BoilerFaultCodesYour boiler has detected that the internal fan is spinning too fast, which prevents the system from starting up safely.
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
What causes this fault?
This fault occurs when the boiler's control board receives a signal that the fan is spinning at an unsafe speed, often due to a communication error between the motor and the electronics. It can be caused by a failing fan motor that can no longer regulate its rotation or a fault on the main circuit board that is misreading the fan's performance. In some cases, a blocked flue or a faulty air pressure switch can also trick the system into reporting this incorrect speed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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