Low
F.425 on Viessmann Vitodens 222-F B2TF

Your boiler is having trouble connecting to the internet or its external time source, which may affect your heating schedule and efficiency.

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

Time synchronisation failed

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 101.
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

Check your home internet connection and Wi-Fi router to ensure they are working.Restart your internet router and wait 5 minutes.Reset the boiler using the control panel to prompt a new connection attempt.

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