LG AC Error Code CH02 – Causes and Quick Fix Guide

You turn on your LG air conditioner expecting cool air, but instead, you see CH02 flashing on the display.

Frustrating, right?

The good news is that this error is usually fixable. In most cases, it is related to a sensor or communication issue, not a major system failure.

Let’s break it down in simple terms so you can fix it fast.

What Is LG AC Error Code CH02?

LG AC error code CH02 indicates a problem with the indoor temperature sensor (thermistor).

This sensor is responsible for:

• Measuring room temperature

• Sending data to the control board

• Helping the AC maintain the desired cooling level

When the sensor fails or sends incorrect signals, the system displays CH02.

Common Causes of CH02 Error

Here are the most common reasons why this error appears:

1. Faulty Temperature Sensor

The indoor thermistor may be damaged or worn out over time.

2. Loose or Broken Wiring

Connections between the sensor and control board may be:

• Loose

• Corroded

• Disconnected

3. Sensor Short Circuit

If the sensor wiring is shorted, it can send incorrect readings.

4. Control Board Issue

In rare cases, the main PCB (control board) may not be reading the sensor correctly.

5. Moisture or Dirt Build-Up

Dust or moisture inside the unit can interfere with sensor performance.

How to Fix LG AC Error Code CH02

Try these step-by-step fixes before calling a technician:

Step 1: Power Reset the AC

• Turn off the AC

• Unplug it from the power source

• Wait for 5–10 minutes

• Turn it back on

Sometimes, a simple reset clears temporary glitches.

Step 2: Inspect the Sensor Wiring

• Open the indoor unit panel

• Locate the temperature sensor

• Check for:

  • Loose connections

  • Damaged wires

Reconnect any loose wiring carefully.

Step 3: Clean the Indoor Unit

• Remove dust around the sensor area

• Use a soft brush or dry cloth

Avoid water or harsh cleaning agents.

Step 4: Test or Replace the Sensor

If you have basic technical skills:

• Use a multimeter to test the thermistor

• If readings are abnormal, replace the sensor

Sensor replacement is usually affordable and quick.

Step 5: Check the Control Board

If the issue persists:

• The PCB may be faulty

• This requires professional diagnosis

When to Call a Technician

Call a professional if:

• The error keeps coming back

• You notice burnt wires or smell

• The AC stops cooling completely

• You are not comfortable opening the unit

How to Prevent CH02 Error

Prevent future issues with these simple habits:

• Clean filters regularly

• Schedule periodic maintenance

• Avoid moisture exposure

• Ensure stable power supply

Final Thoughts

LG AC error code CH02 might look serious, but it usually points to a temperature sensor issue.

Start with a simple reset, check the wiring, and clean the unit. In many cases, that is all it takes.

Read More:

LG AC error code CH12

LG AC error code CH41

LG AC error code CH61