Emergency Lockout
16 on Glow-worm Xtramax HE

Your boiler has detected that gas is continuing to flow when it should have stopped, which is a significant safety concern.

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

GAS LEAK THROUGH THE SAFETY ELECTRIC VALVES: CHECK THE SAFETY ELECTRIC VALVE

What causes this fault?

This fault occurs when the boiler's internal sensors detect that gas is still passing into the burner even after the system has commanded the flow to stop. The most common reason is that the seals inside the gas valve have become stuck or damaged, preventing it from closing fully, though a communication error from the main control board can also trigger this warning.

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

F1View →F15View →F17View →

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