BoilerFaultCodesYour boiler's fan is failing to start or communicate with the control board, meaning the system cannot safely clear exhaust fumes to stay running.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air flow - Fan not running / no tacho signal
What causes this fault?
This fault occurs when the boiler's control board sends power to the fan but does not receive a signal back to confirm it is spinning. The most common reason is a mechanical failure of the fan motor or a loose electrical connection that prevents the system from safely clearing exhaust gases.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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