Service Manual 37
1. Trouble analysis
1. Check temperature difference between intake and discharge air and operating current.
Temp. Difference
Operating Current
Temp. difference :approx. 0°F
Current
:less than 80% of
rated current
Temp. difference :approx. 8°C(14°F)
Current
:less than 80% of
rated current
Temp. difference :less than 8°C(14°F)
Current
:less than 80% of
rated current
Temp. difference :over 8°C(14°F)
All amount of refrigerant leaked out.
Check refrigeration cycle.
Refrigerant leakage
Clog of refrigeration cycle
Defective compressor
Excessive amount of refrigerant
Normal
Notice:
Temperature difference between intake and discharge air depends on room air humidity. When the room air
humidity is relatively higher, temperature difference is smaller. When the room air humidity is relatively lower
temperature difference is larger.
2. Check temperature and pressure of refrigeration cycle.
Notice:
1. The suction pressure is usually 4.5~5.0 kg/cm
2
G at normal condition.
2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with
putty.
Suction pressure
(Compared with the
normal value)
Temperature
(Compared with the
normal value)
Cause of Trouble
Description
Higher
High
Defective compressor
Defective 4-way reversing valve
Excessive amount of refrigerant
High pressure does not quickly
rise at the beginning of operation.
Current is low.
Normal
Lower
Higher
Insufficient amount of
refrigerant(Leakage)
Clogging
Current is low.
Current is low.
Troubleshooting Guide
Cycle Parts
