BoilerFaultCodesYour boiler has detected a internal problem with its electronic control system and has stopped running 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: Internal fault
What causes this fault?
This fault occurs when the boiler's central brain, the printed circuit board, fails its internal safety checks or loses communication with the sensors. The most common reason is electrical degradation of the components over time, or a loose connection in the wiring harness that prevents the system from operating safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 Fast flash / Flashing — 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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