Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Compressor HVAC: Testing and Inspection

Excessive noise that occurs when the air-conditioning is being used may be caused by:
- Loose Bolts
- Mounting Brackets
- Loose Compressor Clutch
- Excessive High Refrigerant Operating Pressure

Verify the following before compressor repair is performed:
1. Compressor drive belt condition
2. Proper refrigerant charge
3. Thermal expansion valve (TXV) operating correctly
4. Head pressure is normal