Cycle Part - LG A2UW18GFA0 Svc Manual

Part 5. Trouble Shooting

5. Cycle Part

Trouble analysis
1. Check temperature difference between intake and discharge air, and check for the operating current too.
Case
Temp. difference : approx. 0°C
Case 1
Current : less than 80% of rated current
Temp. difference : approx. 8°C
Case 2
Current : less than 80% of rated current
Temp. difference : less than 8°C
Case 3
Current : over the rated current
Case 4
Temp. difference : over 8°C
NOTICE
Temperature difference between intake and discharge air depends on room air humidity. When the room air humidity is
relativery 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 in cooling mode.
Suction pressure
Discharge Air (Compared
(Compared with
with the normal valve)
the normal value)
Higher
Lower
NOTICE
1. The suction pressure is usually 8.5~9.5kg/cm2G(Cooling) at normal condition.(R410A)
2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with putty.
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Symptom
Temperature of
Defective compressor
High
Defective 4-way reverse valve
Excessive amount of
Normal refrigerant
Insufficient amount of
Higher refrigerant (Leakage)
Clogging
All amount of refrigerant leaked out.
Check refrigeration cycle.
Refrigerant leakage Clog of refrigeration cycle
Defective Compressor.
Excessive amount of refrigerant
Normal
Cause of Trouble
- 44 -
Supposed Caused
Description
Current is low.
High pressure does not quickly
rise at the beginning of
operation.
Current is low.
LGE Internal Use Only