BoilerFaultCodesWhat the manual says
Manufacturer manualpump overrun
From this model's manual
Verified against the Glow Worm Ultracom 2 Sxi installation & service manual, page 55.
What causes this fault?
This status occurs because the boiler needs to dissipate residual heat from the internal heat exchanger after the burner has turned off. It is a normal safety function where the pump continues to run to move hot water away from the unit and into the system. This prevents the internal components from overheating or becoming damaged by stagnant, high-temperature water.
DIY fix possible
Check if the display changes to a normal heating mode or standby after a few minutesEnsure your radiator valves are open to allow water to circulateMonitor the boiler to see if the status clears itself once the temperature drops
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