Exhaust fan choice points: 1, the exhaust fan chosen as the main control parameters temperature, air flow, total pressure, efficiency, noise, electrical power, speed and shaft power. 2, the exhaust fan at a temperature not higher than 85 ℃ conditions should be long-term normal operation. 3, exhaust fan shall ensure that: When the transmission medium at a temperature of 280 ℃ continuous work 30min exhaust fan, and the medium temperature cooled to ambient temperature still continuous running. 4, at rated speed exhaust fan total pressure, in the work area, fans of the measured pressure curve with the description given in the curve should meet the following requirements: 5, axial-flow exhaust fan in the regulations, corresponding to the pressure deviation of ± 5%. 6, the centrifugal exhaust fan at a predetermined flow rate of the exhaust fan noise, corresponding to the pressure deviation of ± 5%. 7. A sound level than the noise limits should be consistent with the provisions of JB / T8690-1998 the exhaust fan in the specification given operating point under. 8, exhaust fan can be an ordinary or special steel centrifugal fan axial exhaust fan. Exhaust fan specifications according to "fire protection design of tall buildings" in the regulations. The minimum air volume exhaust fan 7200m / h, the maximum air flow should not exceed 60000m / h (refers to a partition of the maximum exhaust air volume). 9, exhaust fan flow should be required to increase airflow value of not less than 10% to 20% of the surplus amount. 10, pressurized smoke exhaust fan pressure value shall be calculated loop system is the most unfavorable exhaust fan use, and to ensure that the value of residual pressure in the stairwell 40 ~ 50Pa. The residual pressure value inside the front room, shared room, fire elevator room, refuge floors, etc. 25 ~ 30Pa. 11, fire exhaust fan should be consistent with the current standard JB / T10281-2001 "fire exhaust fan technical conditions." 12, fans should exhaust system individually. Exhaust fan should be in the same position or an upper layer of smoke region. Exhaust fan as a common mechanical equipment, it should always be maintained, so that it can be a longer service life. Fan maintenance methods are mainly the following aspects: 1, regular cleaning of the fan and tube dust, debris and the like. 2, fans keep clean the surface and use the environment. 3, to maintain adequate power capacity, voltage stability, non-phase operation; exhaust fan total pressure, the Swiss mechanical and electrical liter (certified), exhaust fan ventilation and air conditioning provided by the liter Swiss mechanical and electrical equipment factory. L Rui HVAC Electrical Equipment Factory (www.dzsrxfkt.com) is an industry leader in Shandong Dezhou, fans, ventilation equipment, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In liters Swiss electromechanical leadership with the staff warmly welcome all inquiries negotiations to create liter Swiss electromechanical better future.