"220V Cooling Fan" when the operation is changed as in the case of heat, operate at a slower speed, the fan will have less noise and consume less energy. In most of the design requirements, after "220V Cooling Fan" Speed operation hours air temperature is usually lower than the maximum design temperature values. Under normal circumstances, low-speed operation of the cooling fan can be enough to complete its work. However, in the selection and installation should be considered: first, the choice of "220V Cooling Fan" must be able to provide sufficient amount of exhaust (speed), under the high temperatures of the hot air inside the cooling device; when the temperature is relatively low and hot air is less time to do the opposite of work.