Low
d.23 on Vaillant Turbomax Plus 824/828E

This code is not actually an error; it simply confirms whether your boiler is currently set to provide only hot water or both heating and hot water.

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 domestic hot water/heating selector knob on the front control panel.Turn the knob to the '1' (Winter) position if you want heating and hot water, or '0' (Summer) if you only want hot water.Wait a few moments for the boiler display to reflect your chosen setting.

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