BoilerFaultCodesYour boiler has tried and failed to light the flame several times, so it has shut itself down for safety.
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 - After five attempts (possibly due to air in the gas supply) it will lockout
What causes this fault?
This fault occurs when the boiler cannot detect a stable flame after several attempts to fire up. It is often caused by a lack of gas reaching the burner, a worn-out spark electrode that can no longer create a light, or a dirty sensor that fails to tell the boiler the flame is actually lit.
This issue can occur more frequently during the first cold snap of autumn when components that have been idle all summer suddenly fail under the strain of constant use.
DIY fix possible
Check that your gas meter is turned on and you have credit (if using a prepay meter).Check if other gas appliances, like a hob, are working to confirm gas supply.Turn the selector switch to the 'Reset' position, hold for a few seconds, then release.
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 — 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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