Low
d.13 on Vaillant ecoFIT Pure 425

Your boiler is displaying the current operating status of your external hot water pump rather than an actual error message.

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 hot water circuit's circulation pump

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 if your external hot water timer or thermostat is calling for heatPress the 'i' or 'back' button to return the screen to the main temperature displayObserve if the code changes when you turn your hot water on or off

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