Low
d.23 on Vaillant aquaPLUS

Your boiler is currently set to summer mode, which means it will provide hot water but your central heating is switched off.

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

Locate the left-hand control knob on the boiler fascia with the radiator icon.Turn the knob clockwise to your desired heating temperature setting.The 'd.23' status should change as the boiler switches back to winter mode.

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Related fault codes

d.22View →d.25View →

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