Technical description
fan overrun
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is still spinning even though the heating or hot water demand has finished. The most common reason is a communication error between the fan and the main circuit board, or a sticking internal component that fails to cut power to the fan motor. For safety, the boiler will pause operation until it detects the fan has correctly stopped.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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