BoilerFaultCodesYour boiler is failing to start because the internal fan is not spinning at the speed required to clear waste gases.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Start fan speed
What causes this fault?
This fault occurs when the boiler's control system attempts to start the fan but detects that it isn't reaching the necessary speed to safely vent exhaust gases. The most common reason is a mechanical failure within the fan motor or a communication error where the main circuit board cannot correctly read the fan's rotation speed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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