BoilerFaultCodesWhat the manual says
Manufacturer manualpump / fan overrun
From this model's manual
Verified against the Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
What causes this fault?
This status occurs when the boiler has just finished heating your home or water and needs to dissipate excess heat from the internal heat exchanger. The internal pump and fan continue to run for a few minutes to circulate water and air, preventing the components from overheating or being damaged by 'heat soak'. This is a built-in safety feature rather than a mechanical failure.
DIY fix possible
Wait for 5 to 10 minutes for the boiler to complete its cooling cycleCheck that your radiator valves are open to allow heat to dissipateIf the code persists for hours, try resetting the boiler
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