Low
F.299 on Viessmann Vitodens 222-F B2TF

Your boiler's internal clock has lost its settings, which can happen after a power cut or a long period of being switched off.

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

Real time clock setting incorrect

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 95.
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 boiler control panelSelect 'Settings'Choose 'Time and Date' and update to the current local timeConfirm the settings to clear the fault code

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Related fault codes

F.298View →F.420View →

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