Low
d.05 on Vaillant ecoFIT Pure 418

Your boiler is simply displaying the target temperature it is currently trying to reach for your radiators; this is an information status code rather than a fault.

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

Determined heating flow set target temperature

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

No action is required as this is a normal operational status message.If you wish to change the temperature, use the dial or buttons on the boiler fascia.Ensure your external thermostat or programmer is calling for heat if you want the boiler to fire up.

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