Water Filters

Water filters reduce the carbonate hardness in the water, thus avoiding scale deposits on crucial areas, including valves and copper pipes. electro, stat, when changed at regular intervals which can coat the element, block the micro channels of the coffee group, the pressure build-up. 

PURITY C water filters prevent lime. 
In best case scenarios lime build up can cause a reduction in steam preventing cappuccino froth and increase your electrical consumption, in worst cases it can block the coffee group stopping the coffee altogether.