High Lockout
F1 on Glow-worm Flexicom cx

Your boiler has stopped working because it cannot light the gas required to provide heat or hot water.

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

The burner fails to ignite

What causes this fault?

This fault occurs when the boiler's control system attempts to light the burner but fails to detect a flame after several attempts. The most common reasons include a lack of gas reaching the unit, a worn-out ignition spark electrode, or a blockage within the burner system preventing the gas from catching light.

This fault is more common during extreme cold snaps, as external gas meters or pipes can sometimes freeze or experience pressure drops that prevent a consistent gas flow.

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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