Air Conditioner
LG
Updated Jul 22, 2026
LG AC CH45 Error — Condenser Coil Outlet Sensor Fault & Fix
CH45
LG · Air ConditionerCH45 means the condenser coil outlet temperature sensor (thermistor) on the outdoor unit h…
Quick answer
CH45 means the condenser coil outlet temperature sensor (thermistor) on the outdoor unit has an open or short circuit.
What CH45 means
The condenser outlet sensor monitors the temperature of the liquid refrigerant leaving the outdoor coil. The board uses this for subcooling calculations and to control the expansion valve. Without it, efficient refrigerant flow control is impossible.
How to fix it
What does the CH45 code mean?
CH45 is a condenser coil outlet temperature sensor fault (open or short circuit) on the outdoor unit.
Common causes
- Faulty condenser outlet thermistor
- Loose connector on the outdoor PCB
- Wire corrosion or damage
- PCB fault (rare)
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How to fix the CH45 error
Power off
Isolate at the breaker.
Find the sensor
Clipped to the liquid line (smaller pipe) exiting the outdoor coil.
Reseat connector
Check and re-plug at the outdoor PCB.
Test with multimeter
Replace if reading is open or zero.
Replace and secure
Clip firmly to the pipe for accurate readings.
Safety first: The outdoor unit contains high-voltage components. Isolate power completely.
Part you may need: Condenser outlet temperature sensor (NTC thermistor)
This sensor is sometimes located near the filter drier — check your model's service manual for exact location.
Frequently asked questions
Is CH45 serious?
The AC may run but with poor efficiency and incorrect expansion valve control. Fix it promptly.
Can a dirty condenser cause CH45?
No — CH45 is an electrical sensor fault. A dirty condenser causes high pressure (different error).
✎ Written by
REZAUL Karim (Riad)
REZAUL Karim (Riad) is the founder of ErrFixHub and a hands-on electronics and home-appliance repair specialist with over 15 years of experience diagnosing and fixing air conditioners, washing machines, refrigerators, inverters and other household appliances. He built ErrFixHub to turn cryptic error codes into clear, step-by-step fixes anyone can follow — cross-checking every code against manufacturer documentation and real repair-bench experience.
