Low
S.00 on Vaillant ecoTEC exclusive

Your boiler is currently in standby mode because it has not received an instruction from your thermostat to provide 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 Exclusive installation & service manual, page 53.
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 is set to a temperature higher than the current room temperatureEnsure your programmer or digital timer is set to 'On' for the time periodCheck that boiler mode is set to both heating and hot water if required

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