As of 19 May 2026
R-454B vs R-410A vs R-32 in 2026: The AIM Act Refrigerant Transition Reality
The 2025 EPA AIM Act phase-down forced US residential AC manufacturers to transition from R-410A (GWP 2,088) to refrigerants below GWP 700. Most major brands chose R-454B (GWP 466). Daikin and selected Goodman models use R-32 (GWP 675). This page covers the practical 2026 install implications.
Refrigerant Quick Reference
| Refrigerant | GWP | Safety Class | Composition | 2026 Status |
|---|---|---|---|---|
| R-22 (Freon) | 1,810 | A1 | HCFC | Phased out 2020 |
| R-410A (Puron) | 2,088 | A1 | HFC blend | No new equipment after 2025 |
| R-454B (Puron Advance) | 466 | A2L | R-32 (68.9%) + R-1234yf (31.1%) | Most major brands 2026 |
| R-32 | 675 | A2L | Pure (single component) | Daikin lineup 2026 |
| R-1234yf | 4 | A2L | HFO | Mainly automotive |
The AIM Act Timeline
The American Innovation and Manufacturing (AIM) Act, enacted in December 2020, mandated an 85 percent phase-down of HFC refrigerant consumption in the US by 2036. The EPA implemented sector-specific rules in 2024 setting GWP ceilings for new equipment categories.
For residential AC and heat pumps: the GWP ceiling is 700 for new equipment manufactured after January 1, 2025. This forced retirement of R-410A (GWP 2,088) for new equipment manufacturing. R-454B and R-32 became the dominant compliant alternatives. R-1234yf (GWP 4) is technically compliant but primarily used in automotive AC due to operating pressure differences.
Separately under AIM Act, total US HFC production allowances are being reduced 10 percent annually starting 2024. This means R-410A becomes progressively more expensive to source over the next decade, even for service of existing equipment. Service cost increases of 15 to 40 percent on R-410A by 2030 are expected by industry consensus.
A2L Safety Class: What It Means
ASHRAE Standard 34 classifies refrigerants by toxicity (A nontoxic, B toxic) and flammability (1 no flame, 2L low-flammability, 2 flammable, 3 highly flammable). R-410A is A1 (nontoxic, no flame propagation). R-454B and R-32 are A2L (nontoxic, mildly flammable, flame propagation possible only at high concentrations and with ignition source).
Practical implications for residential installs: A2L systems require leak-detection sensors integrated into the indoor coil cabinet. These sensors monitor refrigerant concentration in the air handler space and automatically shut off operation if concentration exceeds the lower flammability limit (LFL). All major-brand 2026 model-year A2L equipment ships with these sensors built in.
Service implications: HVAC technicians need A2L-rated recovery machines, recovery cylinders, and leak detectors. EPA Section 608 certification training for A2L is now standard at HVAC schools. Older technicians without A2L training may need refresher courses (typically 4 to 8 hours, $200 to $500). For homeowners this is invisible, your installer's training is their responsibility.
R-454B vs R-32: Brand Selection
Carrier, Trane, Lennox, American Standard, Bryant, York, Rheem, and most Goodman 2026 models use R-454B. Daikin and a growing subset of Goodman 2026 models use R-32. Mitsubishi ductless lineup uses R-32 (which they have used in international markets for years).
R-454B advantages: closer match to R-410A operating pressures, easier transition for installers already trained on R-410A. Larger US installer ecosystem in 2026. Slightly lower GWP than R-32 (466 vs 675).
R-32 advantages: single-component refrigerant (no fractionation concerns on leak/recharge), simpler leak detection, well-established global service ecosystem (R-32 has been dominant in Europe and Asia for years), slight efficiency edge in some lab conditions. Daikin's vertical integration on R-32 means parts and service pipeline is mature globally.
R-410A Closeout Inventory Strategy
Distributors still have R-410A new-old-stock from pre-2025 manufacturing. This inventory is being sold at clearance pricing through 2026. Typical discount: $300 to $700 on a 3 ton install vs the equivalent R-454B model. For homeowners with short ownership horizon (3 to 5 years), this represents real savings.
Risks: long-term R-410A refrigerant cost will rise. Service for R-410A will become marginally more expensive over time as the supply phase-down progresses. By 2030 R-410A service may cost 20 to 40 percent more per pound than today. For an 8-12 year ownership window, the closeout savings can be partially eroded by higher service costs over the system's life.
Verdict: closeout R-410A is rational for short-term holders, marginal for medium-term holders, and probably the wrong call for long-term holders staying 10+ years.