Low
F.11 on Viessmann Vitodens 200-W B2KF Combi

Your boiler's sensor is having trouble communicating with the external solar panel system, meaning your home is currently not using solar energy to assist with your hot water or heating.

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

No solar DHW heating or central heating backup

From this model's manual
Verified against the Viessmann Vitodens 200 W B2kf Combi installation & service manual, page 87.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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