High Lockout
4.7 on Ideal Logic Max Combi

Your boiler has stopped working because the internal fan, which safely clears exhaust fumes, is not running correctly.

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

Fan Fault

What causes this fault?

This fault occurs when the boiler's control board sends a signal to the fan but does not receive the correct speed feedback in return. The most common cause is a mechanical failure within the fan motor or a buildup of dust and debris that prevents the blades from spinning at the required safety speed.

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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Related fault codes

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