Low
d.71 on Vaillant ecoFIT Pure 825

Your boiler is simply indicating that the heating temperature dial is currently set to its absolute maximum level.

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

Maximum setting of heater control knob

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
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

Locate the radiator temperature dial on the front of your boiler control panelTurn the dial slightly counter-clockwise to reduce the setting below the maximum positionObserve the display to see if the status code clears

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