Low
d.23 on Vaillant ecoTEC plus System

Your boiler is currently operating normally and is simply indicating that no heating is required at this moment.

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 (Summer mode), on=Heating on

DIY fix possible

Check your thermostat settings to ensure the heating is set to 'on'Increase the target temperature on your room thermostatEnsure your heating programmer is currently within an active time schedule

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Related fault codes

d.22View →d.24View →

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