Alarm 234 - Exchange sensors flow / return

What does 234 mean?

The Heat Pump detects that the return line temperature is hotter than the flow line. This suggests that the temperature sensors for flow and return have been switched during installation or a major flow issue.

• Connection of supply and return lines are switched around.
• Flow and return sensors are incorrectly installed or wired.

Click steps to track your progress.

1. 1

   Verify that the flow and return pipes are correctly connected to the Heat Pump according to the installation manual.

2. 2

   Check the wiring and placement of the flow and return temperature sensors (BT10 and BT11) to ensure they are not swapped.

3. 3

   If you suspect the sensors are switched, contact your installer or a NIBE service technician to correct the wiring.