BoilerFaultCodesYour boiler has lost its connection to the gas valve, meaning it cannot ignite safely and has stopped providing 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.
What causes this fault?
This fault occurs when the boiler's central brain loses communication with the gas valve, which is the component responsible for letting fuel into the burner. The most common reason is a loose or damaged connection cable, but it can also be triggered by a electronic failure within the gas valve itself or the main circuit board. Without this vital connection, the boiler cannot safely ignite and will shut down immediately to prevent any risks.
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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