Low
d.23 on Vaillant ecoFIT Pure 425

This is a normal status message showing whether your central heating is currently requested to be on or off; it is not a system fault.

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 or programmer if the heating is not coming on when expectedEnsure the boiler's heating control knob is turned to the 'on' positionNo action is required if the heating is working as intended

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Related fault codes

d.00View →d.01View →

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