Low
S.00 on Vaillant ecoTEC Pro 30

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 Pro 30 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 to ensure the target temperature is set higher than the current room temperatureEnsure your heating programmer or timer is currently in an 'ON' periodTurn on a hot water tap to see if the boiler activates in response

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