R32 vs R410A: Published GWP Figures and UK F-Gas Implications

The short answer to r32 vs r410a: under IPCC AR4 100-year values, R410A carries a global warming potential of about 2,088 while R32 is listed at 675 [7]. The AR5 values are 1,924 for R410A and 677 for R32 [7]. Updated IPCC AR6 data, however, put pure R32 higher, at a 100-year GWP of 771 with a 20-year figure of 2,690 [2]. For context on the same 100-year AR4 basis, R454B is 466 [7], and R290 (propane) is 3.3 [8] — a value that AR6-based summaries revise down dramatically to 0.072 over 100 years and 0.02 over 20 years [4]. The 100-year IPCC numbers are the ones regulators and F-gas paperwork normally use, which is why the same refrigerant can appear with two different figures depending on which assessment report you are reading.

Sources: [7], [8]

The pattern holds whichever report you use: R410A sits in a class of its own for climate impact, and the gap between it and everything newer is not marginal.

What GWP means for air conditioning refrigerants

Global warming potential compares the warming effect of one kilogram of a gas with one kilogram of carbon dioxide, which is fixed at 1 [3]. A refrigerant with a GWP of 675 warms the atmosphere roughly 675 times as much as the same mass of CO2, measured over a chosen period.

That period matters more than most product literature admits. The 100-year horizon is the regulatory reference, and it is what appears in equipment labelling and F-gas calculations. But many HFCs break down in the atmosphere in a decade or two, so their 20-year figure is much higher than their 100-year one. AR6 publishes a 20-year value for R32 that is several times its 100-year value [2] — relevant if you care about warming between now and the 2040s rather than the 2120s.

One discipline is worth keeping: never read AR4, AR5 and AR6 figures from the same unlabelled column. A table showing R32 at 675 is an AR4 table, and one showing 677 is AR5 [7]. A table showing R32 at 771 is AR6 [2]. Mixing them makes a refrigerant look better or worse than the rules actually treat it.

r32 vs r410a published GWP figures

IPCC AR4, 100-year horizon: R410A is 2,088; R32 is 675; IPCC AR5, 100-year horizon: R410A is 1,924 and R32 is 677 [7] [6]. Within each report the two figures share one basis, so compare them within a report, never across reports.

IPCC AR6, 100-year horizon: pure R32 is 771 [2].

R410A is the legacy blend, part R32 and part R125, and its high published GWP is why regulators targeted it first in new equipment. R32 was adopted across much of the split-system market as the lower-GWP successor, and on AR4 or AR5 arithmetic that argument is straightforward.

The AR6 revision is where installer marketing tends to go quiet. Moving from 677 on AR5 to 771 on AR6 does not sound dramatic, but it pushes R32 above the GWP thresholds that tightening rules are converging on for new air conditioning and heat pump equipment. R32 is best understood as a transitional HFC: a genuine improvement on R410A, not a permanent destination. If you are weighing up options for a single split air conditioning system, that distinction affects resale and future servicing more than it affects performance today.

Not sure which system suits your home? The planner compares the options and says what to keep and what to change, in about a minute. Plan my home → or watch it work (24 s) ↓

R454B and R290 GWP compared to R32

R454B is an A2L HFC blend promoted as the R410A replacement in larger split and packaged equipment. Its AR4 100-year GWP is 466, or 467 on AR5 [7], below R32 on either basis and under a quarter of R410A. It remains a fluorinated blend, so it stays inside F-gas quota territory and inside the long-term phase-down.

Propane sits in a different category altogether. AR4 tables list R290 at 3.3, against 1,430 for R134a and 3,922 for R404A [7] [8], so propane’s figure is about 99.8% and 99.9% lower respectively. AR6-based manufacturer summaries revise that down again to 0.072 over 100 years and 0.02 over 20 years [4]. The practical reading offered by heat pump makers is that if a kilogram of R290 escapes, its climate contribution is negligible against CO2 at GWP 1 [3]. As a non-fluorinated natural refrigerant, R290 also falls outside EU F-gas quotas.

Neither is a retrofit. R290 in particular means different charge limits, pipe runs and siting decisions, which is a design question at specification stage rather than a swap.

What the F-gas phase-down means for existing systems

The revised EU F-gas Regulation tightens the HFC phase-down and sets GWP limits on new air conditioning and heat pump equipment, with a full phase-out of HFC consumption as the endpoint [1]. Those provisions squeeze what manufacturers can bring to market. They are not a retroactive order to strip out installed kit, and the EU calendar is not automatically your domestic obligation in the UK — check current UK guidance for the dates that bind you [5].

What the phase-down actually does to an existing owner is economic. As quotas tighten, higher-GWP gas gets scarcer and dearer, and new equipment designed around it stops being available. Your R410A system does not become unlawful. It becomes a system whose repair costs are drifting upward while the supply chain moves on around it. That is the stranded-asset risk worth planning for, particularly on larger commercial plant where a single recharge is a meaningful invoice.

Can I still service an R410A or R32 system

Yes, with caveats that scale with system size. UK guidance sets out that operators may not use virgin F-gases to refill existing refrigeration systems where the system holds F-gas equivalent to 40 tonnes of CO2 or more and the gas is a higher-GWP F-gas [5]. Most domestic splits are nowhere near that charge. Larger commercial installations can be, and for those the practical path shifts toward reclaimed and recycled refrigerant, which has its own time-limited availability under current rules.

Alongside that sit the ordinary duties: leak checks at the intervals set by charge size, recovery of gas at decommissioning, records kept, and work carried out by qualified personnel [5]. A maintenance plan that documents leak checks is where those obligations actually get met.

r32 vs r410a: which refrigerant should I choose

What is the GWP of R32 vs R410A? AR4 100-year: 675 and 2,088; AR5 100-year: 677 and 1,924 [7]. AR6 100-year for R32: 771 [2].

Is R32 a low-GWP refrigerant? Lower than R410A, clearly. Low in absolute terms, no — 771 on AR6 is above the thresholds newer rules aim at [2].

Why do tables differ? They come from different IPCC reports: AR4, AR5 or AR6. Ask which one your installer is quoting.

Will R410A be banned? New equipment is being restricted; owning and servicing an existing system is a separate question [5].

Three questions to put to any installer: which refrigerant, which IPCC report their GWP figure comes from, and how they will recover the gas at end of life. If you are still deciding on equipment type, the heat pump versus air conditioning comparison covers the design side.