High Lockout
Detection Fault on Ideal Concord CXA 40-120

Your boiler is failing to start because it cannot successfully ignite the gas after several attempts.

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 tries to light the gas but cannot detect a stable flame, causing the system to shut down for safety. The most common reasons are that the spark isn't strong enough to ignite the fuel, the sensors are too dirty to 'see' the flame, or the gas valve isn't opening correctly to let fuel into the burner.

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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