Low
F.299 on Viessmann Vitodens 200-W B2KF Combi

Your boiler's internal clock has lost its settings or is failing to keep time correctly, which may affect your heating schedules.

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 fault

From this model's manual
Verified against the Viessmann Vitodens 200 W B2kf Combi installation & service manual, page 92.
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's control panelSelect 'Settings' and then 'Time and Date'Manually correct the time and date and press OK to save

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Related fault codes

F.298View →F.300View →

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