BoilerFaultCodesYour boiler has stopped working because the internal computer can no longer talk to or control the fan that helps clear exhaust gases.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control unit fault. No communication with the fan.
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic connection with the fan motor, meaning the system can no longer safely clear exhaust gases. The most common reason is a hardware failure within the fan's internal circuitry or a loose connection in the wiring harness that links the components together.
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 E09 — no call-out fees, no surprises.
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