Instruction Manual

Caterpillar: Non-Confidential
4. Compressor does not work. When the
engine speed varies, only slight changes are
observed between low and high-pressure
readings
5. Cooling system lines are broken, or
refrigerant is leaking, Low and high pressure
readings are zero
6. Dryer of the receiver or expansion valve is
blocked
4. Repair or replace with the compressor
valve plate
5. Repair cooling system lines, inspect
system for leakage, evacuate lines, and fill
with Freon
6. Disassemble, repair or replace
Insufficient cooling air volume
1. Insufficient volume of air in the vent duct,
air leakage in the vent duct
2. Blower motor does not function properly
3. Compressor electromagnetic clutch slips
4. Compressor efficiency decreases
5. Air exists in the cooling system,
excessively high pressure shown in the high
pressure gauge, misty/murky substances
seen in the sight glass
6. Insufficient refrigerant, bubbles can be
seen in the sight glass, excessively high
pressure shown in the high pressure gauge
7. Insufficient air circulation around the
radiator, excessively high pressure shown in
the high pressure gauge
1. Clean or replace the air filter screen,
clear off obstructions in the vent duct,
reconnect the vent duct
2. Repair or replace the blower motor
3. Repair or replace the electromagnetic
clutch
4. Repair or replace the compressor
5. Bleed air, evacuate the lines, and fill with
Freon
6. Add refrigerant until the bubbles
disappear
7. Clean the radiator and engine water
tank, or install a condensation fan
Cooling system working intermittingly
1. Controllers for idle running and
temperature are out of control
2. Compressor electromagnetic clutch slips
3. Electromagnetic clutch coil is loose or
not grounded well
4. Water in the cooling system causes an
intermittent blocking of the expansion valve
1. Re-adjust or repair
2. Disassemble the bracket or replace
3. Disassemble, repair or replace
4. Replace the dryer of the receiver