Viessmann 24:1 Fault Code
Also written as 241 — same fault.
The Viessmann 24:1 fault code means: your boiler is simply reminding you that it is time for its regular annual service to ensure it continues to run safely and efficiently.. It appears on 1 Viessmann model in our database.
Technical description: 'Maintenance' display (the address is automatically set and must be manually reset after maintenance has been completed)
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 24:1 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Viessmann 24:1 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