Low
d.23 on Vaillant Turbomax Plus VUW 242EH

This code is simply an information status indicating whether your boiler is set to provide heating and hot water or just hot water only.

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.

What the manual says

Manufacturer manual

Summer/winter function (control knob) 1 = winter; 0 = summer

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 39.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the winter/summer control knob on your boiler's front panelRotate the knob to the '1' position to enable both heating and hot waterRotate the knob to the '0' position to enable hot water only

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