Low
21:0 on Viessmann Vitodens 222-F

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.

What the manual says

Manufacturer manual

No maintenance indication for the burner

From this model's manual
Verified against the Viessmann Vitodens 222 F installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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