"220V Cooling Fan" operating conditions is accompanied by heat and changed to slow speed operation, the fan will have less noise and consume less energy. In most of the design requirements, the fan speed after running for several hours in the air temperature is usually lower than the maximum design temperature value. Under normal circumstances, low-speed operation of "220V Cooling Fan" can be enough to complete its work. However, in the selection and installation should also be considered: First, the choice of fan must be able to provide sufficient amount of exhaust (speed), under the high temperatures of the hot air inside the cooling device; when "220V Cooling Fan" temperature comparison time low and less hot air is to do the opposite of work.