R-22 vs R-32 vs R-410A vs R-134a vs R-404A: what does each do?

The five at a glance

How each earned its niche

Applications follow thermodynamics. R-22 balanced pressure, capacity and oil compatibility so well it ran everything from window units to industrial plants for half a century — which is why the servicing tail matters so much now. R-410A was engineered as its air-conditioning successor: ~50–60% higher operating pressure allowed more compact coils and compressors, at the cost of all-new components. R-32 — literally half of the R-410A blend — stands alone with a GWP one-third as high, roughly 20–30% lower charge for the same duty and, per Daikin's published testing, up to 12% better efficiency. R-134a's moderate pressures and A1 rating made it the automotive and appliance default. R-404A was formulated for deep-freeze duty: strong low-temperature capacity with near-zero glide.

The selection rules that never change

Three rules govern every choice. The equipment decides, not the buyer: a system is designed around one refrigerant's pressures, oil and expansion device — you match the nameplate, you do not "upgrade" the gas (see why mixing is prohibited). Class changes handling: four of the five are A1, but R-32 is mildly flammable A2L with its own tooling and charge-limit rules (A2L guide). Regulatory trajectory is a cost input: R-22 supply shrinks by quota; R-404A's 3,922 GWP makes it the most exposed HFC once Kigali bites in 2028.

Matching gas to sector

In our order book the mapping is consistent: AC service and installation trade draws R-32 and R-410A with R-22 for the legacy base; automotive workshops and appliance service pull R-134a; cold storage, ice-cream and food processing run R-404A; pharma sites buy across the range for HVAC plus HCFC-22 as feedstock. Sector-by-sector detail lives on the industries page.

The two-question shortcut for unfamiliar equipment

Field reality: equipment arrives unlabelled, secondhand, or imported, and someone must decide what gas it takes. Two questions resolve nearly every case. Question one — what does the nameplate say? The refrigerant designation stamped by the OEM is the answer; everything else is commentary. Charge quantity, design pressures and oil type on the same plate confirm it. If the plate is gone, the service literature for the model number replaces it. Question two — if truly undocumented, what do the pressures say? A static cylinder-and-gauge check at known ambient temperature places the fluid on a saturation curve: R-22-era pressure signatures differ from R-410A/R-32's by the 50–60% margin detailed in the pressure guide, and a refrigerant identifier settles ambiguous cases at the valve. What the shortcut forbids is inference from age, size or looks — the 2006–2024 transition years produced visually identical units on different fluids, and guessing wrong crosses the one line the industry treats as absolute (never mix). One more habit worth stealing from good AMC operators: when the fluid is finally confirmed, relabel the unit yourself with gas and oil, dated. Thirty seconds of marker pen converts the next visit — yours or a stranger's — from forensic work back into service work, and it is the cheapest reliability upgrade an unlabelled fleet can get.

Related: R-22 vs R-410A in service · Why R-32 is winning · Industries we supply