How to Replace a Car AC Compressor How to Replace a Car AC Compressor

What You'll Need
New AC compressor for your car
Toolbox including socket wrench set and screwdriver set

If something goes wrong with your car’s air conditioning system, it likely due to a problem with the car AC compressor. This is because the compressor is under far more stress than any other part of the system and thus more prone to breaking down. If the problem with your car AC compressor has been diagnosed to be external, then it may be possible to fix it without having to replace it. However, in the worst case scenario, the problem may be with the internal functions of the system, in which case the unit will need to be replaced. You should also bear in mind that compressor failures are usually a result of the compressor having to deal with much higher pressures due to other components in the system failing.

Step 1 - Handling the Refrigerant

Exposing the refrigerant of your car’s AC compressor is not something you should attempt. This is illegal since it is highly damaging to the environment. First, you will need to identify the type of refrigerant and remove it in accordance with your local laws. You must do this before starting work on replacing the unit.

Step 2 - Removing the Old Compressor

The details of removing the old AC compressor from your car will depend largely on the specific model that you have. Be sure to carefully disconnect all of the brackets, sensors and any switches. After this is done, any components that you will not replace should be flushed using an appropriate AC solvent. This will remove any contamination, which is essential for it to work with the new AC compressor. The system then needs to thoroughly air-dry so that none of the solvent remains in the components.

Step 3 - Replacing the Components

Start by replacing the accumulator and other devices, including the screen and opening tube. Replace the AC compressor as instructed by the guidelines specific to your car and AC compressor model. Be sure that all brackets are properly reattached and that the compressor is mounted and aligned correctly. Do this and double check it before attaching any of the system’s other components to it. It is also advisable to install a filter in the suction line by the compressor inlet. This will help to protect the new AC compressor from dirt getting inside the system and causing damage.

Step 4 - Getting the System Ready for Use

Add the appropriate AC oil to the system as instructed to by the manufacturer of the AC compressor. You will then need to remove any moisture or flushing solids from the system by applying a vacuum to the system. 29 inches of mercury per hour is recommended as a minimum.

Finally, you can recharge the system as instructed by the manufacturer. Test all of the components to make sure that the system is running correctly. Carefully evaluate every component of the system; otherwise, you can run the risk of the expensive disaster of having to replace the AC compressor yet again. 

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