R-290 propane air conditioners: the refrigerant Europe is switching to

Updated September 5, 2026 · Claude AC · 2 sources cited

Walk into a European showroom today and almost every split on the wall runs on R-32. Open the same manufacturer’s roadmap for 2028 and a growing share of it says R-290 — which is propane. That is not a marketing fashion or a green flourish. It is the mechanical consequence of one number written into European law, and it changes what you should ask before signing a quote this year.

What R-290 actually is

R-290 is refrigerant-grade propane: the same molecule as the camping bottle, purified to a far higher specification and sealed inside a welded circuit. Its global warming potential is effectively nothing — 3 under the older assessment values, revalued at 0.02 in the European Commission’s current listing — against 675 for R-32 and roughly 2,000 for the R-410A still circulating in older machines. Thermodynamically it is a genuinely good refrigerant, with high latent heat and low viscosity, which is why engineers liked it long before the regulator did.

It is also flammable, classified A3 in the refrigerant safety scheme: low toxicity, higher flammability. That single letter is the whole story of why propane took thirty years to reach a wall-mounted air conditioner, and why the rules around it are written in grams.

Worth keeping in proportion: propane has run European domestic fridges and freezers since the 1990s. The appliance humming in your kitchen almost certainly holds somewhere around 40 to 60 grams of it, and has done so, uneventfully, for its whole life.

Why the switch runs on a schedule

Regulation (EU) 2024/573 sets a dated ceiling rather than a preference. From 1 January 2027, split systems of 12 kW and below may not be placed on the EU market containing a fluorinated gas with a GWP of 150 or more. R-32, at 675, sits well above that line. Equipment above 12 kW follows on its own steps — GWP 750 from 2029, 150 from 2033 — and the HFC quota phase-down squeezes the supply of everything else in parallel. The full timetable and what it means for equipment you already own is set out in our guide to the F-gas Regulation 2024/573.

Manufacturers have two legal routes below GWP 150: synthetic A2L blends such as R-454C, or propane. The blends are easier to handle and slot into familiar service practice; propane is cheaper as a commodity, immune to any future phase-down because it is not a fluorinated gas at all, and thermodynamically the stronger performer. Most catalogues are hedging with both.

The safety question, answered in grams

Nobody manages propane risk with reassurance; they manage it with charge limits, and the limits are specific.

• Below about 150 g, an appliance carries no room-size condition at all — the quantity is too small to build a flammable concentration in any habitable space.
• Above that, the permitted charge climbs with the floor area of the room the refrigerant could leak into. A bigger room legally permits a bigger charge, up to a hard ceiling.
• The 2022 edition of the international appliance standard IEC 60335-2-40 lifted that ceiling for factory-sealed comfort equipment towards 988 g of A3 refrigerant, conditional on engineered mitigations: refrigerant detection, forced airflow that dilutes a leak, and shut-off valves that isolate the indoor portion of the charge. Earlier editions allowed only a few hundred grams, which is precisely why propane splits did not exist.
• The European standard EN 378 permits larger indoor quantities under stricter room-area rules, but it is written for field-assembled plant rather than the factory-built appliances most homes buy.

The practical translation is architectural. A monobloc — an air-to-water heat pump or an outdoor cooling unit — keeps its entire charge outdoors, where a leak disperses into open air, so the room-size arithmetic never applies to your living space. A split pushes refrigerant through the wall into the room, so its indoor charge is what the standard governs. That is why propane arrived in heat pumps years before it reached wall splits, and why early R-290 splits are modest in capacity: the charge budget is the design constraint.

Where you will meet R-290 first

Four product families, in the order they are reaching European buyers.

• Air-to-water heat pumps. Already mainstream, already propane in several ranges, and unaffected by indoor charge rules because the refrigerant never enters the house.
• Portable and window units. Small charges make propane straightforward here; the Commission lists it as a direct replacement for R-410A and R-32 in moveable room air conditioners. The efficiency ceiling of the format still applies — see portable air conditioners.
• Wall monoblocs with no outdoor unit. A natural fit, since the circuit sits in the wall aperture. Their broader trade-offs are covered in our guide to air conditioning without an outdoor unit.
• Air-to-air splits. The last and hardest category, arriving now in smaller capacities. Compare against current equipment on our split AC page.

Does it cool better?

Modestly, and not always in the way buyers expect. On the cooling side the seasonal efficiency of a good R-290 machine sits in the same band as a good R-32 machine; the label numbers overlap heavily, and unit-to-unit engineering matters more than the gas. The clearer advantages show up in winter, where propane sustains capacity and higher output temperatures at low outdoor conditions better than most alternatives, and in durability of the decision: a propane machine cannot be caught by a future quota step.

What has not changed is the ranking of what actually determines your bill. A correctly sized, well-installed R-32 unit will comfortably out-perform an oversized or badly commissioned R-290 one. Start from the load, not the refrigerant — our method for sizing an air conditioner in kW gives a defensible figure to bring to an installer.

Servicing: where the industry is still catching up

An F-gas certificate does not, by itself, authorise work on flammable natural refrigerants — propane sits outside the F-gas Regulation entirely, and competence is handled through separate national training and equipment requirements. In practice this means a smaller pool of qualified technicians today, spark-free tooling, different brazing and evacuation discipline, and no culture of casually topping up a leaking system. That last point is a feature rather than a limitation: as explained in our guide on refrigerant and regassing, a sealed circuit should never lose gas, and a system that needs a recharge needs a leak repair. Before you commit, ask the questions in our guide to choosing an installer and reading the quote — and add one more: who services this machine in five years?

Buy now, or wait for 2027?

Frequently asked questions

Is an R-290 air conditioner safe in a bedroom?

Within its certified limits, yes — and those limits are exactly what the room-area rule enforces. An appliance holding less than roughly 150 grams carries no minimum room size; above that, the manufacturer states a minimum floor area for that specific model, and installing it in a smaller room is what would make it unsafe. Check that figure against the room before purchase, not after. Basements, spaces below ground level and rooms with floor-level drains deserve particular attention, because propane is heavier than air.

Will my R-32 unit become illegal in 2027?

No. The 2027 threshold governs placing new equipment on the market. Existing installations may be used, serviced and repaired indefinitely, and R-32 remains widely available for years. What tightens gradually is price and supply of virgin gas as the quota steps down — a reason to treat a major circuit repair on an ageing machine as a replacement decision, not a reason to rip out a working one.

Can I install an R-290 monobloc myself?

The refrigerant circuit, no. Even where propane falls outside F-gas certification, national rules on flammable refrigerants, plus the electrical work and the wall penetration, put this firmly in professional territory — and a self-installed appliance generally voids both the warranty and your insurer’s patience. Our guide on installing air conditioning yourself sets out what a homeowner may legally do.

Is propane cheaper to buy or to service?

The gas itself costs a fraction of any HFC, but that is a trivial share of the price of a machine. Today an R-290 unit typically carries a small premium for its safety hardware and its novelty, and servicing can cost more where qualified technicians are scarce. Expect both gaps to narrow sharply as 2027 approaches and volume moves. Any figure quoted more precisely than that, this early in a market, is guesswork.

Does the same 2027 date apply outside the EU?

Great Britain runs its own retained F-gas regime on a similar trajectory rather than the identical calendar, and Northern Ireland follows EU rules. Switzerland and Norway track the EU closely in practice, because manufacturers do not build separate product lines for small markets. Country-by-country context sits on the Europe hub.

Read next

• The F-gas Regulation 2024/573: what changes for cooling in Europe
• How far can the outdoor unit sit from the indoor unit?
• Does an air conditioner need regassing? Refrigerant, leaks and EU rules
• The carbon footprint of cooling a European home
• When to run your air conditioning: Europe’s tariff clock and the pre-cooling trick

All Europe guides →