Compressor Malfunction

Compressor Malfunction

Complaint.

Cooling is not adequate.

Condition

1. The low side gauge reading is too high.
2. The high gauge reading is too low.
3. The sight glass is free of bubbles and the system is fully charged.
4. The discharge air from the evaporator is not sufficiently cool.

Diagnosis.

Internal leak in the compressor.

Correction.

1. Depressurise the system.
2. Renew the compressor and the drier bottle.
3. Evacuate the system using a vacuum pump.
4. Charge the system with new refrigerant.
5. Operate the system and check the performance.

Condenser Malfunction or System Overcharge

Complaint.

Little or no cooling. Overheating of the engine may also be noted.

Condition.

1. The low side gauge reading excessively high.
2. The high side gauge reading is also excessively high.
3. Bubbles may appear occasionally in the sight glass and the liquid line to the evaporator is very hot.
4. The discharge air from the evaporator is warm.

Diagnosis.

The condenser not operating correctly through lack of cooling caused by too high a high side pressure. The system may have either a normal or overcharge of refrigerant.

Correction.

1. Check the compressor drive belt for correct tension.
2. Check the condenser for clogged air passages preventing air flow through the condenser.
3. Inspect the condenser mounting for correct radiator clearance.
4. Check for correct fan operation.
5. Check the coolant pressure cap for correct type and operation.