BoilerFaultCodesYour boiler's internal fan is spinning faster than it should, which has caused 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 speed too high
What causes this fault?
This fault occurs when the boiler's control system loses the ability to regulate the fan, causing it to spin at an unsafe speed. The most common reason is an electrical failure within the fan's internal motor or a malfunctioning circuit board that is sending incorrect voltage to the component.
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 C6 — no call-out fees, no surprises.
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