How to Replace a Car Air Conditioner Compressor

car air compressor
  • 1-6 hours
  • Advanced
  • 100-350
What You'll Need
Shop towels
New compressor
Flush kit
Mechanic gloves

The car air conditioner compressor is the heart of the system. It is a pump that is driven by a belt and found fastened to the engine. The job of the auto air compressor is to compress and transfer coolant gas. The air conditioning system is broken down into two sides; a high pressure side and a low pressure side. The compressor has an intake side that draws in the coolant gas from an outlet on the evaporator, and it has a discharge side through which the coolant is compressed and sent through a condenser that transfers the heat from the inside of the cabin.

Before replacing the air conditioner compressor, familiarize yourself with your car air conditioner system. The condenser cools the freon in the air conditioner system. This should be flushed to remove any debris. This will help to remove any compressor oil that has been contaminated. The accumulator, also referred to as a Receiver Drier, is set in the air conditioner system to trap or remove moisture. It also filters particles and acts as a storage container for compressor oil and coolant. The air conditioner compressor oil is also known as the life blood of the air conditioner system. The compressor is the only component in the air conditioner system that requires oil. It is best to get the compressor oil that does not hold moisture. It is important to remove as much of the contaminated oil as possible. Lastly, the air conditioner hose assemblies. There are three different hoses you should be careful and pay attention to: one from the compressor to the condenser, one from the condenser to the evaporator and one from the evaporator back to the compressor. It is important after removing all hoses, to flush them. This will wipe out any oil and debris.

One of the most expensive repairs known to the air conditioning system is to replace the compressor. When replacing the compressor yourself, it is extremely important that you follow all steps properly, and get a warranty on the new compressor. There are very few steps when it comes to removing a compressor.

Step 1 - Evacuate the Freon

If you are not a licensed Freon handler, then have a licensed Freon handler evacuate the system.

Step 2 - Loosen the Belt

air conditioner control in a car

Loosen the belt, and remove the lines from the compressor.

Step 3 - Remove the Bolts

Remove the bolts holding it on.

Step 4 - Remove the Compressor

Carefully remove the compressor from the bracket. The lines are very thin so take caution when removing it. Be aware of any fluids that may come from the lines as they may cause harm to the skin.

Performing a system flush is cleaning the internal parts of the air conditioner system. It is not advisable to replace the car air conditioner compressor without completing a system flush. Flush system to remove all debris and contaminants that were left in it. Do not, under any circumstances, ever try to flush the compressor itself. Do disconnect each of the system components mentioned above and flush them individually.

Optionally you can add an inline filter to your air conditioner system when you replace your compressor. This filter helps keep any debris left in your system out of the new compressor.

Step 5 - Refill the Freon

Have a licensed Freon handler Refill the system to exact amount for your automobile.