Low
d.23 on Vaillant ecoTEC plus Aquaplus

Your boiler is currently indicating that it is adjusting its internal settings for the seasonal transition between heating and hot water mode.

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

Summer/winter function (control knob)

DIY fix possible

Check the position of the physical central heating control knob on the front panelRotate the knob to your desired temperature setting to ensure it is not stuck between modesObserve the display to see if the code clears once the setting is firmly selected

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