Low
S.00 on Vaillant ecoTEC Plus 826

Your boiler is currently in standby mode because it has not been asked to provide any heating or 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

Heating: No heat demand

From this model's manual
Verified against the Vaillant Ecotec Plus 826 installation & service manual, page 47.
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 settings to ensure the heating is set to 'On' or 'Scheduled'.Increase the target temperature on your room thermostat to be higher than the current room temperature.Ensure your hot water timer or programmer is active if you require hot water.

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