Air conditioning service and regas

Which gas does my car use, R134a or R1234YF?

There is a label under the bonnet that tells you, usually on the slam panel or near the strut tops, and it names the refrigerant and the charge weight. As a rough guide, cars first registered from around 2017 use R1234YF and older ones use R134a, but the changeover ran over several years and the only answer that matters is the one on your car.

The reason for the change was environmental rather than technical. A European directive set a limit on the global warming potential of refrigerant in newly approved cars from 2011, and R134a is far above it. R1234YF sits far below. Manufacturers moved across model by model, which is why two cars of the same age can take different gas, and why guessing from the registration year is not good enough.

Send us the registration and we will tell you which one it takes.

Why do some garages only do the old gas?

Because R1234YF needs its own equipment and the equipment is expensive. The newer gas is classified A2L, which means mildly flammable, where R134a is A1 and is not. That one classification changes everything downstream: the recovery and charging station has to be A2L-rated, the vacuum pump has to be A2L-compliant, and the leak detector has to be specific to the gas. None of it is shared with the old kit, and a garage cannot put R1234YF through an R134a machine.

The gas itself is the other half of it. R1234YF costs in the region of ten times more per gram than R134a. That is most of the difference between the two jobs, and it is why a price advertised for "an air con regas" with no mention of which gas is a price for the cheaper one.

We run both. That is the whole point of this page.

Can R134a just be put into an R1234YF system?

No. The service ports are deliberately different sizes so the two cannot be connected by accident, the oils are different, and doing it anyway risks the compressor and leaves the car with a refrigerant it was never designed around. It also has to be recovered and the system properly recharged before anybody can work on it honestly, which costs more than doing it right in the first place.

If somebody has quoted you an R134a price for a car that takes R1234YF, that is the thing to check before anything else.

My air conditioning is not cold. Does it just need a regas?

Maybe, but a system that has lost its charge has lost it somewhere, because refrigerant is not consumed. A small annual loss through seals and hoses is normal and is what the two-yearly recharge exists for. A system that was cold last month and is warm today has a leak, and putting gas into it without finding the leak is paying to fill the atmosphere.

So the order of work is diagnosis first. What we are looking for:

• A leak, most often at the condenser, which sits at the front of the car behind the grille and takes stone chips and road salt for a living
• A leak at a pipe union, a seal or the compressor shaft seal, which is what a dye or an electronic detector is for
• A compressor that is not engaging, which can be the compressor itself or can be a pressure switch, a relay or a control fault telling it not to
• A blocked pollen filter or a blocked condenser, where the gas is fine and the airflow is not
• A smell rather than a temperature problem, which is usually bacteria and mould on a wet evaporator and is cleaned rather than regassed

Then recovery, a vacuum and a hold test to prove the system is tight, a recharge by weight to the figure on the label, and a performance check on the vent temperature. If the car does not need the work, we will say so.

Does air conditioning matter on an electric car?

More than on a combustion car, and this is the part owners are rarely told. On many electric and plug-in hybrid models the same refrigerant circuit that cools the cabin also cools the drive battery, through a component called a chiller. The air conditioning is not a comfort feature bolted onto the side of the car, it is part of the battery's thermal management.

Which means a refrigerant fault on an EV is not only a warm cabin. It can show up as reduced rapid charging speed, as reduced performance when the battery is warm, or as a warning the owner reads as a battery problem. Electric cars also use R1234YF almost universally, so this is exactly the overlap where a garage needs both the gas equipment and the high-voltage training, and we have both.

More on EV and plug-in hybrid work.

When is the best time to have it done?

Spring, and for two practical reasons. Garages are not yet in the summer rush, and you find out the system works before the week you actually need it rather than during it.

There is also a technical reason not to leave it to the first cold snap of autumn: a recharge cannot be measured accurately when the ambient temperature is down around five degrees, because the system will not reach the pressures the readings depend on. If you bring it in on a cold morning we may ask you to leave it with us until the day warms up, which is a better answer than a charge we cannot stand behind.

One more thing worth knowing: running the air conditioning for ten minutes every few weeks through the winter keeps the compressor seals lubricated. Most of the systems that have lost their gas lost it over a winter of never being switched on.

Where are you, and how do I book?

We are at Unit B2, Fram Enterprise Centre, Heol-Y-Sarn, Edwards Business Parc, CF72 8QZ, a few minutes from Talbot Green and Llantrisant and a straightforward run from Cardiff, Pontypridd and Bridgend. Call or WhatsApp with the registration and we will tell you which gas it takes before you come in.