High Lockout
Detection Fault on Ideal Concord CXC 48 116

Your boiler has tried to start up several times but cannot establish a stable flame to begin heating.

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 fails to light after 5 attempts

What causes this fault?

This fault occurs when the boiler's control system cannot confirm that a flame has successfully ignited after five attempts. It is usually caused by a worn-out ignition component that fails to create a spark or a faulty sensor that cannot detect the heat of the fire, leading the boiler to shut down for safety. In some cases, it may also indicate that gas is not reaching the burner at the correct pressure.

This fault is more frequent during the first cold snap of autumn when internal components that have been dormant all summer struggle to operate correctly upon restart.

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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