Technical description
No fan signal available
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic connection with the fan motor, which is responsible for pulling fresh air in and pushing exhaust gases out. The most common reason is a mechanical failure within the fan itself or a loose connection in the internal wiring that prevents the computer from confirming the fan is spinning safely.
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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