BoilerFaultCodesYour boiler has stopped working because it detects that the internal fan is the incorrect model for this specific unit.
Book a Gas Safe engineer within 24–48 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like J45 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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