Low
d.18 on Vaillant ecoFIT Pure 412

Your boiler is currently running its automatic cooling sequence to safely distribute residual heat, confirming it is working exactly as it should.

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)

Engineer required

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

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