BoilerFaultCodesYour boiler has detected an issue with the fan that safely clears exhaust gases, 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: Fan fault
What causes this fault?
This fault occurs when the boiler's control board sends a command to the fan but does not receive the correct signals back to confirm it is spinning at the right speed. The most common reasons are a mechanical failure of the fan motor, a loose connection in the internal wiring, or a fault on the main circuit board that manages power to the fan.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F41 — no call-out fees, no surprises.
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