High Lockout
LED 1 (RESET) Constant Light on Glow-worm Micron 60FF

Your boiler has failed to light after several attempts and has locked itself out for safety.

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 Lockout

What causes this fault?

This fault occurs when the boiler fails to detect a flame after several ignition attempts, causing it to shut down as a safety precaution. The most common reasons include a worn-out spark electrode that can no longer light the gas, or a faulty gas valve that isn't letting fuel into the burner. In some cases, the internal control board may be failing to send the correct signals to start the ignition process.

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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