Emergency Lockout
E384 on Baxi Duo-tec Combi

Your boiler thinks it sees a flame even though the gas supply should be turned off, which is a safety conflict that prevents the system from starting.

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

Flame detected when gas valve off

What causes this fault?

This fault occurs when the boiler's internal sensors detect a flame after the heating cycle has ended and the gas should be cut off. The most common reason is a gas valve that is physically stuck open or leaking, though it can also be caused by an electrical 'ghost' signal from a damaged sensor or a faulty control board.

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

E128View →E129View →E130View →

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