Emergency Lockout
FA on Worcester Bosch Greenstar CDi Compact

Your boiler thinks it still sees a flame even though it has commanded the gas to turn off, which is a safety conflict.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

False flame error (Flame detected after burner stop) or Gas valve EV2 leak test failed

What causes this fault?

This fault occurs when the boiler's internal sensors continue to detect a flame even after the system has commanded the gas valve to close. This is usually caused by a gas valve that is physically stuck open and leaking fuel, or a faulty control board that is misinterpreting electrical signals from the flame sensor.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F0View →E5View →

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