BoilerFaultCodesYour boiler has detected that the internal fan is spinning faster than it should, which has caused the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan speed too high – check the fan harness and connector
What causes this fault?
This fault occurs when the boiler's control board loses its ability to regulate the fan's rotation, causing it to spin at an unsafe speed. The most common reason is a communication failure between the electronic heart of the boiler and the fan motor, often due to a faulty circuit board or a loose connection. In some cases, the fan motor itself has suffered internal damage and can no longer respond to the commands meant to slow it down.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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