To reduce a manufacturing cost by facilitating manufacture of a casing and simplifying a mold for manufacture.

A water storage tank 22 installed in an outside case 12 formed in a rectangular parallelepiped shape stores water. A circulating pump 26 for circulating the water in the tank 22 to a water filtration generator 44 is operated to pass the water through the generator 44, thereby clarifying the water. A Peltier element 28 heat exchanges the water passing a cooling pipeline 32 to cool the water in the tank 22. And, heat after heat exchanging by the element 28 is discharged out of the element 28 via a fan 40. Heats of the fan 40, pump 26, water supply pump 60 and circuit board 40 are radiated from windows 72, 74 perforated at a back surface of the case 12.