Low
A.20 on Viessmann Vitodens 200-W B2KF Combi

Your boiler is simply reminding you that the service interval setting could not be automatically enabled, but it will continue to provide heating and hot water as normal.

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

Service interval could not be activated

From this model's manual
Verified against the Viessmann Vitodens 200 W B2kf Combi 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.

DIY fix possible

Navigate to the main menu and enter the 'Service' section.Try to reset the service interval manually if the prompt appears.Acknowledge the notification by pressing OK to clear the message from the display.

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