BoilerFaultCodesYour boiler has detected that the internal fan, which safely pushes exhaust fumes outside, is not spinning at the correct speed.
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: Fan speed incorrect
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is failing to reach or maintain the specific speed required to safely clear exhaust gases. The most common reasons are a build-up of debris within the fan motor, a physical blockage in the flue, or an electrical failure where the circuit board can no longer communicate with the fan.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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