High Lockout
F03 on Ideal Logic Max Combi

Your boiler has stopped working because the fan that removes waste gases is not spinning correctly, causing the system to shut down for safety.

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 system detects that the fan is not spinning or is rotating at the wrong speed to safely clear waste gases. The most common reason is a mechanical failure within the fan motor or a communication error between the fan and the main circuit board. Without the fan functioning correctly, the boiler cannot safely ignite and will shut down as a precaution.

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

F1View →L2View →

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