"Industrial Ventilation Fan" fan selected must be able to provide enough exhaust volume (speed), under the high temperature of the cooling device inside the hot air; When the temperature is relatively low and less when hot air is to do the opposite work. Secondly, "Industrial Ventilation Fan" position sensor installation choices should pay attention to the sensor in the proper position, try to make the sensor can be clamped directly to the surface to be cooled. In the cooling fan operation, a temperature-controlled cooling fan will run at a faster rate if higher temperature feeling when; while at lower temperatures, it will operate at low speed; "Industrial Ventilation Fan" among these high and low, the cooling fan speed is hardly changed with temperature.