BoilerFaultCodesYour boiler has switched itself off for safety and needs to be manually restarted to identify the specific fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler is in lockout for a specific error. Display will show a number after the “L” to indicate which error is detected.
What causes this fault?
An 'L' code indicates that the boiler has encountered a safety issue and has 'locked out' to protect the system. This usually happens when the boiler fails to ignite or keep a flame lit, which can be caused by problems with the gas supply, a worn-out ignition lead, or a fault within the internal control board. To find the exact cause, you must look for the number that flashes immediately after the 'L' on the display.
DIY fix possible
Locate the mode dial on the front of the boilerTurn the dial to the 'RESET' position and hold for 2 secondsRelease the dial and observe the screen for a new code following the 'L' (e.g., L2 or L5)
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A boiler cover plan would cover faults like L — no call-out fees, no surprises.
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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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