Low
S.31 on Vaillant Home Combi

Your boiler is currently in summer mode and is not providing heating because your controls have not requested it.

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

Noheatingdemand:Summermode,eBUScontroller,waitingperiod

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 34.
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

Check your room thermostat or smart controller settingsIncrease the desired room temperature setting on your controllerEnsure the heating timer is currently set to an 'ON' period

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Related fault codes

S.30View →S.34View →

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