Low
F.473 on Viessmann Vitodens 200-W B2HF System

Your boiler is currently idle because it is not receiving a signal from your thermostat or heating controls 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 B2hf System 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 that your room thermostat or smart controller is set to a temperature higher than the current room temperature.Ensure your heating programmer or timer is set to 'On' or in a timed period.Check if your thermostat batteries need replacing or if your internet-connected controller has lost its Wi-Fi connection.

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Related fault codes

F.474View →F.475View →

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