High Lockout
528 on Ideal Ideal Classic SE15P FF

Your boiler's fan is failing to start or communicate with the control board, meaning the system cannot safely clear exhaust fumes to stay running.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 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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