Low
d.09 on Vaillant ecoFIT pure

Your boiler is simply showing the target temperature requested by your room thermostat and is operating as normal.

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 if the temperature has been adjustedNo action is required as this is an information code, not a faultWait for the boiler to reach the requested temperature and the code will disappear

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Related fault codes

d.00View →d.40View →

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