R134a vs R1234yf: Which Gas Does Your Car Use?

One of the first questions we ask when a car comes in for a regas is which refrigerant gas it uses. It’s not a formality — the two gases in common use aren’t interchangeable, and using the wrong one can damage the system.

R134a — the older standard

R134a has been the standard refrigerant in cars for decades. If your car was built before roughly 2017, there’s a good chance it runs on R134a. It’s a well-understood gas, widely available, and generally the more affordable of the two to buy in bulk.

R1234yf — the newer, greener gas

From around 2017 onward, manufacturers moved to R1234yf across most new vehicles, driven by EU regulations aimed at refrigerants with a lower environmental impact. R1234yf has a much lower global warming potential than R134a, but it’s more expensive to produce, which is reflected in the cost of a regas.

How to tell which one your car uses

The quickest way is to check the sticker under the bonnet, usually on or near the air con compressor or in the engine bay — it will state the refrigerant type directly. If you’re not sure, give us a call with your registration and we can usually confirm it before you even arrive.

Why it matters

Topping up an R1234yf system with R134a (or vice versa) isn’t just ineffective — it can cause real damage to seals, hoses and the compressor, since the two gases behave differently under pressure and aren’t chemically compatible. Always confirm which gas your car takes before any work is done, and be wary of anyone who doesn’t ask.

Whichever gas your car takes, our regas and recharge service covers both, with the correct gas and oil used every time.