BoilerFaultCodesYour boiler has experienced an internal electrical communication error, which means the main control box cannot talk to the internal components correctly.
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 – electrical connector contacts or programmer interface module – check ignition leads are not loose.
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to send or receive data from its internal operating modules. It is typically caused by a loose electrical connection, worn out ignition leads, or a mechanical failure within the 'brain' of the unit that prevents it from coordinating the heating process safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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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 CDi Classic 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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