Low
21:0 on Viessmann Vitodens 100-W / 200-W

Your boiler is simply notifying you that a routine service is due based on its operating hours.

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

No maintenance indication for the burner

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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