The cylinder of the vertical condenser is installed upright on the water storage tank. After the cooling water enters the pipeline from the top water distribution tank, it flows downward in a film like manner along the wall, and the flowing water is concentrated in the pool below. The refrigerant vapor enters from the upper part of the cylinder, releases heat, and condenses into a liquid outside the pipe, which is discharged from the bottom. Cooling water goes through the tube side, while refrigerant goes through the shell side. That is, high-temperature and high-pressure refrigerant vapor cools, condenses, and converges on the outer surface of the heat transfer tube to the shell guide nozzle.