The short answer
R22 damages the ozone layer and can no longer be used to service equipment, so a leaking R22 system usually means replacement. R410A is still widely used and can be serviced, but its high global warming potential means most new systems use R32.
On this page
If your air conditioner was fitted some years ago, it may use an older refrigerant. The two you're most likely to meet are R22 and R410A, and they're in very different positions. R22 is at the end of its life. R410A is still common, but new equipment has moved away from it.
Finding out which refrigerant you have
The rating plate on the outdoor unit shows the refrigerant type and how much the system holds, usually labelled with words such as "refrigerant" and "charge". The installation paperwork or manual should show it too. If the plate can't be read, an engineer can usually tell from the model details.
R22
R22 is an HCFC. It was widely used in air conditioning for decades, but it damages the ozone layer, and it has been phased out under the same international agreement that ended CFCs.
For an R22 system, that means:
- R22 has not been allowed for servicing equipment since 2015, so a system that has lost refrigerant can't be topped up with it;
- any repair that involves opening the refrigerant circuit is difficult, and replacement is usually the realistic option;
- a system that still works and doesn't leak can be left running, but it's sensible to plan for its replacement rather than wait for it to fail in hot weather;
- when it's removed, a qualified engineer must recover the refrigerant rather than release it.
Some older systems were converted to run on substitute refrigerants. Whether that was done, and done well, varies, so an engineer should check the rating plate and any added labels before working on one.
Any R22 system is old by now, and its efficiency is usually well below that of a modern inverter system. How long air conditioning lasts covers the signs that a system is nearing the end.
R410A
R410A is an HFC blend that replaced R22 in new equipment. It doesn't harm the ozone layer, and it was the usual choice for air conditioning for many years.
Its drawback is its effect on the climate. With a global warming potential of 2,088, a kilogram of R410A escaping has roughly three times the warming effect of a kilogram of R32.
For an R410A system, that means:
- it can still be serviced and repaired with R410A by a qualified engineer;
- rules on high-GWP refrigerants are tightening and the amount that can be sold is being reduced, which can affect how easy R410A is to get over time;
- most new wall-mounted systems use R32 instead;
- mandatory leak checks apply from about 2.4 kg of R410A. Most single-room systems hold less than that, but some larger or multi-room systems may hold more.
Comparing the two
| R22 | R410A | |
|---|---|---|
| Damages the ozone layer | Yes | No |
| Global warming potential | 1,810 | 2,088 |
| Can be topped up with the same refrigerant | No | Yes |
| Usual next step after a leak | Replace | Repair or replace |
Replacing an older system
A replacement system will almost certainly use a different refrigerant. Whether the existing pipework can be reused depends on its condition and size and on the new unit's installation instructions; often it's simpler to fit new pipes, particularly when moving away from R22.
Either way, the old system's refrigerant has to be recovered before anything is disconnected. Removing and disposing of an old system explains how that's done.
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.
- R32 refrigerantR32 is the refrigerant in most new wall-mounted systems. It carries heat efficiently, usually needs less of it than R410A, and has about a third of R410A's global warming potential. It is mildly flammable, so it's handled with specific precautions.
- How long air conditioning lastsA well-installed, regularly serviced wall-mounted system typically lasts around 10 to 15 years, and some keep going longer. How long yours lasts depends on installation quality, how hard it works, where the outdoor unit sits and how it's looked after.
- 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.