BoilerFaultCodesYour boiler has stopped running for safety reasons and needs to be manually restarted to try and get your heating and hot water back on.
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 (identified by flashing lights on facia). Can only be cleared by using the facia reset button (press for at least one second).
What causes this fault?
This fault occurs when the boiler attempts to light the burner but fails to detect a stable flame. The most common reasons include a lack of gas reaching the unit, worn-out spark components that cannot ignite the fuel, or a sensor that is too dirty to recognize that a flame is actually present.
This issue often surfaces during the first cold snap of autumn when the boiler components are put under sudden strain after being inactive throughout the summer.
DIY fix possible
Locate the reset button on the front control panel.Press and hold the reset button for at least one second.Wait for the boiler to restart; if the light stops flashing, the boiler should resume normal operation.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Slow flash — no call-out fees, no surprises.
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Worcester Bosch 24CDi BF 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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