Low
24:1 on Viessmann Vitodens 333

Your boiler is simply reminding you that it is time for its regular annual service to ensure it continues to run safely and efficiently.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

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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