BoilerFaultCodesYour boiler has failed to ignite and has locked itself out for safety, meaning you currently have no heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If the boiler does not light after 10 seconds, the RED lockout led is illuminated.
What causes this fault?
This fault occurs when the boiler's control system fails to detect a flame after several attempts to start. The most common reasons are a lack of gas reaching the burner, a faulty spark that fails to light the fuel, or a sensor that is too dirty to 'see' the flame once it has started.
This issue is more frequent during the first cold snap of autumn when internal components like the gas valve may stick after being dormant throughout the summer.
DIY fix possible
Check that your gas supply is turned on and other gas appliances are working.Ensure there is credit on your gas meter if you have a prepaid system.Press the 'Reset' button on the front of the boiler once to see if it restarts.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like RED lockout led — no call-out fees, no surprises.
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Ideal Boxer C 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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