Low
F.299 on Viessmann Vitodens 200-W B2HF System

Your boiler has lost its internal time and date settings, which may disrupt 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 B2hf System 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

Locate the control panel on the front of the boilerNavigate to the 'Settings' menu using the touchscreenSelect 'Time and Date' and manually update them to the current valuesConfirm the changes and check if the fault code clears

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F.298View →F.345View →

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