LG multi V PLUS, Service Manual

Page: 274 / 373

274 Trouble Shooting Guide
Self-diagnosis function
Fault diagnosis and Trouble shooting guide
35
144
146
Error Item
Error
Display No.
Major Error Occurrence Cause Meaning
35: Low pressure drop of
main outdoor unit
144: Low pressure drop
of Sub1 outdoor unit
144: Low pressure drop
of Sub2 outdoor unit Compressor stops by
excessive drop of low
pressure
• Failure of low pressure sensor or low
pressure sensor detection circuit part
• Clogging of service valve
• Insufficient refrigerant
• Leakage of refrigerant
• Poor indoor pipe temperature sensor
• Failure of indoor/outdoor unit fan
• Check communication lines of indoor units.
• Check LEV connection of indoor unit PCB.
Trouble shooting Flow
No No
Replace the PCB.
Yes
Yes
Replace the low
pressure sensor.
Is suction pressure (low pressure)
actually high?
Is the pressure sensor normal?
No
Check the outdoor/indoor LEV.
Yes
Modify wiring.
Check or replace the fan.
Is the LEV of the indoor/outdoor
unit normal?
Are communication lines normal?
No
No
Yes
Yes
Is the fan of the indoor/outdoor
unit normal?
Check open status of the service valve.
Check clogging of pipe or status of refrigerant.