Low
d.08 on Vaillant ecoFIT Pure 825

Your boiler is currently receiving a signal from your room thermostat telling it to switch on, which is a normal part of its operation.

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

Status of the 230V thermostat

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 29.
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 your desired temperatureEnsure your thermostat has fresh batteries if applicableIf the boiler is working normally, ignore this code as it is just a status indicator

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