Why recharge your car air con?

01 June 2020 / info@castlegarageashby.com

Is air con part of my MOT or Service?

No, your annual MOT ensures the vehicle is safe to drive as per strict DVSA guidelines. Since air conditioning is considered a ‘nice-to-have’ feature and is not critical to the safe running of the vehicle, your MOT tester will not check to see if your air con is working.

Similarly, air con is not included in the standard service schedule set out by your vehicle manufacturer. Regular servicing will help keep your car running for longer in a safe and reliable condition and includes some replacement parts like the oil and air filters. But those drivers expecting their air con to be recharged as part of their service will be disappointed. Many manufacturers provide a separate air con service schedule which will recommend a regas, on average, every 2 years.

Castle Garage can regas both the new (R1234yf) and old (R134a) style air con gases.

Click here to head to our air con page to book in online

Air con on or window down?

If you’re not sure whether to use the air conditioning or simply wind the window down on a hot day you probably need to be asking yourself “how important is fuel economy to me?” Air con will certainly provide the most comfort on a hot day and the driver has the option to control the temperature and the blowers. Having the window down provides just one uncontrollable setting and it can get quite loud and blustery in the cabin – the faster you go, the worse it gets. Also, when travelling at speed, the vehicle becomes less aerodynamic and experiences ‘drag’ so you’ll be using more fuel to get to your destination. That said, using the air con comes at a price too. The compressor at the heart of your air conditioning system requires energy in order to circulate cold air around the vehicle. It gets the energy from the engine so when the air conditioning system is turned on you will also be using more fuel. So for optimum fuel efficiency, it’s windows down at low speeds, air con on at high speeds.

Why does air con stop working?

The refrigerant, or gas, found in your air conditioning unit is critical to the air con system working properly. It is this refrigerant that flows around the system and provides the cold air in your cabin. However, as a result of this process which involves continually shifting states from gas, to liquid and back to gas again, some of this air con gas permeates through the system each year. Less gas means less cool air so refilling every few years will keep your air con working in tip top condition.

Of course there are other reasons why air con stops working but low refrigerant is the most common and, thankfully, the easiest to fix. If after a regas your air con is still blowing warm, it probably means there is a crack somewhere in the pipes of the air con system and the refrigerant is escaping.

How do you recharge a car’s air con unit?

Recharging the air con system involves removing all of the existing refrigerant and any traces of moisture from the system and replacing with fresh refrigerant.

Using an automatic air con servicing machine, two hoses are attached to the air con system under the bonnet – one to the high pressure port, the other to the low pressure port. Firstly, a pressure test is carried out to find out just how much gas has been lost. If the test result shows that little or no gas remains in the system, this indicates a more serious issue such as a potential leak and the recharge is stopped. If no faults are found, the machine recovers the old refrigerant and any impurities from the air con unit using a specialist vacuum pump. Next, fresh gas and lubricant is injected back into the air con system as per the volume and type recommended by the vehicle manufacturer.

How long does an air con recharge take?

The process take about 45 minutes to completely remove the old gas and refill with fresh refrigerant. At Castle Garage (Ashby) LTD, you can have your air con recharged while you wait and take advantage of our free wifi and hot drinks.

How often should you recharge your air con?

Opinion varies but most vehicle manufacturer’s recommendation is every two years. Whether you use your car’s air con a lot or hardly ever at all, air con gas will continue to permeate through the system over time so an air con service every two years will keep the gas topped up and the system lubricated so you always have a cool blast ready when you need it most.

How quickly does air con take to get to work once recharged?

With the new gas installed, you should be able to notice a temperature change almost immediately when the air conditioning is switched on. The new gas is flowing through the system providing cool air and lots of it

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