High Lockout
Red flashing light on Glow-worm Compact

Your boiler has stopped working to protect itself and simply needs to be restarted to clear a temporary error.

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

Fault occurs; requires reset (Turn On/Off switch to 0, wait five seconds, then to I).

What causes this fault?

This fault happens when the boiler tries to light the flame but fails to detect one after several attempts. It is usually caused by a temporary interruption in the gas supply or a worn-out component that struggles to create the initial spark. To keep you safe, the system shuts down completely until it is manually told that it is okay to try again.

This issue is more frequent during the first cold snap of winter when older components are under sudden strain after being idle over the summer.

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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