High Lockout
Fan Fault on Ideal Logic Max System

Your boiler has detected a problem with the fan that clears exhaust gases, preventing the system from starting up for safety reasons.

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

Wiring from Fan to PCB insecure or lacks continuity, or failure of 230 VAC supply at Fan connections.

What causes this fault?

This fault occurs when the boiler's computer cannot detect that the fan is spinning fast enough to safely clear exhaust fumes from the building. The most common cause is a mechanical failure of the fan motor itself, though loose electrical connections or a fault with the main control board can also stop the fan from receiving power.

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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