Low
d.18 on Vaillant ecoFIT Pure 835

Your boiler is simply showing its current internal setting for how the water pump behaves after heating, rather than reporting a broken part.

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

Pump overrun operating mode (1=Comfort, 3=Eco)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
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

This is an information code, not a fault; no action is required.If you wish to change the energy saving mode, access the installer menu to toggle between Comfort and Eco.Press the 'Back' or 'Menu' button to return to the main temperature display.

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