
- 103 -
Copyright © 2020 LG Electronics Inc.
All rights reserved. Only training and service purposes.
Self-diagnosis function
01 Indoor unit air sensor error
02 Indoor unit pipe inlet sensor error
06 Indoor unit pipe outlet sensor error
Error
No.
Error Type
Error Point
Main Reasons
Indoor unit sensor is
open/short
1. Indoor unit PCB wrong connection
2. Indoor unit PCB failure
3. Sensor problem (main reason)
** In case the value is more than 100 kΩ (open) or less than 100 Ω (short), Error occurs
Refer: Resistance value maybe change according to temperature of temp sensor,
It shows according to criteria of current temperature(±5 % margin)
➔
Normal
Air temp sensor: 10 °C = 20.7 kΩ : 25 °C= 10 kΩ : 50 °C= 3.4 kΩ
Pipe temp sensor: 10 °C = 10 kΩ : 25 °C= 5 kΩ : 50 °C= 1.8 kΩ
n
Error diagnosis and countermeasure flow chart
Is sensor properly
connected to PCB?
Is the resistance value
of sensor normal?*
Connect properly to PCB
Change the sensor
Change the PCB
Yes
Yes
No
No
CN-ROOM : Indoor air temp sensor
CN-PIPE IN : Pipe inlet temp sensor
CN-PIPE OUT : Pipe outlet temp sensor
Measure the resistance of outlet pipe temp sensor.