E1 n 22 (FJM Indoor) — Heat exchanger in temperature sensor error

What does E1 n 22 mean?

The FJM indoor unit displays E1 n 22, indicating an open or short circuit in the heat exchanger 'in' temperature sensor. This sensor monitors the refrigerant temperature entering the indoor coil.

• Faulty heat exchanger 'in' sensor
• Loose or damaged sensor wiring
• Issue with the indoor unit's PCB

Click steps to track your progress.

1. 1

   Turn off the power to the FJM indoor unit at the circuit breaker.

2. 2

   Visually inspect the heat exchanger 'in' sensor (typically located near the refrigerant pipes on the indoor coil) for damage.

3. 3

   Check the sensor's wiring connection to the indoor unit's PCB for security.

4. 4

   Restore power. If the error persists, contact a qualified technician to test or replace the sensor or PCB.