Low
S.0 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently in standby mode because it is not receiving a request for heat from your thermostat or hot water timer.

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 (heating operation)

DIY fix possible

Check your room thermostat is set to a temperature higher than the current room temperature.Ensure your heating programmer or central heating timer is set to 'On'.Check if your hot water cylinder thermostat is calling for heat if you have a traditional tank system.

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Related fault codes

S.1View →S.2View →S.3View →

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