"Exhaust Fan" before installation should be carefully examined whether the fan intact, each fastener bolts loose or fall off, whether the impeller collision hood. Carefully check the fan louvers or during transport without deformation damage. When you install the selected air environment, the opposite should be noted that the outlet can not have too much of an obstacle within 2.5 -3M. After installation is complete, check the internal fan is left legacy tools and debris by hand or toggle lever blades, check if there are too tight or collision, the availability of goods not interfere with the rotation of the anomalies before trial operation. Operation where there is vibration or fan motors are "buzzing" abnormal sound or other abnormal phenomenon should stop to check, to be repaired and then start to use.