Low
23:1 to 23:24 on Viessmann Vitodens 333

Your boiler is simply reminding you that the annual service interval you set has now been reached.

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

Time interval adjustable from 1 to 24 months for burner maintenance

Engineer required

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

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