Error E37-3 / Outdoor Red LED Flashes 3 times — Outdoor heat exchanger thermistor Tho-R3 failure

What does E37-3 / Outdoor Red LED 3 flashes mean?

Error E37-3, identified by three flashes of the outdoor unit's red LED, indicates a failure of the outdoor heat exchanger thermistor Tho-R3. This sensor is crucial for temperature readings.

• Outdoor heat exch thermistor (Tho-R3) failure

Click steps to track your progress.

1. 1

   Turn off the main power to the outdoor unit.

2. 2

   Locate the Tho-R3 thermistor and inspect its connection to the outdoor PCB.

3. 3

   Ensure the connector is secure and free of damage.

4. 4

   This typically requires the replacement of the specific thermistor.

5. 5

   Contact a professional technician to diagnose and replace the Tho-R3 thermistor.