Refrigerant is the fluid that carries heat between the indoor and outdoor units. You never see it, but it decides a lot: which rules apply to the system, how often it needs leak checks and what a repair costs. For most homes and small businesses the choice today is simple, because new single split systems use R32 or lower-GWP refrigerants. If you own an older R410A system, the picture is more nuanced.
The numbers: GWP and CO2 equivalent
Global warming potential (GWP) compares a gas’s climate impact with carbon dioxide. The figures in law (Regulation 517/2014, Annex I) are:
| Refrigerant | GWP | 3 kg charge in tonnes CO2 equivalent |
|---|---|---|
| R32 | 675 | 3 × 675 ÷ 1000 ≈ 2.0 tCO2e |
| R410A | 2088 | 3 × 2088 ÷ 1000 ≈ 6.3 tCO2e |
So the same amount of R32 has about a third of the climate impact of R410A. R32 is also a single refrigerant rather than a blend, which makes recovery and recharging more straightforward.
Why it matters for leak checks
Under GB F-gas rules, systems with 5 to less than 50 tonnes CO2 equivalent of refrigerant need a leak check at least every 12 months, and 50 to less than 500 tonnes every 6 months (GOV.UK leak checks). Fitting automatic leak detection lets you double the interval.
That has a practical effect. A system holding 3 kg of R410A is around 6.3 tonnes and needs a legal leak check at least once a year. The same charge of R32 is around 2.0 tonnes and falls below the threshold. Small domestic R32 splits often hold well under 1 kg: a 2.5 kW Fujitsu/GENERAL Designer unit holds 720 g (data page). Responsibility for leak checks is shared between the equipment operator and the service technician, so businesses with larger R410A systems should keep records. See /air-conditioning-fgas-regulations-business-guide/.
What the rules say about new equipment
GOV.UK’s F-gas bans guidance explains that from 2025, new single split systems holding less than 3 kg of refrigerant can’t use F gases with a GWP above 750. R410A, at 2088, is well above that; R32, at 675, is below it. There are exceptions, including larger splits and air-to-water single splits. Movable (portable) air conditioning using HFCs with a GWP above 150 is already banned.
Great Britain keeps its own version of the F-gas rules, and the supply of HFCs is being phased down in steps. Our /f-gas-phase-down-2027/ guide covers what the next step means.
Want it done properly? AirCon Doctor installs, repairs and services air conditioning and heat pumps across London and the South East, from our base in East Grinstead. We’re an F-Gas certified company and NICEIC approved. Get a fixed-price quote.
If you have an R410A system
- It’s legal to keep using and repairing it. There’s no requirement to replace a working R410A system.
- Refrigerant is getting scarcer. As the phase-down tightens, R410A for top-ups is likely to become harder and dearer to buy.
- Leaks deserve a proper fix. Topping up without finding the leak wastes refrigerant and money. See /air-conditioning-regas-guide/.
- Plan ahead. If the system is older and needs a big repair, compare the cost with an R32 replacement. Our /r410a-r22-air-conditioning-repair-or-replace/ guide helps with that decision.
Very old systems may still use R22, an ozone-depleting refrigerant. Servicing with new R22 ended years ago, so those systems are usually replaced rather than repaired.
Is R32 safe?
R32 is classed as mildly flammable (A2L). That sounds alarming, but systems are designed and installed to strict standards, and the charge in a home split is small. It does mean the installer must follow the manufacturer’s rules on room size, pipe joints and ventilation, and use suitable tools. That’s one more reason to use an F-Gas certified company.
What comes after R32?
Some manufacturers now offer natural refrigerants in wall units. Mitsubishi Electric’s MSZ-RZ uses R290 (propane), which the company gives a GWP of 0.02, and includes a refrigerant sensor for early leak detection (MSZ-RZ page). R290 is more flammable than R32, so the installation rules are stricter. For most homes in 2026, R32 remains the mainstream choice, with R290 an option worth discussing.
What we do
Every new single split we install uses R32 or a lower-GWP refrigerant. We service and repair R410A systems and give you an honest repair-or-replace view with figures. We’re an F-Gas certified company, and every installation comes with commissioning and F-Gas records. See /air-conditioning-installation/ and /air-conditioning-repair/.
Quick answers
Is R410A being banned?
New single split systems under 3 kg can no longer use refrigerants with a GWP above 750, which rules out R410A in those. Existing R410A systems can still be used and repaired legally.
Can I put R32 in an R410A system?
No. A system must only be charged with the refrigerant it was designed for. Changing refrigerant means replacing the equipment.
What is the GWP of R32?
R32 has a GWP of 675, compared with 2088 for R410A, under Annex I of Regulation 517/2014.
Related services
- Air conditioning regas
- Air conditioning repair
- Air conditioning installation
- Air conditioning servicing
More advice
- The 2027 F-Gas Phase-Down in Great Britain: What It Means for You
- R410A and R22 Air Conditioning: Repair or Replace?
- Air Conditioning Regas: What It Is and When You Need It
- Air Conditioning F-Gas Regulations: What Businesses Must Know
- All advice
This guide is general information, checked against the sources linked on 30 October 2026. It isn’t legal, tax or financial advice. Rules, grants and product ranges change, so check the current position before you rely on it.