F.342 — No central heating, no DHW heating (Communication error, BCU burner control unit)

What does F.342 mean?

There is no central heating or domestic hot water due to a communication error with the Burner Control Unit (BCU). This indicates an issue with connections or the internal CAN bus.

• Connecting cable to burner control unit faulty (plug X4)
• Faulty plug-in connections or cables of the internal CAN
• Faulty component connected to BCU

Click steps to track your progress.

1. 1

   Reset the appliance.

2. 2

   Contact a qualified technician to check the connecting cable to the burner control unit (plug X4).

3. 3

   A technician may need to check all internal CAN plug-in connections to identify the faulty component.