Alarm Z1 Communication fault to compressor control system — No communication or data errors

What does 5331 mean?

This alarm indicates that communication with the compressor control system is missing, or more than 30% of data sent to the inverter returns with errors. This can be caused by power issues, incorrect settings, or cable interference.

• Supply voltage missing in the outdoor unit.
• Incorrect program selection (P-selector) on the I/O-module.
• Interference on the MODbus cable or improper routing of the CANbus cable.
• Defective I/O module or inverter.

Click steps to track your progress.

1. 1

   Check the 230V/400V connections in both the indoor and outdoor units for secure connections.

2. 2

   Verify the P-selector setting on the I/O module matches your Heat Pump model (P=4 for 13 kW 3N~, P=6 for 13 kW 1N~).

3. 3

   If the alarm persists, contact a qualified technician to check MODbus and CANbus cabling for connections and proper routing, ensuring cables are separated from supply voltage by at least 100 mm.