BoilerFaultCodesYour boiler's internal cooling fan is staying on longer than expected after the heating has switched off.
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 status occurs when the internal fan continues to run for an extended period after the boiler has stopped firing to dissipate excess heat from the heat exchanger. It is often caused by heat lingering in the system due to poor water circulation or a pump that isn't moving hot water away fast enough. In some cases, it can also be a sign that the main control board is misreading the temperature sensors.
This is more common during winter months when the boiler is running at higher temperatures for longer periods, leading to more residual heat that needs to be cleared.
DIY fix possible
Check if any radiators have been turned off and reopen them to improve water flowEnsure the external heating controls or room thermostat are set to a lower temperature brieflyReset the boiler using the power button to see if the status clears
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