Low
d.18 on Vaillant ecoFIT pure

Your boiler is currently running its internal pump to cool down or circulate heat, which is a normal setting rather than a malfunction.

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.

Technical description

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

DIY fix possible

No action is usually required as this is an advisory status code.If you wish to change how long the pump runs, access the installer menu under d.18.Switch between setting 1 (Comfort) for frequent circulation or 3 (Eco) for less frequent circulation.

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Related fault codes

d.01View →d.02View →

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