R32 vs R454B for residential AC — picking your A2L
By DigiEntropy Engineering · 2026-02-21 · 6 min read
Residential air conditioning has moved to A2L mildly-flammable refrigerants. R32 dominates today's stock; R454B is the OEM-favoured successor. The decision drivers are GWP, COP at high ambient, manufacturer ecosystem, and the regulatory window.
About this post — Authored by an AI assistant using DigiEntropy's polynomial corpus, the universal compressor predictor, and the project's chart-generation tooling. Charts are produced by Python scripts that read the same database the live site queries; tables and formulas are pulled from the same engineering modules. Findings reflect the project's current dataset and methodology — send corrections or deeper questions to admin@digientropy.com.
The residential AC market has settled on A2L mildly-flammable refrigerants as the post-HFC default. R32 took the early lead — single-component, A2L, GWP 675 — and now ships in the majority of new split systems globally. R454B (Opteon XL41) is the OEM-favoured successor: GWP 466, A2L, R32-similar capacity, and one number lower on every F-Gas chart.
Which one do you pick for a 2026+ install? The honest answer is "it depends on the OEM and the climate" — both win cleanly in different cells of the decision matrix.
675 - R32 GWP (AR4) - single-component, A2L
R32 took the early lead — single-component, A2L, GWP 675 — and now ships in the majority of new split systems globally.
466 - R454B GWP (AR4) - R32 + R1234yf blend, A2L
R454B (Opteon XL41) is the OEM-favoured successor: GWP 466, A2L, R32-similar capacity, and one number lower on every F-Gas chart.
under 750 - F-Gas 2026 and 2030 status - both allowed
Both clear current F-Gas comfortably. R454B's GWP cushion is what makes it the OEM-favoured successor for the next regulatory step.
1.5 K - R454B glide - R32: 0 K
PH chart — R454B cycle at the same conditions. The 1.5 K glide is visible as a slight tilt in the constant-pressure limb inside the dome.
2-10 kW - typical residential AC sizes - both have enough compressor support
For a 2026 specification, both refrigerants have enough compressor support for typical residential AC sizes (2-10 kW).
10× - R32 wholesale stock vs R454B - most of Asia, much of Europe
Pick R32 if you're in a market where R32 wholesalers stock 10× more than R454B (most of Asia, much of Europe).
The headline comparison
R32 vs R454B, the headline numbers - GWP (AR4)
GWP (AR4): R32 675, R454B 466.
R32 vs R454B, the headline numbers - Volumetric capacity vs R410A
Volumetric capacity vs R410A: R32 5 %, R454B -3 %.
R32 vs R454B, the headline numbers - COP at 35 °C ambient vs R410A
COP at 35 °C ambient vs R410A (typical): R32 -2 %, R454B 2 %.
Both clear current F-Gas comfortably. R454B's GWP cushion is what makes it the OEM-favoured successor for the next regulatory step.
The headline comparison table
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