BoilerFaultCodesTechnical 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 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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