Refrigerant Excessively Low.

Refrigerant Excessively Low.

Complaint.

Cooling is not adequate.

Condition.

1. The low side gauge is reading very low.
2. The high side gauge reading very low.
3. No bubbles or liquid evident in the sight glass.
4. The discharge air from the evaporator is warm.

Diagnosis.

System refrigerant excessively low. Serious leak indicated.

Correction.

1. Test the system for leaks.
   Note: Partially recharge the system before testing the system for leaks to ensure that leak detection is obtained.
2. Depressurise the system.
3. Repair the leaks, and if necessary renew hoses or units.
4. Check the compressor oil level. The system may have lost oil due to leakage.
5. Evacuate the system using a vacuum pump.
6. Recharge the system with new refrigerant.
7. performance.

Air In The System.

Complaint.

Cooling is not adequate.

Condition.

1. The low side gauge reading is constant and does not drop. The pressure should drop until the compressor cycles (thermostat control)
2. The high side gauge reading is slightly high (or slightly lower especially if a large fan is used to substitute ram air).
3. The sight glass is free of bubbles or only shows an occasional bubble.
4. The discharge air from the evaporator is only slightly cool.

Diagnosis.

Non condensables present in the system. Air or moisture present instead of a full refrigerant charge.

Correction.

1. Test the system for leaks. Test the compressor seal area very carefully.
2. Depressurise the system. Repair the leaks, and if necessary renew hoses or units.
3. Renew the drier bottle, probably water saturated .
4. Check the compressor oil level.
5. Evacuate the system using a vacuum pump.
6. Recharge the system with new refrigerant.
7. Operate the system and check the performance.