BoilerFaultCodesYour boiler's internal computer has encountered a software or communication glitch that prevents it from running.
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 critical internal failure or loses the ability to communicate with its own sensors. It is often caused by a voltage spike, moisture ingress, or simply the natural degradation of the electrical components over time. Because the 'brain' of the boiler can no longer verify that the system is safe, it shuts down entirely to prevent damage.
DIY fix possible
Locate the reset button on the boiler control panelPress and hold the reset button for five secondsWait up to 10 minutes for the boiler to restart and attempt to fire up
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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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 R30 35 And 40 HE Plus 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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