BoilerFaultCodesYour boiler has stopped running because it has detected an operational fault and has locked itself out 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: Lock-out signal lamp
What causes this fault?
This fault occurs when the boiler fails to light or detect a flame after several attempts, leading the system to shut down for safety. The most common reasons include a worn-out ignition spark, a faulty gas valve that isn't opening correctly, or a communication error within the main control board.
DIY fix possible
Press and hold the reset button for 2 secondsCheck that your gas pre-payment meter (if applicable) has creditEnsure any external shut-off valves for the gas or water have not been accidentally closed
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 E — no call-out fees, no surprises.
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Ideal Mini 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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