Have a 5500 system Europa model (220V) and just purchased a USA system for spares because sooner or later I need spares. The USA system works fine. Just wondering if anyone know the main difference. Is it only the power supply 110 vs 220V. Is there any differences exept for this e.g. if I take the cooling fan form the USA model and put into my unit it will work. Or if I take a complete board from the USA unit and replace in my unit. Will it work or did I do a mistake buying the USA version as spares? Regards Henry