BoilerFaultCodesYour boiler has lost communication with its gas control unit, meaning it cannot safely ignite to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas valve connection cable fault
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic link with the gas valve, which is the component responsible for releasing fuel into the burner. The most common reason is a loose or damaged connection pin within the wiring harness, or an internal electronic failure within the gas valve itself that prevents it from responding to commands. Because the boiler can no longer safely regulate the flow of gas, it shuts down immediately as a safety precaution.
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 E09 — 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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