BoilerFaultCodesYour boiler has stopped working because it cannot communicate properly with the gas valve that controls the fuel supply.
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 error – wiring could be disconnected or error with gas valve
What causes this fault?
This fault occurs when the boiler’s main control board loses its electrical connection with the gas valve, which is the component that moves fuel into the burner. The most common reason is a loose or damaged wiring plug, though it can also be caused by an internal electronic failure within the gas valve itself.
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 A09 — 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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