my Volvo XC90 makes a hissing noise when I turn on the AC, what's wrong

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to prevent electrical shorts.
• Ensure the engine is off and the AC system is not pressurized.

2. Recover Refrigerant

• Attach a refrigerant recovery machine to the AC system.
• Follow the machine's instructions to safely recover the refrigerant and store it properly.

3. Inspect and Replace Components

• Inspect AC Components:
  • Check the compressor, hoses, and connections for wear or damage.
• Replace Leaking Components:
  • If a leak is detected in any AC component:
    1. Remove the faulty component (compressor, hoses, or expansion valve).
    2. Install the new component, ensuring all connections are tight and using new O-rings where applicable.

4. Recharge AC System

• Using the manifold gauge set:
  • Vacuum the AC system for at least 30 minutes to remove moisture.
  • Recharge the system with the correct type and amount of refrigerant according to the manufacturer’s specifications.

5. Final Inspection

• Reconnect the battery.
• Start the engine and turn on the AC to check for proper operation and listen for any hissing noises.
• Monitor the system for any leaks using a UV dye if necessary.