BoilerFaultCodesWhat the manual says
Manufacturer manualpump / fan overrun
From this model's manual
Verified against the Glow Worm Flexicom Cx installation & service manual, page 45.
What causes this fault?
This occurs when the boiler's internal sensors detect that the heat exchanger is still very hot after the burner has turned off. The boiler keeps the pump or fan running for a short period to move this residual heat away from the internal components and prevent overheating. It is a normal safety function rather than a breakdown.
DIY fix possible
Wait for the process to finish, as this is a normal operating function.Ensure your radiator valves are open to allow heat to dissipate.If the code never disappears, try resetting the boiler once.
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