"Air Purifier Fan" at work (assuming no heat transfer with the outside room) not only did not reduce indoor temperatures, but will rise. To analyze the cause of temperature rise: When fans work, due to the current through the fan coil wire is resistance, so the "Air Purifier Fan" will inevitably produce heat outwards exothermic, the temperature will rise naturally high. But why people feel cool it? Because the body's surface has a lot of sweat, when working together after fans, indoor air can flow together, so "Air Purifier Fan" will be able to promote the rapid evaporation of sweat, with "evaporation need to absorb a lot of heat," so people will feel cool.