Technical description
Fan or fan wiring error
What causes this fault?
This fault occurs when the boiler's control board detects that the fan is either not spinning at the correct speed or has lost electrical communication entirely. The most common reason is an electrical failure within the fan motor itself, though it can also be caused by loose wiring or a communication error from the main circuit board.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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