As soon as the first hot days arrive, I start hearing the same question: "Kris, can you regas my air con?" Of course we can, but my first question is always: "Why has it lost its refrigerant?" You see, your air conditioning is a sealed system. If it's running out of refrigerant every summer, there's a leak somewhere. A proper car air conditioning service means finding out what's wrong, not just topping it up. Otherwise, it's like pouring water into a bucket with a hole in it. It'll leak out again. So what's the point?
Car air conditioning service or just a regas – what's the difference?
With a basic "regas", someone connects a bottle, adds refrigerant until the air starts blowing cold, and calls it a day. But how much refrigerant was in there to begin with? How much did they add? Is there a leak? Is there enough oil? Nobody knows. Yes, you'll get cold air. Maybe for two weeks, maybe for two months. Then you're right back where you started.
When we service your air conditioning, we do it properly. We connect the machine, recover all the refrigerant and measure how much was in the system. That tells us how much is missing. Then we pull a vacuum and check whether the system holds it. If it doesn't, we look for the leak instead of simply filling it up again. Finally, we add oil and recharge the system with exactly the number of grams of refrigerant specified on the label under the bonnet. Not a gram more, not a gram less.
Why is the oil in your air conditioning so important?
Your air conditioning compressor needs lubrication, just like your engine. The oil circulates with the refrigerant, and when refrigerant leaks out, some oil escapes with it. If you just top up the gas every year and forget about the oil, the compressor gradually loses its lubrication. First, it starts making noise. Then it seizes. And that's when you're paying for a new compressor and a complete system clean-out. That can cost many times more than a yearly service.
If your air conditioning runs out of refrigerant every year, please don't keep regassing it blindly. Find the leak and get it fixed. I'm telling you this because otherwise you'll keep paying for a regas every summer, and eventually you might end up paying for a new compressor too.
What else do we do during an air conditioning service?
- Replace the receiver-drier – every spring. It absorbs moisture in the system and helps protect the compressor.
- Clean and disinfect the evaporator. Moisture collects there, creating the perfect conditions for bacteria and mould.
- Change the oil in the system. It protects the compressor from wear. Without proper lubrication, even a brand-new compressor won't last long.
- Check how cold the air is coming out of the vents and measure the system pressure. That tells us whether your air conditioning is working as it should.
Why does your air con smell like wet socks?
I bet you've experienced this one. You switch on the air con and, within seconds, there's that sour smell, as if someone's left a pair of wet socks under the seat. The culprit is the evaporator. It gets cold, moisture collects on it, and dust and bacteria build up there. You can put an air freshener in the car, but that'll only hide the smell. The cause is still there. You need to clean the evaporator and replace the cabin filter. Once that's done, an air freshener actually makes sense.
How can you look after your air con between services?
- Run the air conditioning for a little while during winter too. It helps keep the seals lubricated and makes the air inside the car drier.
- A few minutes before you park, switch off the cooling but leave the fan running. This helps the evaporator dry out so it doesn't start smelling.
- Don't aim freezing-cold air straight at your face. The car will cool down in minutes, but you could end up feeling ill for a whole week.
A tip from Kris Mladenov: I recommend servicing your air conditioning every spring, before the hot weather arrives. I've said the same thing in my Audi A4 B8 service schedule. Half an hour's work could save you a lot of trouble with the compressor, and you'll have clean air inside the car too.
I want you to enjoy a cool, comfortable drive this summer, without any nasty surprises. If this article has helped you, send it to a friend too. You might save them from paying for another unnecessary regas.
What you'll find in our shop
Audi air freshener with replaceable refill – Design fragrance dispenser – Platinum Grey
Audi air freshener with a replaceable refill. Use it after you've cleaned your air conditioning. Not instead of cleaning it.
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Audi air freshener with replaceable refills – yellow
Audi air freshener with replaceable refills in yellow. A light, subtle fragrance that suits any Audi model.
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Genuine Audi interior plastic cleaning and polishing spray 500 ml
Genuine Audi spray for cleaning the plastic trim inside your car, including the areas around the air conditioning vents.
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Frequently asked questions
Why does my car's air conditioning lose refrigerant?
Your air conditioning is a sealed system and should normally lose very little refrigerant. If you need a top-up every year, my friend, there's a leak somewhere. Find it and fix it rather than paying for another regas.
How often should I service my car's air conditioning?
Once a year, ideally in spring, before the summer heat arrives.
Why does my car's air conditioning smell bad?
It's usually dust and bacteria building up on the evaporator. Get it cleaned and replace the cabin filter. An air freshener will only cover up the smell, not fix the problem.