Your boiler's fan is continuing to run for longer than expected after the heating or hot water has finished.
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 over run
What causes this fault?
This status occurs when the boiler's fan continues to spin after the demand for heating or hot water has ended to clear any remaining combustion gases from the system. While it is usually part of the boiler's normal cooling-down process, it can indicate a minor delay in the communication between the control board and the fan. In rare cases, it may signal that the fan is beginning to wear out or that there is a slight fault with the electrical signals from the main circuit board.
DIY fix possible
Wait up to 20 minutes to see if the fan stops automaticallySwitch the boiler off and back on at the fused spur switchCheck if the boiler is stuck in a 'Comfort' pre-heat mode
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