"Exhaust Fan" is generally used in some use environments requiring low noise and high static pressure of the occasion, in order to achieve an air circulation effect. Different fans have different sizes. When users must choose according to their actual situation to select the appropriate fan. Another point to note that this fan maintenance work is very important to determine its service life. "Exhaust Fan" Maintenance personnel must pay attention to the following points: 1, the only fan in operation before the device is completely normal. 2. The fan equipment after maintenance at start, you need to pay attention to all parts of the fan is normal. 3, periodically clear the fan and the gas pipeline inside the dust, dirt and water and other impurities, and to prevent corrosion. 4, "Exhaust Fan" repair equipment shall not be performed during operation.