LG LAN121CNM Service Manual - Page 49

Troubleshooting Guide Cycle Parts Trouble analysis 1. Check temperature difference between intake and discharge air and operating current. Temp. difference : approx. °F(0°C) Current : less than 80% of rated current • All amount of refrigerant leaked out. Check refrigeration cycle. Temp. Difference Temp. difference : approx. 14°F(8°C) Current : less than 80% of rated current • Refrigerant leakege Clog of refrigeration cycle Defective compressor Operating Current Temp. difference : less than 14°F(8°C) Current : over the reated current • Excessive amount of refrigerant Temp. difference : over 14°F(8°C) • Normal 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. Suction pressure (Compared with the normal value) Higher Temperature (Compared with the normal valve) High Normal Cause of Trouble Defective compressor Defective 4-way reverse valve Excessive amount of refrigerant Lower Higher Insufficient amount of refrigerant (Leakage) Clogging Description Current is low. High pressure does not quickly rise at the beginning of operation. Current is low. Current is low. NOTICE 1. The suction pressure is usually 8.5~9.5 kg/cm2G(Cooling) at normal condition. 2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with putty. Service Manual 49