Low
d.23 on Vaillant ecoFIT Pure 835

This is a normal status message showing whether your heating is currently being requested to run by your controls.

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 if your room thermostat or programmer is turned up higher than the current room temperatureEnsure your heating timer is set to an 'on' periodCheck that the boiler is not in summer mode (hot water only)

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