PURPOSE: To minimize the size of drain pan, hence save materials, and reduce cost and weight by laying out the drain pan properly to the shape of coil and moreover mounting a coil type water cooler assembled in one piece with the drain pan when the cooler must be fixed with a fixing plate.

CONSTITUTION: In a coil type water cooler 1, heat exchange takes place between the water flowing in an outer tube 2 and the refrigerant flowing in an inner tube 3 and cooled water is obtained by way of heat exchange. In this process where the cooled water is obtained, the outer surface of the outer tube, where cooled water is flowing, is turned to a temperature equivalent to the temperature of the cooled water and drops to the dew point temperature of air around the outside and below, which produces dew condensation on the outer surface of the outer tube 2 and the dew drops. The water is collected in a drain pan 4 formed along the coil type water cooler 1 and flows down along the inclination of the coil shape and it is discharged from a drain port 7 at the lowest elevation. Furthermore, since the drain pan 4 is laid out between the coil type water cooler 1 and a fixing plate 5, it is assembled in one piece by a fixing bad 6. This construction makes it possible to minimize the side of the drain pan and enhance the efficiency of assembly work since both the water cooler and the drain pan can be assembled in one piece.