HVAC Preliminary Checks

HVAC Preliminary Checks

If you suspect a problem in the refrigerant system, inspect for the following conditions:

1. Inspect the outer surfaces of the radiator and the condenser cores to be sure that the airflow is not blocked by dirt, leaves, or other foreign material. Inspect between the condenser and the radiator, as well as all outer surfaces.
2. Inspect for restrictions or kinks in the condenser core, the hoses, and the tubes.
3. Inspect the operation of the blower fan.
4. Inspect all the air ducts for leaks or restrictions. A low airflow rate may indicate a restricted evaporator core.
5. Inspect for slippage of the compressor clutch.
6. Inspect the tension on the serpentine accessory drive belt.

Insufficient Cooling - Quick Check Procedure

Perform the following hand-feel procedure to get a quick idea of whether the air conditioning (A/C) system has the proper charge of Refrigerant-134a. The air temperature must be above 21°C (70°F) for most models.

1. Warm up engine. Run the engine at idle.
2. Open the hood and all the doors.
3. Turn the A/C switch ON.
4. Set the temperature control to the full cold position.
5. Set the blower speed switch on 4.
6. Hand-feel the temperature of the evaporator outlet pipe. The pipe should be cold.
7. Inspect for other problems. Refer to HVAC Preliminary Checks.
8. Leak check the system. Refer to Leak Testing (Component Tests and General Diagnostics). If you find a leak, discharge the system and repair the leak as required. After completing the repair, evacuate and charge the system.