why does my Alfa Romeo Giulia 952 (2016-Present) AC blow warm air after 10 minutes?

Symptoms

• AC system blows warm air after 10 minutes.
• Reduced airflow from AC vents.
• Unusual noises from the AC compressor when engaged.
• Moisture or water pooling under the vehicle.
• AC compressor clutch not engaging or disengaging properly.

Diagnostic Steps

1. Check the refrigerant level using a manifold gauge set to ensure it is within the manufacturer's specifications.
2. Inspect the AC compressor for signs of wear or damage, including checking the clutch operation.
3. Look for any visible leaks in the AC system, including hoses and fittings.
4. Test the AC pressure switches and relay with a multimeter to confirm they are functioning correctly.
5. Examine the cabin air filter to ensure it is clean and not obstructing airflow.
6. Verify the operation of the blend door actuator for proper temperature control.

Solution

1. Preparation

• Gather tools and components needed for the repair.
• Disconnect the battery to ensure safety while working on the electrical components.

2. Recharge Refrigerant

• Tools Required: Manifold gauge set, refrigerant canister, and vacuum pump.
• Using the manifold gauge, connect to the low and high-pressure service ports.
• If the refrigerant level is low, evacuate the system with a vacuum pump for at least 30 minutes to remove moisture.
• Recharge the system with the correct amount of refrigerant as specified in the vehicle's service manual.

3. Inspect and Replace AC Compressor

• Tools Required: Socket set, wrench set, and AC compressor replacement.
• Remove the serpentine belt by loosening the tensioner pulley.
• Disconnect the AC lines from the compressor and unbolt the compressor from its mounting.
• Install the new compressor and reconnect the AC lines, ensuring O-rings are replaced to prevent leaks.
• Reinstall the serpentine belt, ensuring it is properly routed and tensioned.

4. Replace Cabin Air Filter

• Tools Required: None (manual may suggest specific tools).
• Locate the cabin air filter compartment, usually behind the glove box.
• Remove the glove box or cover to access the filter.
• Replace the old filter with a new one, ensuring it is oriented correctly for airflow.

5. Test AC System

• Tools Required: AC service tool (if applicable).
• Reconnect the battery and start the engine.
• Turn on the AC system to check for proper operation and observe the temperature from vents.
• Monitor for unusual noises or leaks while the system is running.