BoilerFaultCodesTechnical description
DHWmode:Fanoverrun
What causes this fault?
This occurs when the boiler has finished heating your water and needs to purge excess heat from the internal heat exchanger. The system spins the fan for a short duration to ensure the internal components do not overheat once the burner has switched off. It is a standard safety and maintenance function rather than a mechanical failure.
This status is more noticeable during summer when the boiler is only used for hot water, as the lack of central heating circulation makes the cooling process more distinct.
DIY fix possible
No action required; this is a normal operating status and not a fault.Wait for the fan to stop automatically once the internal components have cooled.If the code never disappears, try restarting the boiler using the power button.