Low
d.23 on Vaillant Turbomax Plus 828

Your boiler is currently set to summer mode, which means it is configured to only provide hot water and will not turn on your radiators.

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 temperature control knob on the front panel of your boilerTurn the knob to the 'winter' position (usually indicated by a radiator icon)Check if the heating activates once the boiler recognizes the setting change

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