Outdoor Unit Heat Exchanger Sensor (ThOR) Defective / Poor Connection

What does E37 mean?

The outdoor unit heat exchanger sensor (ThOR) is defective (open circuit resistance) or has a poor connection on the outdoor unit PCB. This error may also specify which particular thermistor (Tho-R1 to Tho-R6) has failed, leading to inaccurate temperature readings.

• Outdoor unit heat exchanger temperature sensor (ThOR, e.g., P17) is defective.
• Poor electrical connection to the ThOR sensor.
• Sensor reading is out of range or unstable.
• Wiring harness to the sensor is damaged.
• Environmental factors affecting sensor accuracy.

Click steps to track your progress.

1. 1

   Measure the resistance of the outdoor unit heat exchanger sensor (ThOR) and compare to the specified temperature-resistance chart.

2. 2

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

3. 3

   If a specific sub-code (E37-1 to E37-6) is indicated, identify and test the corresponding thermistor (Tho-R1 to Tho-R6) directly.