BoilerFaultCodesYour boiler has stopped working because it cannot light the burner, which most often happens when your oil tank is empty or there is an issue with the oil supply.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner lockout condition. Check the oil supply/level in the tank.
What causes this fault?
This fault happens because the burner has failed to establish a flame after several attempts, causing the boiler to shut down for safety. The most common cause is simply a lack of fuel reaching the burner, either because the oil tank is empty or there is a blockage in the supply line. It can also be caused by a dirty sensor that can no longer 'see' the flame or a worn-out nozzle that isn't spraying fuel correctly.
This fault is particularly common during the first cold snap of autumn when oil levels may be low following the summer or when thickened 'waxing' occurs in the oil during extremely cold winter spells.
DIY fix possible
Check the level of oil in your fuel tank to ensure it hasn't run dry.Verify that the oil supply valves to the boiler are fully open.Press the reset button on the control panel once to see if the burner restarts.
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