The water is put into a special tank or boiler that super heats the water and changes it into a hot "dry" mist or vapor. Therefore the name - vapor system . The unique benefit of this system is that it produces a low moisture, high-temperature vapor that carries only about 6 percent water.
Since steam and water do come out of the wand, it, too, will have mineral deposits and the descaling will help in preventing clogs. Poor Results from Temperature Factors The Portafilter and Filter – When the espresso is brewed, the temperature of the liquid coming out of the machine, before it hits the coffee, is around 200°F (generally