Chapter 8 - Troubleshooting & Service Procedures
After finding a leak, recover all refrigerant from
the system and repair the leak. Check the com-
pressor and replace any refrigeration oil lost due to
leakage. Evacuate and recharge the system with
refrigerant, then check AC operation and perfor-
mance.
Air and/or Moisture in the System
Figure 8-7
Gauge reading, air andlor
moisture in the system.
The sight glass may be clear or show some bubbles.
Tip:
The air from vents in the cab is only slightly cool. In a
cycling clutch type system with a thermostatic
switch, the switch may not cycle the clutch on and off,
so the low pressure gauge will not fluctuate.
Air and/or moisture in the system.
Cause:
Repair Procedure:
Test for leaks, especially around the compressor
shaft seal area. When the leak is found, recover
refrigerant from the system and repair the leak.
Replace the receiver-drier or accumulator because
the desiccant may be saturated with moisture (there
is no way to tell). Check the compressor and replace
any refrigeration oil lost due to leakage. Evacuate
and recharge the system with refrigerant, then check
AC operation and performance.
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