High Lockout
F1 on Glow-worm Xtrafast 120

Your boiler has stopped working because it cannot light a flame, which is usually caused by a temporary interruption in the gas supply or a component failure.

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

Ignition fault or no gas supply

What causes this fault?

This fault occurs when the boiler attempts to start but fails to detect a flame after several attempts. The most common reason is a temporary interruption in the gas supply or a build-up of carbon and wear on the components that generate the ignition spark.

This fault is slightly more common during the first cold snap of autumn when internal components that have been idle all summer are suddenly forced to work under high demand.

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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