High Lockout
J45 on Ideal HP290

Your boiler has stopped working because it detects that the internal fan is the incorrect model for this specific unit.

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

Wrong Fan Motor Fitted

What causes this fault?

This fault occurs when the boiler's control board detects that the installed fan is not communicating correctly or is incompatible with this specific model's software. It is most commonly caused by a technician installing the wrong replacement part or a communication error between the main circuit board and the fan motor.

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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