Technical description
Fan speed failure
What causes this fault?
This fault occurs when the boiler's control system detects that the internal fan is not rotating at the speed required to safely extract combustion fumes. The most common reason is a mechanical failure within the fan motor or a communication error where the main circuit board can no longer control the fan properly.
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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