Low
S.31 on Vaillant Combi Compact 242EB

Your boiler is currently set to summer mode, which means it is ignoring the thermostat and will only provide hot water, not heating.

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

No heat demand summer operating mode

DIY fix possible

Locate the radiator temperature dial on the front of the boiler control panel.Turn the dial clockwise to the desired temperature setting to enable central heating.Ensure your wall thermostat is turned up and calling for heat.

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Related fault codes

S.30View →S.34View →

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