The short answer
F-gas rules in Great Britain require anyone installing, servicing or removing a split system to hold the right qualification, and ban releasing refrigerant. A typical home system is well below the size that needs mandatory leak checks.
On this page
F-gases are the fluorinated gases used as refrigerants in most air conditioning. They are strong greenhouse gases if they escape, so the rules focus on keeping them sealed inside the system and on who is allowed to work on it. This guide covers Great Britain; Northern Ireland follows different rules.
What the rules cover
For a homeowner, the F-gas rules come down to a few points.
- Refrigerant must never be released. It stays sealed in the system, and when a system is removed, a qualified engineer recovers it.
- Qualified people only. Anyone installing, servicing or dismantling equipment that contains F-gas refrigerants needs the right F-gas qualification.
- Certified businesses. A business doing the work needs a company F-gas certificate from a certification body.
A split system is connected into a sealed refrigerant circuit on site, so fitting one isn't DIY work. That includes kits sold as easy to fit yourself: the rules apply to anyone installing the equipment. Why installation needs a certified engineer explains what the work involves.
Portable air conditioners and other self-contained units arrive sealed from the factory, so plugging one in doesn't involve handling refrigerant. The refrigerant inside still has to be recovered when the unit is eventually scrapped.
Refrigerants and their global warming potential
Each refrigerant has a global warming potential, or GWP: a measure of how much heat it traps over a set period, compared with the same weight of carbon dioxide. Global warming potential explained goes into how it's worked out.
| Refrigerant | GWP | Notes |
|---|---|---|
| R32 | 675 | Used in most new split systems; mildly flammable (A2L) |
| R410A | 2,088 | Common in systems fitted before R32 took over |
| R22 | 1,810 | Ozone-depleting; not allowed for servicing since 2015 |
| R290 (propane) | 3 | Flammable (A3), which limits amounts in room-sized systems |
These are the values used in the GB F-gas rules. Rules on refrigerants with a high GWP are tightening, and the industry is moving towards lower-GWP options.
R22 is an HCFC, which damages the ozone layer, and it falls under separate rules on ozone-depleting substances. An R22 system can keep running, but it can't be topped up or serviced with R22, which limits what can be done when it develops a fault. Older refrigerants: R22 and R410A covers the options.
Leak checks and CO2 equivalent
Mandatory leak checks apply to systems holding 5 tonnes of CO2 equivalent or more. The CO2 equivalent depends on both the amount of refrigerant and its GWP:
kilograms of refrigerant × GWP ÷ 1,000 = tonnes of CO2 equivalent
A typical home split system holds roughly 0.5–1.5 kg of R32, which works out at about 0.3–1 tonne, far below the threshold. With R410A, about 2.4 kg reaches 5 tonnes, so some larger R410A systems, such as multi-splits, can reach it and need leak checks.
The refrigerant type and amount are usually shown on a label on the outdoor unit, and a good installer records them at commissioning.
Below the threshold, refrigerant still shouldn't be escaping. The circuit is sealed, and refrigerant isn't used up in normal running. A system that has lost refrigerant has a leak somewhere, which needs finding and repairing rather than just topping up.
What this means for you
The rules mostly govern the people who work on your system, but they shape a few decisions you make.
- Choosing an installer. Ask to see the company's F-gas certificate, and check that the engineers who will handle refrigerant hold the right qualification.
- Keeping records. Keep the commissioning record showing the refrigerant type and amount. It's useful for servicing, repairs and selling.
- Servicing and repairs. Any work on the refrigerant circuit, including adding refrigerant, needs a qualified engineer.
- Moving or removing a system. A split system can't simply be unbolted and taken away. Disconnecting one means handling the refrigerant, which is work for a qualified engineer, and a system removed for good has its refrigerant recovered, as covered in Removing and disposing of an old system.
Related guides
- Refrigerants explainedA refrigerant is the fluid that carries heat around an air conditioner, boiling to absorb it and condensing to release it. Refrigerants differ in their pressures, efficiency, flammability and effect on the climate, which is why the choice matters.
- Global warming potential explainedGlobal warming potential (GWP) compares how much a gas warms the climate with the same mass of carbon dioxide, usually over 100 years. A refrigerant's GWP shows how much harm a leak would do, and it underpins the rules on refrigerants.
- Why installation needs a certified engineerA split system is joined into a sealed refrigerant circuit on site, and in Great Britain anyone doing that work needs the right F-gas qualification, with the business holding a company F-gas certificate. Poor work can cause leaks, damage and safety problems.
- Removing and disposing of an old systemAn old split system has to be taken out by a qualified engineer, who recovers the refrigerant before anything is disconnected. The units then go for recycling as electrical waste, and the holes and fixings left behind need making good.