BoilerFaultCodesYour boiler has detected a potential internal gas leak during its safety checks and has shut down to keep your home safe.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Gas valve EV2 leak test failed – gas valve leak
What causes this fault?
This fault occurs when the boiler's internal safety checks detect that gas is passing through the system when it should be shut off. The most common reason is a mechanical failure in the gas valve which prevents it from sealing properly, or a communication error from the main control board that incorrectly monitors the gas flow.
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 FA364 — no call-out fees, no surprises.
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