The Short History: Why Refrigerants Keep Changing
If you have been in the chiller industry for more than a decade, you have already lived through one major refrigerant transition. Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) — including the once-ubiquitous R-22 — were phased out because they destroy the ozone layer. The industry moved to hydrofluorocarbons (HFCs) like R-410A as the safe alternative.
The problem is that HFCs, while ozone-safe, turned out to be extraordinarily potent greenhouse gases. R-410A has a Global Warming Potential (GWP) of 2,088 — meaning one pound of it released into the atmosphere has the same climate impact as 2,088 pounds of carbon dioxide. That is not a rounding error.
The result is a second major transition, now underway, driven by the American Innovation and Manufacturing (AIM) Act and the EPA rules that implement it.
What the AIM Act Actually Does
The AIM Act, signed into law in December 2020, gave the EPA authority to phase down HFC production and consumption in the United States. The EPA used that authority to create the Technology Transitions Rule, which restricts the use of high-GWP refrigerants in specific equipment categories going forward.
The practical effect for most commercial chiller applications: new equipment must use refrigerants with a GWP at or below approximately 700 beginning in 2025.
What this means in practice: R-410A (GWP 2,088) cannot be used in most new comfort-cooling and process-chilling equipment manufactured after the compliance date. Equipment already installed and operating is not immediately affected — but new units must use compliant refrigerants.
Primary source: 40 CFR Part 84 Subpart G — EPA Technology Transitions Program
The Replacement Refrigerants: R-454B and R-32
The two refrigerants that have emerged as the primary R-410A replacements in commercial cooling equipment are R-454B (GWP 466) and R-32 (GWP 675). Both fall comfortably below the 700-GWP threshold. Both also perform similarly to R-410A in terms of efficiency and operating pressures, which is why manufacturers have selected them over more exotic alternatives.
| Refrigerant | GWP | Classification | Status |
|---|---|---|---|
| R-410A | 2,088 | A1 — non-flammable | Phased out in new equipment |
| R-454B | 466 | A2L — mildly flammable | Primary replacement, widely adopted |
| R-32 | 675 | A2L — mildly flammable | Common in some product lines |
| R-1234yf | 4 | A2L — mildly flammable | Used in some specialty applications |
The A2L Problem: Why This Transition Is Expensive
The catch — and the reason this transition is significantly more disruptive than just swapping one refrigerant for another — is that R-454B and R-32 are both classified A2L by ASHRAE. A2L means mildly flammable. The A1 classification of R-410A meant non-flammable.
That single change in flammability classification triggers a cascade of requirements that affects every manufacturer of equipment using these refrigerants:
- UL listings must be updated — equipment certified under A1 refrigerant safety requirements must be retested and relisted for A2L compatibility
- CSA certifications must be updated — same issue for Canadian market equipment
- AHRI performance certifications must be updated — capacity and efficiency ratings are refrigerant-specific
- ASHRAE 15 safety compliance must be verified — the refrigerant safety standard has specific provisions for A2L refrigerants
- Installation requirements may change — some A2L applications require leak detection or minimum ventilation that A1 installations did not need
For facility operators: If you are planning a new chiller installation, confirm with your contractor that the specified equipment uses a compliant refrigerant and that the installation will meet the applicable safety requirements for A2L refrigerants in your jurisdiction.
What This Means for Equipment Already in Service
If you have existing chillers running R-410A, they are not immediately affected. The Technology Transitions Rule restricts new equipment manufacturing — it does not require you to replace operating equipment on a schedule.
However, two practical realities will affect you over time:
- Servicing costs will rise. As R-410A production is phased down, the supply of refrigerant for service and top-off will shrink and prices will increase. This has already begun.
- Equipment replacement planning matters now. If you have older chillers running R-22 or R-410A and are planning replacements in the next three to five years, understanding the new refrigerant landscape now avoids surprises when you go to specify equipment.
The Timeline
AIM Act Signed
Congress authorizes EPA to phase down HFC production and regulate equipment transitions.
Technology Transitions Rule Finalized
EPA publishes refrigerant GWP limits by equipment category. Industry begins redesign and recertification cycle.
700-GWP Limit Takes Effect
New comfort-cooling and most chiller equipment must use refrigerants at or below 700 GWP. R-410A effectively ends in new products.
Transition Actively Underway
Most major manufacturers have released A2L-compatible product lines. R-454B and R-32 equipment is standard in new installations.
What Facility Operators Should Do Now
- Inventory your existing refrigerants. Know what refrigerant each of your chillers uses. This is essential for the leak management rules that took effect in 2026.
- Plan capital equipment timelines with refrigerant in mind. Aging R-410A equipment is not going to become cheaper or easier to service.
- Confirm new equipment specifications before purchase. Any new chiller you specify today should already be using an AIM Act-compliant refrigerant. Ask the manufacturer to confirm GWP and ASHRAE safety classification.
- Understand A2L installation requirements for your jurisdiction. Some local building and fire codes have already been updated for A2L refrigerants. Others have not yet caught up. Your contractor should know — but ask the question.
Official sources: The Technology Transitions Rule is at 40 CFR Part 84 Subpart G. The EPA Technology Transitions Program at epa.gov is the most current authoritative source.
Related: Your Commercial Chiller May Already Be Out of Compliance — the EPA’s 2026 Leak Management Rules ›
Questions About Your Chiller and the Refrigerant Transition?
AG Chill engineers can walk through how your system is affected and what makes sense for your operation — whether you are servicing existing equipment or specifying new.