BoilerFaultCodesYour boiler's internal computer brain has encountered a processing error and can no longer control the heating safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Software Error
What causes this fault?
This fault occurs when the boiler's control board suffers a critical internal memory failure or a corruption of its operating software. Over time, heat stress and electrical wear can damage the delicate microchips on the circuit board, making it impossible for the 'brain' to process safety commands. The most common reason is simply age-related components failing, meaning the board can no longer communicate with the rest of the boiler.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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