BoilerFaultCodesYour boiler's internal computer has encountered a glitch or a hardware failure and can no longer communicate with the rest of the system.
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 suffers a critical internal communication failure or a physical component burnout. It is often caused by long-term heat exposure degrading the electronics or an electrical surge that disrupts the board's ability to process data. In some cases, loose or damaged internal wiring can also prevent the 'brain' of the boiler from talking to the sensors and valves.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F0 — no call-out fees, no surprises.
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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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