Low
d.23 on Vaillant ecoFIT Pure 418

This is a normal status indicator showing that your boiler is currently receiving a signal to provide 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

Status of the heating demand (off=Heating off, on=Heating on)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
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 to your desired temperatureEnsure your heating programmer or timer is set to 'On'No action is required if your radiators are warming up as expected

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d.00View →S.04View →

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