BoilerFaultCodesYour boiler has tried to light several times but failed, so it has shut itself down 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: Ignition lockout
What causes this fault?
This fault occurs when the boiler has attempted to ignite the gas several times but failed to detect a successful flame. The most common reasons include a lack of gas reaching the unit, worn-out spark electrodes, or a blockage in the flue system preventing the burner from firing safely.
This fault is more common during extreme cold spells, as the external condensate drainage pipe can freeze and back up, preventing the boiler from completing its ignition cycle.
DIY fix possible
Check if your gas credit has run out or if other gas appliances in your home are workingCheck that the condensate pipe (the white plastic pipe outside) hasn't frozen in cold weatherPress and hold the reset button for 5 seconds until the light stops flashing
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 Slow flash (normally off, flashes on) / Flashing (reset required) — no call-out fees, no surprises.
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Worcester Bosch Greenstar 24i Junior 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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