BoilerFaultCodesYour boiler’s cooling fan is staying on for too long or failing to turn off after the heating cycle, which is preventing the boiler from restarting 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 Overrun
What causes this fault?
This fault occurs when the boiler's internal computer detects that the cooling fan is still spinning long after the burner has switched off. It is physically caused by a sticking electronic relay on the main control board or a faulty sensor that incorrectly tells the boiler the fan is still active. Because the system thinks the fan hasn't stopped, it refuses to start a new ignition cycle as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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