Low
d.08 on Vaillant ecoFIT Pure 418

This is a status code rather than a fault, showing whether your external room thermostat is currently telling the boiler to turn the heating on or off.

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 (0=Room thermostat open, 1=Room thermostat closed)

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 to see if it is set to a temperature higher than the room's current temperatureReplace the batteries in your wireless room thermostatEnsure the heating programmer or timer is set to 'On'

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