Viessmann 24 Fault Code
The Viessmann 24 fault code means: your boiler has detected a critical internal error in its main computer that prevents it from turning on the burner safely.. It appears on 1 Viessmann model in our database.
Technical description: Burner control unit fault
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Viessmann models that show the 24 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Viessmann 24 fault code information on this page is sourced and cross-checked against the official Viessmann service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026