Low
d.01 on Vaillant ecoFIT Pure 412

Your boiler is simply moving leftover warm water through your radiators to ensure the system cools down safely after a heating cycle.

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 in heating mode

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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