Low
d.13 on Vaillant ecoFIT Pure 435

Your boiler is providing an update on whether the pump responsible for moving hot water around your system is currently running or stopped.

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

This fault may be fixable without an engineer. Check your manual first.

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