LG LSC121PMA Service Manual - Page 42

Cycle Troubleshooting Guide 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 All amount of refrigerant leaked out. Check refrigeration cycle. Temp. difference :approx. 8°C(14°F) Current :less than 80% of rated current Refrigerant leakage Clog of refrigeration cycle Defective compressor Temp. difference :less than 8°C(14°F) Current :less than 80% of rated current Excessive amount of refrigerant Temp. difference :over 8°C(14°F) 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. Suction pressure Temperature (Compared with the (Compared with the normal value) normal value) Cause of Trouble Description Higher High Normal Defective compressor Defective 4-way reversing valve Current is low. Excessive amount of refrigerant High pressure does not quickly rise at the beginning of operation. Lower Higher Insufficient amount of refrigerant(Leakage) Clogging Current is low. Current is low. Notice: 1. The suction pressure is usually 4.5~5.0 kg/cm2G at normal condition. 2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with putty. - 42 -