LG Electronics LCN240CP service manual Cycle Troubleshooting Guide, Trouble analysis

Troubleshooting Guide

Troubleshooting Guide

CycleTroubleshooting Guide

Trouble analysis

1. Check temperature difference between intake and discharge air, and operating current.

Temp. Difference

Operating Current

Temp. difference	: approx. 0°C(0°F)	All amount of refrigerant leaked out.
Current	: less than 80% of
		Check refrigeration cycle.
	rated current
		Refrigerant leakage
Temp. difference	: approx. 8°C(14.4°F)
Current	: less than 80% of	Clog of refrigeration cycle
	rated current	Defective compressor
Temp. difference	: less than 8°C(14.4°F)	Excessive amount of refrigerant
Current	: near the rated cur-
	rent

Temp. difference : over 8°C(14.4°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	(Compared with	Cause of Trouble	Description
the normal value)	the normal value)
	High	Defective compressor	Current is low.
Higher
	Normal	Excessive amount of	High pressure does not quickly
		refrigerant	rise at the beginning of operation.
		Insufficient amount of	Current is low.
Lower	Higher	refrigerant(Leakage)
		Clogging

Notice:

1.The suction pressure is usually 4.5~6.0 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.

32Ceiling Cassette Air Conditioner