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 EV1 leak test failed
What causes this fault?
This fault occurs when the boiler's internal safety system detects that the gas valve is not sealing correctly and is allowing fuel to seep through even when it should be closed. The most common reason is a mechanical failure within the gas valve itself or a fault in the main control board that incorrectly monitors the valve's position. Because this involves the integrity of the gas supply, the boiler shuts down immediately to prevent an unsafe build-up of gas.
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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