How to Stop Refrigerant Gas Leaks in an Air Conditioning Compressor

Repairman working on an air conditioner
What You'll Need
Gas leak detector
Refrigerant pump
Refrigerant coolant
Valve replacement
Soldering materials

If your air conditioning unit has stopped cooling properly, you may need to check your air conditioning compressor for coolant gas leaks. These gas leaks can diminish the amount of coolant your unit has and therefore lower its cooling capabilities. When your unit stops cooling, be certain the cause is a coolant leak because other issues could cause your problems as well. Once you have determined that your issue is a refrigerant gas leak, you should never just refill the coolant without first finding and repairing the leak. Otherwise, you will continually need to add more coolant and not correct the underlying cause of the leak.

Step 1 - Locate the Leak

The best and most definitive way to determine exactly where your refrigerant leak is occurring is to use a gas leak detector. The recommended detector for this project is a halogen-gas leak detector. This type of detector will specifically detect the leak of a halogen gas such as refrigerant coolant. Use the detector to locate the exact leak of the gas, which will be the location where you need to make your repair.

Step 2 - Remove Refrigerant

Before you can begin repair work on your unit, you need to remove all refrigerant from the unit. You will need to connect a refrigerant pump to your unit to remove all of the refrigerant coolant. Pump uses and connections vary quite a bit according to manufacturer, so be certain to read and follow the manufacturer’s instructions for the use of the pump.

Step 3 - Fix the Leak

air conditioner compressor


If the leak is found in a valve, you may be able to clean the valve thoroughly and make sure it is properly attached. Try this first and then retest with the gas detector. If the air conditioner leak is still present, you will need to replace the valve. This simple replacement entails removing the existing valve and attaching a new valve in its place.


If the leak exists within the tubing of the unit, you will need to seal the leak. This will require you to solder the line. You will need to use a very high temperature torch and solder with a high silver content for this repair. Visibly inspect the line to see if you can detect the crack or leak. If the leak is small, you can solder the line over the leaking area to repair it. If the leak is large or the crack is large, you will be better off cutting out the damaged area of the line and replacing it with a new piece of pipe that you can solder into place.

Step 4 - Recharge the Coolant

Once the leak has been repaired, you will need to recharge the unit by replacing the refrigerant coolant with new coolant. Make certain you do not add too much coolant. Over adding coolant will not improve the performance of your unit, but rather hinder the performance. Air conditioning units will function best when the exact amount of required coolant is added according to the manufacturer’s instructions.