BoilerFaultCodesYour boiler's burner has shut itself down for safety because it failed to light or stay lit correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner lock indicator. Feeds signal from lockout terminal on burner control box to lock out indicator on boiler control panel.
What causes this fault?
This fault occurs when the boiler's burner fails to establish or maintain a steady flame during the ignition sequence. The most common reasons are a lack of fuel reaching the burner, dirty components that cannot detect the heat, or a failure in the electrical control box that manages the firing process.
DIY fix possible
Check that your gas or oil supply is turned on and you have credit on your meter.Press the illuminated reset button on the boiler control panel.If the boiler fails to light after three reset attempts, turn it off and call a professional.
Find a Gas Safe engineer
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