How to Regas the Air Conditioning in Your Car

There are just a few things you’ll need before regassing your aircon.

Check your vehicle handbook and find the location of your air conditioning top-up port and check what type of gas is required. The most common is R134a, but it’s always worth checking the manufacturer’s guidelines. The location of the port can vary depending on your car and is often referred to as a low pressure port.

Once you’re under the bonnet and locate your air conditioning top-up port, you should see a plastic cover on a valve that can be unscrewed. Connect up your dispensing valve and take a reading of your current air conditioning pressure. The dispensing valve will normally have three coloured sections; white showing 0-25 psi, green for between 25-55 psi, and red for 55-150. If your gauge is showing less than 25 psi, your air conditioning would benefit from regassing.

Return to the driver’s seat and start your engine. Turn on the air conditioning to its coldest setting. Make sure to let it run for at least three minutes so that it has time to reach its full operating ability before going under the bonnet to dispense your aircon gas.

Be sure to wear safety glasses before dispensing the aircon gas to protect yourself from any spray or leakage. The gas canister can be very cold, so wear suitable gloves before handling it. Remember to also check any instructions on the can.

First, shake the gas canister to ensure the mixture is fully combined, and then connect it to your dispensing valve by screwing it directly into the head of the measuring valve. To top up your aircon gas, just press the trigger on the dispensing valve for a few seconds. When you let go of the trigger, you will see an updated reading of the refrigerant gas pressure in the system. Continue this process until your reading is in the green and above 25 psi.

If you find your readings are not holding, not improving, or that pressure is falling, it could mean that you have a leak in your system.

It’s best practice to turn off your engine before disconnecting your dispensing valve and replacing your plastic valve cap. This is to ensure your safety when working in the area of the engine.

Try your air conditioning unit again and you should find it blows a lot colder than before. If you don’t experience colder temperatures when your system is fully running, this could be a sign of a leak in your air conditioning system. It’s worth getting this professionally checked by a mechanic before attempting to regas your aircon again.

To maintain the tip-top performance of your air conditioning, you should look to regas your system every two years. With our simple how-to steps, you can easily carry out your own aircon recharge at home. If you’re at all unsure about taking this on yourself, get in touch with a trusted mechanic, and they can perform the air con regas for you.