Your boiler's internal computer memory is not communicating correctly with the main control board, preventing the system from starting.

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.