BoilerFaultCodesYour boiler has experienced an internal communication failure or a software glitch on the main control board.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal error.
What causes this fault?
This fault occurs when the boiler's central brain loses the ability to communicate with its own internal components. The most common reason is an electrical failure within the main control board or a loose connection in the wiring harness that prevents data from flowing correctly. Essentially, the system has detected a software glitch or hardware malfunction that makes it unsafe to continue operating.
DIY fix possible
Press and hold the reset button for five secondsTurn the power supply to the boiler off at the fused spur and back on againWait 5 minutes to see if the display returns to normal
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 F0 — no call-out fees, no surprises.
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Worcester Bosch 29 HE Conventional 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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