Keeping your cool: why it’s important to check on your car's air con

We’re well into spring and heading for summer – which means your car’s air conditioning button is increasingly more likely to be in the ‘on’ position than the ‘off’. But have you ignored this cool piece of equipment over the winter?

It was once a top luxury feature found on only the most expensive of cars, but today air conditioning is a standard piece of kit on all but the most basic of models. You barely have to check it’s there if buying a used car, thanks to the popularity and demand for this brilliant technology. It’s even a standard listing on most vans and trucks these days.

But although it serves you well during the hot months of summer, keeping temperatures down and comfort levels up, many drivers take that a/c switch for granted and, when it’s not needed, they never give it a second thought.

Bad move. When an air con unit is switched off and forgotten over winter, that’s when problems can arise, so you need to check your car's air con. They need to be used regularly, or they can break down and, as they’re not especially cheap to repair, you could end up with an unwanted bill that’ll leave you hot under the collar.

So it’s a good idea to let yours run for at least 10 minutes every week – even in the middle of winter. And, as they are just as good at helping to defrost a windscreen on a cold, crisp morning as they are cooling the cabin down in the middle of a heatwave, there’s really no excuse not to do this.

What is an air con?

As we move into the summer season where you’ll be using your a/c more, now is the time to check your air con and think about getting it serviced.

Few motorists really know what air con is or how it works. They’re technical pieces of kit – a compressor pumps refrigerant gas to a condenser which turns it into a cold liquid. From here it passes to a drier and then to an expansion valve which allows the driver to control the temperature of the car.

The liquid then turns to vapour as it passes through an evaporator and is blown into the cabin. Now, with the refrigerant back in a gas form it returns to the compressor to start all over again.

That’s why, to work well, this complex system needs to be used regularly. It will help to keep the gas pressure up and will allow working parts to keep moving, thereby reducing the risk of something seizing or failing.

Risk with non use

Idle air con units can also suffer from a build-up of mildew from moisture that has been allowed to collect. This can eventually start to give off stale or unpleasant smells, and you’ll be letting less fresh air into your cabin.

It pays to keep the interior of your car clean. The air conditioning system will pick up dirt and debris and suck it in, leaving bacteria and germs lurking in the inner workings. This is another reason for those bad odours when the a/c unit is turned on for the first time in months.

Some air conditioning recharge services will include a de-bug option which will help to get rid of the smells and freshen the system up.

Important tip

The refrigerant is important and needs to be charged as it will diminish and escape over time. If this happens, the unit will have to work harder to cool the air and this extra work uses more fuel as the system draws power from the engine.

The refrigerant also keeps the compressor cool while it’s at work. If there’s not enough refrigerant, the compressor could overheat and will need replacing.

Your car’s service schedule or manual will tell you when you should have your air conditioning checked and recharged and it’s well worth following this advice.

Because if something fails on your a/c system just when you need it, it’s you who’s going to be left hot and bothered…