BoilerFaultCodesYour boiler has experienced an internal computer error and cannot safely operate the heating or hot water until the main control parts are checked.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: internal failure - electronic
What causes this fault?
This fault occurs when the boiler's internal computer brain, the Printed Circuit Board, can no longer communicate correctly with its other electronic components or loses its programming. It is physically caused by a failure of the microprocessors or electrical circuits on the board, which prevents the boiler from running its safety checks. Without this data, the system shuts down immediately as it cannot verify that it is safe to ignite.
This fault can sometimes be triggered by power surges or electrical interference during winter storms, but it is generally a hardware failure that occurs at any time of year.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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