"Waterproof Cooling Fan" The main components are: AC motor. Its working principle is: energized coil in a magnetic field by the force of the rotation. Form of energy is transformed: the main electrical energy into mechanical energy, and because the coil has a resistance, so that there is an inevitable part of the electrical energy to be converted into heat. When the fan work (assuming no heat transfer with the outside room) not only did not reduce the indoor temperature, it will rise. Let us analyze a temperature rise causes: "Waterproof Cooling Fan" work, since there is a current electric "Waterproof Cooling Fan" coil wire is resistance, it will inevitably produce an exothermic heat outwards , so the temperature will rise.