BoilerFaultCodesYour boiler's computer brain has suffered a serious internal glitch and is unable to communicate with its own sensors or controls.
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 main control board experiences a total communication failure between its internal components. It is often caused by an electrical surge, a moisture-related short circuit, or simply the natural degradation of the aging electronics inside the unit. Because the 'brain' can no longer process safety data, the boiler shuts down entirely to prevent any unsafe operation.
DIY fix possible
Locate the reset button on the front control panelPress and hold the reset button for five secondsRelease the button and wait for the boiler to restart
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A boiler cover plan would cover faults like F0 — no call-out fees, no surprises.
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Worcester Bosch Greenstar 25HE 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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