BoilerFaultCodesYour boiler has stopped working because the internal fan, which safely removes waste gases, is not spinning fast enough.
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 low – the fan lead and connector need checking and may need replacing.
What causes this fault?
This fault occurs when the boiler's control board detects that the fan is not spinning at the required speed to safely expel exhaust fumes. The most common reasons are a build-up of dust and debris within the fan motor bearings or an electrical failure in the wiring that connects the fan to the main power supply.
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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