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.

Technical description

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

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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Related fault codes

d.00View →S.04View →

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