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.

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.

Technical description

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

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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