BoilerFaultCodesYour boiler is failing to start because it cannot successfully ignite the gas after several attempts.
Book a Gas Safe engineer within 24–48 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.
DIY fix possible
Check that your gas emergency control valve is turned onIf you have a prepayment meter, check that you have sufficient creditCheck that other gas appliances in your home, such as a hob, are working correctlyPress the reset button on the control panel to try once more
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Detection Fault — no call-out fees, no surprises.
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Ideal Concord CXA 40-120 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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