BoilerFaultCodesYour boiler has identified that the internal fan is incompatible or incorrectly configured, causing the system to shut down for safety.
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 Fitted
What causes this fault?
This fault occurs when the boiler's control chip fails to recognize the specific fan installed in the unit. The most common reason is a communication error between the fan and the main circuit board, often caused by the wrong part being installed during a repair or a software mismatch on the board itself.
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 L45 — 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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