Warning Z1 Condensate sensor cooling mode TR4 open circuit — Condensate sensor TR4 circuit broken

What does 5420 mean?

This warning indicates that the circuit for sensor TR4 is broken, with a resistance reading greater than 170 kOhm. This could be due to a loose connection, a broken sensor, or a faulty I/O module.

• Screw terminal on I/O module for sensor TR4 is not properly tightened.
• Broken sensor TR4 or its signal cable.
• Defective I/O module.

Click steps to track your progress.

1. 1

   Check the screw terminal for sensor TR4 on the I/O module and ensure it is tightened properly.

2. 2

   If the warning persists, contact a qualified technician to measure the sensor's resistance and inspect the signal cable.

3. 3

   Do not attempt to replace sensors or I/O modules unless you are a qualified installer.