BoilerFaultCodesYour boiler has paused its operation because it is not receiving the correct feedback signal from the fan that pushes exhaust gases out of the system.
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 control board sends a command to the fan but does not receive the expected signal back to confirm it is spinning at the right speed. It is often caused by a mechanical failure within the fan motor or a communication breakdown in the electrical wiring between the fan and the main computer. Without this confirmation, the boiler stops for safety to ensure harmful exhaust gases are being correctly removed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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