Low
A.20 on Viessmann Vitodens 200-W B2HF System

Your boiler is simply notifying you that it was unable to set a reminder for its next scheduled service.

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 B2hf System 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 on the control panelGo to 'Settings' and then 'Service'Attempt to manually reset the service interval or acknowledge the notification

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