BoilerFaultCodesYour boiler has stopped itself for safety because it failed to light or stay running, and it needs to be manually reset.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition failure or safety interruption requiring manual reset of the lockout switch.
What causes this fault?
This fault happens when the boiler tries to start but fails to detect a constant, safe flame. It is usually caused by a worn-out ignition spark, a blocked pilot light, or a gas valve that is no longer opening correctly to let fuel into the burner.
DIY fix possible
Locate the lockout reset button on the control panelPress the button or wait 10 seconds and turn the control knob to 'Off' then back to 'On'Check that your gas supply is active and credit is on the meter
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Lockout light on — no call-out fees, no surprises.
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Ideal Concord Super Series 4 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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