Low
d.18 on Vaillant ecoFIT Pure 425

Your boiler is not currently experiencing a fault; it is simply showing a status message to indicate the internal pump is cooling the system down after use.

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 required as this is a normal operating status and not a breakdown.

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Related fault codes

d.00View →d.01View →d.02View →

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