BoilerFaultCodesYour boiler has failed to light the gas flame and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition LOCKOUT
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to detect a sustained flame after several attempts. The most common reason is a build-up of carbon on the ignition probes or a failure in the component that delivers gas, which prevents the burner from firing safely. As a result, the system shuts down completely to prevent unburnt gas from accumulating inside the unit.
This fault is more frequent during the first cold snap of autumn, as internal components like the gas valve can seize up after being inactive throughout the summer.
DIY fix possible
Check that your gas pre-pay meter has credit and the gas emergency control valve is open.Turn the control knob to the 'Reset' position for a few seconds, then back to the on position.If you have other gas appliances like a hob, check if they are working to confirm gas supply is reaching the property.
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 (Red) On, Burner (Green) Off, Mains (Green) On — no call-out fees, no surprises.
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Potterton Performa SL HE 9 2 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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