LG aircon thermistor repair in Singapore
A LG temperature-sensor code can point to the thermistor, its connector and wiring, or the PCB input that reads it. We test the thermistor, wiring and PCB input, explain what failed and quote after diagnosis.
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Signs your LG aircon needs a thermistor check
These symptoms can involve a temperature sensor, but they can also come from its wiring, the control board, airflow or the refrigerant circuit.
A temperature-sensor error appears
A LG room, coil, pipe or outdoor sensor code identifies the circuit to test, not automatically the failed part.The unit short cycles or runs continuously
An incorrect temperature signal can make the system stop too early, run longer than expected or struggle to hold the set temperature.The temperature reading or icing looks unusual
A reading that does not match the room, repeated icing or unexpected protection can justify a sensor-circuit check.
Examples of LG systems we check
Dual Inverter S3-Q residential split systems
ArtCool and ArtCool Mirror wall-mounted systems
MU residential multi-split systems; Multi V scope confirmed from the exact model
Model not listed
Send photos of the indoor and outdoor model labels, plus the error code or a short video of the symptom.
It may not be the thermistor
Before ordering a model-specific sensor, we check three problems that can create the same code or temperature behaviour.
Loose connector or damaged wiring
An open, shorted or corroded sensor harness can produce the same reading as a failed thermistor.PCB input fault
The sensor may measure correctly while the control board reads or processes its signal incorrectly.Airflow or refrigerant condition
A restricted coil, icing or abnormal refrigerant condition can create temperature symptoms without a failed sensor.
We match the code to the exact sensor circuit, inspect the connector and harness, measure the thermistor at the current temperature, and verify the PCB input. How a job runs, from first message to booking.
What is different on LG systems
LG sensor faults can sit at the indoor unit, outdoor unit or connected pipe circuit. We test the named sensor and wiring before treating the thermistor as failed.
LG error codes related to thermistor problems
Open the group that matches where the code appeared on your unit.
Indoor unit or controller9 guides
- CH01Indoor unit room temperature sensor error; Indoor unit return air thermistor disconnected or shorted
- CH02Indoor unit inlet pipe sensor error; Indoor unit inlet pipe thermistor disconnected or shorted
- CH06Indoor unit outlet pipe sensor error; Indoor unit outlet pipe thermistor disconnected or shorted
- CH08indoor unit: Hydro-kit hot-water storage-tank temperature sensor error
- CH13indoor unit: Hydro-kit solar heat-pipe temperature sensor error
- CH16indoor unit: Hydro-kit water-pipe and ambient-temperature sensor communication error
- CH17indoor unit: Hydro-kit inlet-pipe or outside-air duct inlet-pipe temperature sensor error
- CH18indoor unit: Hydro-kit outlet-pipe temperature sensor communication error
- CH230indoor unit: Refrigerant-leak sensor error or leak-sensor alarm
Outdoor unit19 guides
- CH40CT sensor error; thermistor is disconnected or shorted; Current-transformer thermistor disconnected or shorted
- CH41Inverter discharge pipe sensor is disconnected or shorted; Inverter compressor discharge pipe thermistor disconnected or shorted
- CH42master outdoor unit: Low-pressure sensor error; slave 1 outdoor unit: Low-pressure sensor error
- CH43master outdoor unit: High-pressure sensor error; slave 1 outdoor unit: High-pressure sensor error
- CH44Outdoor air sensor is disconnected or shorted; Outdoor unit inlet air thermistor disconnected or shorted
- CH45Middle thermistor of outdoor unit condenser coil is disconnected or shorted; Outdoor unit condenser coil middle thermistor disconnected or shorted
- CH46Outdoor unit suction line thermistor is disconnected or shorted; Outdoor unit suction line thermistor disconnected or shorted
- CH47master outdoor unit: Compressor 2 discharge-temperature sensor error; slave 1 outdoor unit: Compressor 2 discharge-temperature sensor error
- CH49master outdoor unit: Outdoor-unit IPM temperature sensor error; slave 1 outdoor unit: Outdoor-unit IPM temperature sensor error
- CH65Heat sink thermistor has disconnected or shorted out; Heat-sink thermistor disconnected or shorted
- CH71master outdoor unit: Outdoor inverter current-transducer sensor error; slave 1 outdoor unit: Outdoor inverter current-transducer sensor error
- CH75master outdoor unit: Outdoor fan current-transducer sensor error; slave 1 outdoor unit: Outdoor fan current-transducer sensor error
- CH113master outdoor unit: Outdoor liquid-pipe temperature sensor error; slave 1 outdoor unit: Outdoor liquid-pipe temperature sensor error
- CH114master outdoor unit: Outdoor subcooling-inlet temperature sensor error; slave 1 outdoor unit: Outdoor subcooling-inlet temperature sensor error
- CH115master outdoor unit: Outdoor subcooling-outlet temperature sensor error; slave 1 outdoor unit: Outdoor subcooling-outlet temperature sensor error
- CH116master outdoor unit: Outdoor-unit low-oil or oil-level sensor error; slave 1 outdoor unit: Outdoor-unit low-oil or oil-level sensor error
- CH153master outdoor unit: Upper heat-exchanger temperature sensor error; slave 1 outdoor unit: Upper heat-exchanger temperature sensor error
- CH154master outdoor unit: Lower heat-exchanger temperature sensor error; slave 1 outdoor unit: Lower heat-exchanger temperature sensor error
- CH194master outdoor unit: Outdoor fan-heatsink temperature sensor error; slave 1 outdoor unit: Outdoor fan-heatsink temperature sensor error
Whole-system faults3 guides
Codes that depend on the exact model5 guides
- 12Indoor unit middle pipe sensor error
- CH12Indoor unit middle pipe thermistor disconnected or shorted
- CH31Current-to-current transformer thermistor is too low
- CH48Outdoor unit coil outlet liquid-line thermistor is disconnected or shorted; Outdoor unit coil outlet liquid-line thermistor disconnected or shorted
- CH63Condenser coil pipe thermistor temperature is too low
Codes can mean different things across model and system families. Every code is in the full lookup for this brand. Last reviewed 2026-08-21.
Is LG thermistor repair worth it?
Parts and timing
The correct LG sensor is model- and location-specific. Indoor and outdoor thermistors are not assumed interchangeable; we confirm the model, sensor position, part number and distributor lead time before you approve work.Our recommendation
Thermistor repair is usually a contained job when the sensor circuit is confirmed, the correct model-specific part is available and the rest of the system is healthy. LG systems commonly have a service life of 8–12 years. For a system over 10 years, major component failures favour replacement. Parts for older ArtCool models may be hard to source, and efficiency loss adds to the running cost of keeping the unit.
If replacement makes more sense, we compare the repair quote with a suitable new system. See our aircon system replacement process.
Other LG repair checks
If testing rules out this part, these are the next checks on the same system.
Workmanship warranty
We stand behind the repair we carry out, and we are straight about the part of the cover we do not set ourselves.
Labour
30-day workmanship warranty. If the same fault returns from our repair, we come back and the labour is on us, with no second diagnostic visit fee.
Parts
Parts carry the distributor's warranty for that component, so the term varies by part. We tell you both terms before you approve the work.
Frequently asked questions about LG thermistor repair in Singapore
What are the signs of a LG thermistor problem?
How do you confirm a LG thermistor fault?
Is a LG error code enough to order the thermistor?
Should I repair or replace my LG aircon?
We cover all of Singapore. Find aircon services in your area.
Describe your situation
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.
