Low
d.08 on Vaillant ecoTEC plus aquaPLUS

Your boiler has received a signal from your thermostat or external programmer to start heating your home.

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

External controls heat demand

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual.
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 see if it is turned up higher than the current room temperature.Verify if your central heating timer or programmer is currently set to an 'on' period.No action is required if you actually want the heating to be running, as this is a status message rather than a fault.

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