A call we get a few times a year goes the same way. The air conditioning in an office or a server room has been limping along for a couple of summers, somebody finally books an engineer, and the engineer comes back with one sentence that rewrites the maintenance budget: you cannot regas that, it is on R22. The unit is running. The refrigerant is the problem, and there is no legal way to put more of it in.
Most of those systems are between 15 and 25 years old. A fair number were converted years ago onto R407C, the standard R22 replacement of its day, and that gas is now heading down the same road. This post is for whoever signs the repairs on that plant.
R22 has been banned for servicing in the UK since 1 January 2015. If an R22 system loses its charge it cannot legally be refilled, so any refrigerant-side fault effectively ends the system. R407C is still serviceable today, but it is an HFC with a global warming potential of 1,774, and the January 2027 quota step will tighten its supply. Repairs that do not touch the refrigerant circuit are still legal and often worth doing on both gases. The real question is not what the gas costs. It is whether the plant is worth gassing at all.
How to tell which gas your old air conditioning system uses
Start with the nameplate on the outdoor unit. It will state the refrigerant, usually as R22 or HCFC-22, R407C, R410A or R32, along with the factory charge in kilograms. That plate is the first thing our engineers photograph, because everything else in the conversation hangs off it.
Age is a decent cross-check. A split or VRF system installed before about 2010 that has never been converted is almost certainly still on R22. Kit from roughly 2002 to 2010 was commonly converted to R407C or supplied on it from new. After about 2013, most new commercial plant arrived on R410A, and the newest systems run on R32. If the plate is unreadable, your commissioning paperwork or last service report should say, and if a system has been retrofitted at some point the plate can lie, so the service records win that argument.
If you want the wider picture of what each of these gases is and why the industry keeps changing, our guide to air conditioning gas types covers the whole family.
What the R22 ban actually says
R22 is a hydrochlorofluorocarbon, and it damages the ozone layer. It sits in the same legal family as the other ozone-depleting substances, not the F-Gas family, and the schedule that killed it is Regulation (EC) No 1005/2009. Article 11 of that regulation ended the use of virgin HCFCs for maintenance and servicing from 1 January 2010, then permitted reclaimed and recycled gas only "until 31 December 2014", for "the maintenance or servicing of existing refrigeration" and air conditioning equipment (Regulation (EC) No 1005/2009, Article 11).
Since New Year's Day 2015, there has been no legal way to charge any R22 into a system in the UK. Not virgin, not reclaimed, not a cylinder somebody has had in the back of the stores for a decade. Anyone offering to top up an R22 system today is offering to break the law, and I have watched that offer get made.
What an R22 leak means in practice
The rule that surprises people is the one about keeping the system. GOV.UK puts it plainly: "You must not use ODS in new equipment or to service existing equipment", but "you can still use equipment that contains ODS as long as it is not leaking" (Ozone-depleting substances, GOV.UK, which lists HCFC-22 with an ozone depletion potential of 0.055). Owning an R22 system is not illegal. Running one is not illegal. Letting it leak is, and refilling it is.
That creates a split personality in repairs. Anything on the electrical side is still an ordinary job: a failed fan motor, a tired capacitor, a corroded contactor, a dead PCB, a blocked condensate pump. We fix those on R22 kit regularly and they are often worth fixing, because the repair does not touch the gas. The refrigerant side is different. A pinholed coil, a weeping flare joint, a compressor terminal leak. Any of those means the charge comes out, and once it comes out it cannot go back.
A failed fan motor on an R22 condenser is a repair. A pinhole in the coil is a funeral. When that second one lands, the honest options are a refrigerant conversion or a new system, and our air conditioning repair service will tell you which before anyone spends money on parts.
R407C: serviceable today, squeezed from 2027
R407C was the industry's answer to R22, a blend of R32, R125 and R134a that worked in the same sort of plant at similar pressures. It contains no chlorine, so it never faced the ozone rules. It is an HFC instead, which puts it inside the F-Gas phase-down.
Its global warming potential is published on the GOV.UK list of F gases: R-407C comes in at 1,774, with the note that "Global warming potential (GWP) figures in these tables are rounded to the nearest whole number" (Fluorinated gases (F gases), GOV.UK). There is no servicing ban on R407C and none scheduled as of October 2026. You can repair a leak, recharge and carry on, provided the leak duties are met.
The pressure is economic rather than legal. The HFC quota steps down again on 1 January 2027, and we have written separately about what the 2027 quota step does to refrigerant supply. A gas at GWP 1,774 eats quota faster than the low-GWP alternatives, so it gets scarcer and dearer ahead of the pack. For comparison, R32, the gas most new air conditioning has moved to, sits at 675 on the same list.
Worth saying out loud: most R407C systems are now 15 to 25 years old. The gas is rarely the real problem. It is the excuse the system finally gives you to deal with it.
The duties that still come with an R407C system
Because R407C is an F gas, the leak-check regime applies, and the threshold is measured in CO₂ equivalent rather than kilograms. The bands are at least once every 12 months from 5 to less than 50 tonnes CO₂e, every 6 months from 50 to less than 500, and every 3 months at 500 or more, with automatic leak detection doubling each interval (Checking F gas equipment for leaks, GOV.UK).
Do the sum on a typical R407C VRF system. Ten kilograms of charge at GWP 1,774 works out at 17.7 tonnes CO₂e, which puts it firmly in the annual check band. Miss those checks and the conversation with your insurer after a major loss gets uncomfortable. We have covered the full operator duties in our guide to the F-Gas rules for businesses.
Retrofitting: when conversion works and when it is money into a corpse
There are genuine retrofit refrigerants for R22 systems. Blends such as R438A and R422D were engineered to run on the mineral oils R22 compressors lived on, at pressures the old pipework can take. We have done conversions that gave a sound system another five or six useful years, and I am not going to pretend the option does not exist.
The limits are equally real. A conversion usually costs some capacity, because none of the blends matches R22 exactly. The expansion valve and seals are two decades old and were not chosen for the new gas. The compressor, which is the expensive part, does not get any younger for being fed a different refrigerant. If the compressor fails eighteen months after you have paid for a conversion, you have bought the same replacement twice.
R407C conversions are a thinner market still. The low-GWP successors are mostly mildly flammable A2L blends, and the vast majority of R407C-era equipment was never rated for a flammable charge. That is not a drop-in conversation. It is a manufacturer approval conversation, and most of the time the answer is no.
Our rule is simple. Only convert a system that is sound in every other respect, get the assessment in writing before the work, and walk away from anyone who quotes a conversion over the phone without looking at the plant.
Repair, retrofit or replace: an honest table by symptom
| Symptom | Sensible route | Why |
|---|---|---|
| Failed fan motor, capacitor, contactor or PCB on either gas | Repair | The refrigerant circuit stays closed, so the R22 ban does not bite and the rest of the system may have years left |
| Small leak on an otherwise healthy R407C system | Repair and recharge | Gas is still available; find and fix the leak first, as the law requires, then recharge |
| Small leak on an R22 system | Replace, or price a conversion | The charge cannot legally be replaced, so the repair has no gas to end with |
| Compressor failure on R22 | Replace | A conversion plus a compressor on a 20 year old shell costs more than it returns |
| Compressor burnout on R407C | Replace in most cases | Acid clean-up, new compressor and a recharge buys you back an old system with old pipework |
| Repeated leaks across several circuits or joints | Replace | The pipework is corroding as a set, and chasing leaks one at a time is the expensive way to learn that |
| System runs but cools poorly | Assess before anything | Could be charge, could be airflow, could be a system that was undersized the day it went in. Guessing is how money disappears |
Notice how few rows say retrofit. That is deliberate, and it is the thing the brochure articles get wrong. Conversion is a niche answer for a young-ish, otherwise healthy system. On plant old enough to be on R22, it is usually a stay of execution with an invoice attached.
What a modern replacement actually changes
Ignore the percentages in the sales brochures and look at what is verifiable. Since January 2014, every new air conditioner up to 12 kW placed on the market has had to meet a minimum seasonal energy efficiency ratio: 4.6 for units under 6 kW and 4.3 for units from 6 to 12 kW, under the Ecodesign regulation (Regulation (EU) No 206/2012, Annex I). A fixed-speed R22 split predates seasonal ratings entirely, and most of the decent new kit clears those floors by a wide margin.
The bigger change is the compressor. Old systems stop and start at full power every few minutes. Inverter systems modulate, so the compressor eases back once the room is at temperature instead of slamming on and off all day. On a system running long hours, that is where the electricity saving actually comes from, and it shows up in your bills rather than in a brochure figure. Our post on what air conditioning costs to run goes into the arithmetic.
One caution on refrigerant choice for the new system. R410A, which dominated for a decade, is itself inside the phase-down, as our post on the R410A phase-out in the UK explains. Most new commercial splits and VRF are now on R32. The installation cost picture depends on whether the existing pipework and electrics can be reused, and that is worth a proper survey rather than a guess.
Frequently asked questions
Is it illegal to keep running an R22 air conditioning system?
No. The law bans using R22 to service or maintain equipment, not owning or operating it. GOV.UK states you can still use equipment containing an ozone-depleting substance as long as it is not leaking. The moment it leaks or needs work on the refrigerant circuit, though, there is no legal gas to refill it with, which is why a refrigerant-side fault ends the system.
Can I still get R22 refrigerant anywhere in the UK?
Not legally for servicing. Virgin R22 was banned for maintenance and servicing from 1 January 2010, and reclaimed or recycled R22 was permitted only until 31 December 2014 under Article 11 of Regulation (EC) No 1005/2009. Since 2015 there is no lawful supply for topping up systems, whatever a van-based seller tells you.
How do I know if my system uses R22 or R407C?
Read the nameplate on the outdoor unit, which states the refrigerant and the factory charge. As a rough age guide, pre-2010 systems are likely R22 unless converted, 2002 to 2010 kit is often R407C, and later plant is R410A or R32. If the system has ever been retrofitted, trust the service records over the plate.
Can an R22 system be converted to run on another gas?
Sometimes. Retrofit blends such as R438A and R422D exist and can work in sound systems, but a conversion usually costs some capacity and asks a 20 year old compressor, expansion valve and seals to work with a gas they were not designed for. It only makes sense on plant that is healthy in every other respect, and it should be assessed on site, not quoted over the phone.
Is R407C being phased out?
There is no ban and no servicing prohibition on R407C as of October 2026. It sits inside the HFC quota, and the step that lands on 1 January 2027 cuts the total HFC supply to the GB market, so high-GWP gases like R407C get scarcer and more expensive ahead of lower-GWP ones. Serviceable today, harder to keep gassed with each passing year.
Should I repair or replace a 20 year old air conditioner?
If the fault is electrical, repair it, because those parts are cheap relative to the system and the gas never moves. If the fault is on the refrigerant side of an R22 system, replace. On R407C it depends on the compressor, the pipework and how many leaks you have already chased this year, which is what the table above is for.
Getting a straight answer on an old system
The uncomfortable truth about 15 to 25 year old air conditioning is that nobody can tell you what to do with it from a desk. The nameplate, the leak history, the state of the pipework and the condition of the compressor decide it, and two identical systems in different buildings regularly get different answers from us.
What we will not do is sell you a conversion on a system that is already dying, or a replacement for a fan motor fault. If you have an R22 or R407C system and you are not sure what you are looking at, book a diagnosis through our air conditioning repair team and we will tell you plainly which row of the table you are in. And if the answer is replacement, our commercial air conditioning installation engineers will scope what can be reused before anyone quotes you a thing.
About the author: Ali Elm runs Be Cool Refrigeration & Air Conditioning, a family-run London firm that has been installing, servicing and repairing commercial refrigeration and air conditioning since 2004. His F-Gas certified team has delivered more than 2,000 projects across London and the South East.
Last updated: 1 October 2026
Written by
Ali Elm
Ali is the Head of Operations at Be Cool Refrigeration with over a decade of hands-on experience in HVAC and commercial refrigeration. He oversees every installation, repair, and maintenance project, making sure the work meets the highest standards. Ali holds full F-Gas certification and has worked across residential, commercial, and industrial refrigeration systems throughout London and the South East. When he is not on site, he writes these guides to help business owners and homeowners understand their cooling systems better.