High Lockout
Slow Flashing (2Hz) on Glow-worm Micron 60FF

Your boiler has failed to ignite and has locked itself out for safety, meaning you currently have no heating 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

Slow Flashing (2Hz)

What causes this fault?

This fault occurs when the boiler attempts to start up but fails to detect a flame after several attempts. The most common reasons are a worn-out ignition spark that can no longer light the gas or a faulty gas valve that isn't letting fuel into the burner.

This issue is more frequent during the first cold snap of winter when components that have been idle over summer are suddenly put under heavy strain.

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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