Compressor Discharge Temperature Sensor (ThOD) Defective / Poor Connection

What does E39 mean?

The compressor discharge temperature sensor (ThOD) is defective (open circuit resistance) or has a poor connection on the outdoor unit PCB. This can lead to incorrect discharge temperature monitoring, potentially causing compressor damage.

• Compressor discharge temperature sensor (ThOD, e.g., P18) is defective.
• Poor electrical connection to the ThOD sensor.
• Sensor value is abnormal or unstable.
• Damaged wiring connecting the sensor.
• Overheating condition detected by the sensor.

Click steps to track your progress.

1. 1

   Measure the resistance of the compressor discharge temperature sensor (ThOD) and compare to the specified temperature-resistance chart.

2. 2

   Inspect the ThOD sensor connector on the outdoor unit PCB for secure and clean connection, ensuring no signs of corrosion.