Compressor HVAC: Testing and Inspection

- When troubleshooting a noisy compressor complaint, make sure the noise is present only when the clutch is engaged.
- If it is present when the clutch is not engaged, remove the compressor drive belt and check again.
- If the noise continues, it is not related to the compressor.
- If removing the drive belt reduces or eliminates the noise, check the torque of the compressor and bracket mounting bolts.
- Check the belt tension and condition.
- A loose/slipping belt can cause noise.
- A belt that is too tight can damage the clutch bearings.
- If the compressor is noisy with the compressor clutch engaged, make sure the system is charged with the correct amount of refrigerant.
- An over-charged system can cause compressor noise.
- If the compressor is replaced in this case, and the system is charged 'with the correct amount of refrigerant, the technician will incorrectly assume the compressor was at fault.
- If the A/C system is overcharged with refrigerant, the liquid entering the compressor can damage it.
- When troubleshooting a noisy compressor complaint, recover the refrigerant and recharge the system with the correct amount.
- A failed compressor must be returned with the inlet and outlet ports sealed using the plastic caps from the replacement compressor. Otherwise the "failed" compressor will be damaged by moisture, and it will be impossible for Warranty to analyze it.
- For details on compressor replacement, see Air Conditioning Compressor - Service and Repair.