Alarm Heat Pump Z2 fluid line in cooling mode sensor TR4 faulty

What does 5425 mean?

This alarm indicates a fault with the fluid line sensor TR4 for Heat Pump Z2 while in cooling mode. This could be due to a sensor failure or a short circuit in the cable. It triggers after 3 faults in 2 hours, or 15 minutes of continuous failure or short circuit.

• sensor TR4 or its signal cable failure.
• Screw terminal on the I/O board to sensor TR4 not tightened.
• sensor TR4 or its signal cable short circuited.
• Defective I/O board.

Click steps to track your progress.

1. 1

   Locate the I/O board and check the screw terminal connection for sensor TR4 to ensure it is tightened.

2. 2

   If the alarm persists, contact a qualified technician to check the sensor and its cabling.

3. 3

   Contact customer support if the issue continues.