Viessmann · Vitodens 100-W Boiler
The burner is in a fault state because an internal error counter has exceeded its limit. This usually means multiple minor faults have occurred, indicating an underlying problem.
Click steps to track your progress.
Reset the boiler by briefly turning off and on its power supply.
Check the fault history (message history) on the programming unit for other active or recently remedied faults.
If the fault recurs, contact a qualified heating engineer to perform a thorough fault analysis.