To summarize, over the past four years, the Environmental Protection Agency (EPA) has enacted two programs impacting these industries.
The first program, the HFC Phasedown Program, is like the refrigerant phasedown/phaseout programs of the past – phasing down the use of a particular refrigerant over a prolonged length of time (15 years for the HFC phasedown).
The second program, the Technology Transitions Program, impacts residential and light commercial construction projects across the U.S.

Current EPA Regulations
The Technology Transitions Program was implemented to support the HFC phasedown by forcing a transition to next-generation equipment that does not utilize HFC refrigerants. The final rules placed restrictions on both the manufacture and installation of HVAC products and systems beginning on Jan. 1, 2025. The regulations for residential and light commercial air conditioning and heat pump systems as they currently stand:
- prohibit the manufacture of HVAC system components “for use in a NEW HVAC system” on or after Jan. 1, 2025; and
- prohibit the installation of new HVAC systems with GWPs >700 on or after Jan. 1, 2026.
Note that under these rules, the “installation of a system” means that all system components have been field-assembled, fully charged with refrigerant and the system can function and is ready for use for its intended purpose.
Industry Challenges
HVAC equipment manufacturers, distributors, dealers and building officials have been preparing for the transition to A2Ls over the course of the year, however, supply chain issues have interfered with the rollout of the new air-conditioning equipment and refrigerants. The industry has been experiencing a shortage of R454B refrigerant, but more importantly it has been dealing with a shortage of the A2L refrigerant cylinders.
Shortages of 20-lb cylinders for A2L refrigerants have affected the availability of these refrigerants for HVAC installers and service contractors. This is important because these cylinders are required to properly charge the HVAC systems. Without an A2L refrigerant cylinder to carry and transport the refrigerant, the contractors can’t complete this important installation step.
In some areas, this has contributed to the hoarding of A2L refrigerants that may have resulted in regional shortages, and in some cases, resulted in higher installation costs and long lead times for consumers needing new air conditioning systems. As a result, contractors are looking for alternative solutions like installing equivalent HFC systems in lieu of A2L systems, where feasible – unfortunately, the Dec. 31, 2025, deadline for the installation of HFC systems is quickly approaching.
In response to the supply chain issues and the growing concerns about A2L refrigerant availability and affordability, the EPA has issued a proposed rule reconsidering certain regulations under the Technology Transitions Program.
With respect to residential and light commercial air conditioning and heat pump systems, they have proposed removing the installation compliance date for these systems.
Proposed EPA Regulations
On Sept. 30, 2025, the EPA published a proposed rule for public comment titled “Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory Requirements Promulgated Under the Technology Transitions Provisions of the American Innovation and Manufacturing Act of 2020.”
The proposed rule removes the language prohibiting the installation of new HVAC systems with GWPs >700 on or after Jan. 1, 2026, and replacing it with the language:
“New residential and light commercial air-conditioning and heat pump systems using a regulated substance, or a blend containing a regulated substance, with a global warming potential of 700 or greater may continue to be installed where all specified components of that system are manufactured or imported prior to Jan. 1, 2025.”
Removing the installation compliance date would allow industry to sell through any remaining inventory of R410A equipment that was manufactured or imported prior to Jan. 1, 2025. However, this would not permit the installation of new systems using any components manufactured or imported on or after Jan. 1, 2025.
A2L Refrigerants Transition Resources
To further assist industry professionals in their efforts to safely transition to A2L refrigerants, the Code Council has developed the A2L refrigerant “Hot Topics” page which can be found on our website here.
Titled “Preparing for A2L Refrigerants,” this page offers a collection of videos from the Code Council and industry partners. These videos cover various aspects of the transition to A2L refrigerants that are important for building officials, contractors, technicians and other industry professionals. Additionally, the page includes links to other valuable resources related to A2L refrigerants.
To access any of the Code Council’s PMG-related resources, click here. To subscribe to the PMG newsletter, click here.
For further details regarding the outcome of this proposed rule, please refer to the links below. They will take you to the relevant EPA, Federal Register and Code of Federal Regulations websites and documents for further information.
EPA Website Links:
- Regulatory Actions for Technology Transitions
- Technology Transitions Reconsideration Rule Fact Sheet (pdf)
- Technology Transitions Reconsideration Rule Summary (pdf)
- HFCs and the AIM Act Protecting Our Climate by Reducing Use of HFCs
- Frequent Questions on the Phasedown of Hydrofluorocarbons
- EPA Technology Transitions Program
Federal Register Links:
- Proposed Rule (10/03/2025) – Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory Requirements Promulgated Under the Technology Transitions Provisions of the American Innovation and Manufacturing Act of 2020
- Interim Final Rule (12/26/2023) – Phasedown of Hydrofluorocarbons: Technology Transitions Program Residential and Light Commercial Air Conditioning and Heat Pump Subsector
- Final Rule (10/24/2023) – Phasedown of Hydrofluorocarbons: Restrictions on the Use of Certain Hydrofluorocarbons Under the American Innovation and Manufacturing Act of 2020


