Low
d.71 on Vaillant ecoMAX 618

Your boiler is limiting the maximum temperature it allows for the water circulating through your radiators to prevent the system from getting too hot.

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

Max. target value for heating-system flow temperature

DIY fix possible

Check your thermostat settings to see if the target temperature is set too lowAdjust the heating flow temperature dial/setting on the front of the boiler control panelPress the i button to clear the status code and return to the main display

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