BoilerFaultCodesYour boiler’s internal computer has encountered a critical communication error and can no longer process instructions.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's central control board suffers a hardware failure or a total breakdown in communication with its internal components. It is often caused by a sudden electrical surge that damages the sensitive microprocessors, or by moisture getting into the casing and short-circuiting the electronics. Essentially, the 'brain' of the boiler has stopped working, meaning it can no longer safely control the gas valve or ignition process.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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