BoilerFaultCodesYour boiler has detected a general internal fault and has locked itself out to prevent damage or safety issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault condition
What causes this fault?
This fault occurs when the boiler's internal computer identifies an electrical or mechanical failure that prevents it from firing safely. The most common cause is a failing control board that can no longer communicate with parts like the fan or ignition system, leading the boiler to shut itself down for safety.
DIY fix possible
Press and hold the 'Reset' button for approximately 5 seconds until the light stops flashing.Wait for the boiler to complete its restart sequence.Ensure your gas supply is active and you have credit on your meter.
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 Indicator light flashes fast (constant interval) — 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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