BoilerFaultCodes.com
L2 High Lockout

Your boiler has stopped working because it cannot light a flame, which is often caused by a lack of gas supply or a blocked pipe.

Call an engineer soon

Book a Gas Safe engineer within 24–48 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 tries to light itself several times but fails to detect a flame, causing the system to shut down for safety. The most common reasons are a lack of gas reaching the unit, a blocked pipe that carries away waste water, or a dirty internal component that can no longer create a spark. It can also happen after a temporary disruption to your local gas supply or if the meter has run out of credit.

This fault is much more common during freezing winter temperatures, as the external condensate pipe can freeze solid and prevent the boiler from lighting.

Typical repair cost £100-350 (including labour)

DIY fix possible

Check if your gas meter has credit and that the gas emergency control valve is open.If it is freezing outside, check if your white condensate pipe is frozen and thaw it with warm water.Press the 'Restart' button on the boiler display to try again.

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