Low
S.00 on Vaillant ecoTEC plus aquaPLUS

Your boiler is working correctly but is currently resting because it hasn't been told to turn on by your thermostat or 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.

What the manual says

Manufacturer manual

No heat demand (heating operation)

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual, page 38.
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 that your room thermostat is turned up higher than the current room temperatureEnsure your programmer or heating timer is set to an 'ON' periodCheck if the batteries in your wireless thermostat need replacing

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