BoilerFaultCodesYour boiler's internal cooling fan is staying on longer than expected after a heating cycle to ensure any remaining gases are cleared.
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: Fan overrun
What causes this fault?
This scenario occurs when the boiler's internal computer keeps the fan spinning after the burner has turned off to clear away residual heat and combustion gases. While it is often just a normal part of the cooling process, it can also happen if the system detects that temperatures inside the unit are staying high for longer than they should. In rare cases, it may indicate that the control board is misreading signals from the fan.
DIY fix possible
Wait up to 10 minutes to see if the fan stops automaticallyCheck that the thermostat is not calling for heatReset the boiler using the flame symbol button
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