Low
d.09 on Vaillant ecoFIT Pure 418

Your boiler is simply displaying the target temperature being requested by your external room thermostat, which is a normal status message rather than an actual 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

Heating flow set target temperature that is set on the eBUS room thermostat

DIY fix possible

Check your room thermostat to see what temperature it is set toAdjust the thermostat settings if the house is too hot or too coldNo action is required if your heating is working as expected

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Related fault codes

d.00View →d.40View →

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