Cycle Part - LG Single "A" Service Manual

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 rela-

tivery 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.

Be sure to disconnect the power cable plug from the plug socket before disassembling the

equipment for a repair. Internal components and circuit boards are at main potential when the

equipment is connected to the power cables. This voltage is extremely dangerous and may

cause death or severe injury if come in contact with it.

Be sure to turn off power switch before connect or disconnect connector, or parts damage may

be occurred.

Copyright ©2008 LG Electronics. Inc. All right reserved.

Only for training and service purposes

Symptom

Temperature of

Cause of Trouble

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

- 83 -

5. Trouble Shooting

Supposed Caused

Description

Current is low.

High pressure does not quickly

rise at the beginning of

operation.

Current is low.

LGE Internal Use Only