Low
F.473 on Viessmann Vitodens 200-W B2KF Combi

Your boiler is currently idle because it has not received a signal from your thermostat or hot water tap to start producing heat.

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 heat demand

From this model's manual
Verified against the Viessmann Vitodens 200 W B2kf Combi 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 room thermostat is set higher than the current room temperature.Ensure your heating timer or smart controller is set to 'On'.Open a hot water tap to see if the boiler fires up for hot water demand.

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