High Lockout
LC on Ideal Logic Max System

Your boiler has attempted to restart itself too many times in a short period because it is detecting a recurring problem.

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

Restart occurs 5 times within 15 minutes.

What causes this fault?

This fault occurs when the boiler detects an underlying issue, such as a failing ignition or a gas supply problem, and attempts to fix itself by restarting. If the boiler has to do this five times in fifteen minutes without success, it will stop running entirely to prevent damage. The root cause is usually a component that is struggling to either create a spark or maintain a steady flame.

This fault can be more frequent during the first cold snap of winter when components like the gas valve or electrodes are under increased strain after being idle over 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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