BoilerFaultCodesYour boiler's fan is attempting to spin, but the electronic control board isn't receiving the correct signal back to confirm it is working properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan return flow
What causes this fault?
This fault occurs when the boiler's central computer tries to start the fan but doesn't receive the required electronic pulse to confirm it is spinning at the right speed. It is usually caused by a physical blockage inside the fan's motor, a loose connection in the internal wiring, or a failure in the electronic components that monitor the fan's movement.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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