High Lockout
LF on Ideal Classic FF

Your boiler is failing to ignite and has locked itself out for safety after several unsuccessful attempts to start.

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

The boiler does not light after 3 attempts

What causes this fault?

This fault occurs when the boiler tries to light the flame several times but fails to detect a successful ignition. It is usually caused by a worn-out ignition component that can no longer create a spark, or an issue with the gas supply preventing fuel from reaching the burner.

This issue often surfaces during the first cold spell of autumn when the boiler is worked harder after being mostly idle during the summer months.

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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