A Class Heat Pump displaying 'Bus Initialising' on the user interface, what does this mean?

'Bus Initialising' occurs when the indoor wiring centre is unable to find the outdoor unit on the communication network. This can be due to a few different causes and may require an engineer to investigate. Possible causes include:

  • Corruption of the SD card fitted to the wiring centre (water module) - powering off the unit, removing the SD card and powering the system back up may resolve this.
  • Power loss to the outdoor unit - It is worth checking the outdoor rotary isolation switch, and circuit breakers are not in the off positions
  • A loose connection or break in the Modbus communication cabling - This will need testing by an engineer
  • An issue with one of the 4 components connected to the Modbus network (SEC board, Master board, Water module and User interface) - This will require investigation by an engineer.

This is not covered under the manufactures guarantee.

Please find a list of approved Dimplex service agents via the below link..


Note: From software 1.17, this message will appear as 'Network Refreshing'.

Applicable Models:

A6M, A8M, A12M, A16M

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