Pipe Sensor Abnormal

What does P2 mean?

The indoor coil pipe sensor is abnormal, indicating an open circuit, short circuit, or incorrect resistance. This prevents accurate refrigerant temperature monitoring, which is critical for defrost logic and coil protection.

• Pipe sensor (21) is abnormal.
• Faulty temperature/pressure sensor on a pipe.
• Wiring issue to the pipe sensor.

Click steps to track your progress.

1. 1

   Measure the resistance of the pipe sensor at its leads — compare to a resistance-temperature chart if available.

2. 2

   Inspect the sensor's wiring and connector on the indoor unit PCB for damage, corrosion, or secure seating.

3. 3

   Verify the sensor is securely attached to the refrigerant pipe for proper thermal contact.