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When do I need to recharge my car’s air conditioning system?

Feeling the heat recently? The increase in temperature sweeping the UK right now has not only resulted in sunnier, warmer days, but also the uncomfortable sensation of turning on your car's air conditioning unit only to be blasted with hot air.
If you've experienced this, your car air conditioning system needs recharging. Don't worry if you don't understand how it works - this blog post covers all the basics.

How does my car’s air conditioning system work?

Your car’s air conditioning system is a lot more complicated than you might expect. Contrary to popular belief, your car’s A/C system does not actually create cold air. Instead, it takes the heat and moisture out of air that is already in the car, which leaves behind cooler air.

The system requires a refrigerant (the gas which needs to be refilled regularly for it to function). When you switch on your car’s A/C, the refrigerant is pumped towards a condenser, where it liquefies as the temperature drops. Air from outside of the vehicle passes over the condenser.

The outside air, in liquid form at this point, passes through a drier which removes any impurities. It then travels towards a thermal expansion valve where liquid flow can vary – this is the part of the air conditioning system that you as the driver can control using the temperature dial on your dashboard.

The liquid travels through evaporation coils and turns into vapour, after which it is blown into the cabin as cool air. The refrigerant returns to its original gas form and returns to the compressor.

Because changes of state require energy loss, over time the refrigerant is used up – this is why it’s crucial to have your air conditioning system recharged regularly.

Why do I need to recharge my car’s air conditioning system?

The most obvious reason for recharging your car’s air conditioning system is to keep both you and your passengers cool on hotter days.

However, having a fully charged air conditioning system in your vehicle is beneficial for a few additional reasons, including:

  • Increased fuel efficiency – a full tank of refrigerant means the air con system is able to easily cool the air inside your vehicle. When it starts running low, the system has to work harder to lower the internal temperature of your car, which uses more fuel.
  • Fewer repairs – keeping your refrigerant topped up ensures the compressor within your vehicle’s air conditioning system stays cool. Without enough refrigerant, the compressor is at risk of overheating and failing, resulting in costly repairs.
  • Useful in cold weather – you can switch on the air conditioning system to demist your windscreen during cold weather. This has the added benefit of increasing system usage during the colder months, reducing the chances of it seizing up once summer rolls around again.

Why isn’t recharging my car’s air conditioning system included in my MOT or Service?

Your MOT does not include recharging your car’s air conditioning system. This is because technically, air conditioning does not fall under the MOT remit of checking whether the vehicle is “safe to drive”.

Air con is a luxury feature and is therefore also often left out of standard servicing schedules. You’ll need to book a separate air conditioning recharge and check to make sure your vehicle’s A/C is functioning effectively.

How often should I recharge my car’s air conditioning system?

Most vehicle manufacturers recommend recharging your car’s air conditioning system at least once every two years. Of course, if you use A/C periodically you may find that coming in for an Air Conditioning Recharge and Check once a year might be a better choice for you.

Air Con Recharging from the Auto Care Group

If you need to recharge your car’s air conditioning system, the Auto Care Group has garages in Stockton; Teesdale, and Darlington. You can schedule an Air Conditioning Recharge and Check today on our website – the process takes around 45 minutes and can be completed while you wait.  As well as being able to handle the old Air con gas (R134a) we also have the capability to do the newer gas (HFO-1234yf) for newer vehicles at prices way cheaper than the main dealer.