High Lockout
f029 on Intergas Xtreme 24

Your boiler is unable to control the gas flow correctly, meaning it cannot ignite to provide heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Gas valve fault.

What causes this fault?

This fault occurs when the boiler's control board sends a signal to open the gas valve, but the valve fails to respond or fails to stay open. The most common reason is an internal mechanical failure within the gas valve itself, though it can also be caused by a faulty ignition lead or a communication error from the main circuit board.

Engineer required

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

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