BoilerFaultCodesYour boiler's internal computer memory is not communicating correctly with the main control board, preventing the system from starting.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: INCORRECT EEPROM SIGNATURE EEPROM not recognised by the processor
What causes this fault?
This fault occurs when the boiler's central brain fails to read the permanent memory chip that stores its specific operating instructions. It is usually caused by a hardware malfunction within the electrical circuitry or a communication failure between the memory chip and the control board. Because the boiler cannot verify its own identity or settings, it shuts down for safety reasons.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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