Error Code 12 — Outdoor ambient temperature sensor fault

What does 12 mean?

There is an electrical failure with the sensor that measures the outdoor air temperature. This sensor is connected to the PCB.

• Defective ambient temperature sensor
• Loose or damaged sensor wiring
• Open or shorted sensor circuit

Click steps to track your progress.

1. 1

   Check that the sensor wiring is firmly and correctly connected to Plug CN-14 on the PCB.

2. 2

   Inspect the sensor wiring for any damage.

3. 3

   Test the sensor's resistance against the values in the manual's reference section.

4. 4

   Replace the sensor if it is found to be faulty.