Low
d.13 on Vaillant ecoFIT Pure 418

Your boiler is displaying the current operating status of the external pump that moves hot water around your system, rather than indicating a breakdown.

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 heating and hot water are still working as normalObserve if the code changes to '0' (off) or '1' (on) when you change thermostat settingsConsult your manual to confirm this is a status indicator rather than a lockout fault

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