Under normal circumstances, the exhaust should first cut off the air supply local reporting, so the combustion air fan, Lingwu exhaust fan, but in accordance with the "high level of civilian health plan made nuisance fire standards" (GB50045-95,2001年版) 8 .4.11 bars and "car database, repair garages, brake library planning hinder fire standard" (GB50067-97) defined in 8.2.7, the senior civilian health set up machine-made underground chamber and exhaust of cars library There was an opening of no direct dispersion hinder fire district to the outside, when setting machine exhaust system, exhaust fan manufacturers, Hou is set to be the same when the air supply system. Air system blower and send damper linkage fire should start to produce a positive pressure area, smoke exhaust before signing out. Two-speed exhaust fan and exhaust mechanical electron source shall request the fire power supply. The following diagram (two-speed fan control panel) SA usually versatile switch is in their own situation, the same as basically speaks usually exhaust fan application, both low-speed operation. When the fire generated, K closed, KAl power, should the case exhaust fan in the situation, the normally closed contact KAl Chu soldiers cut off KMl exchanges winding circle, KMl off, KMl normally closed contacts closed, communication device KM2, KM3 is turned on, forcing the exchange to rapidly exhaust fan situation. When the duct temperature reached and the realization of 280 ~ C, a temperature valve fittings hinder fire behavior, exhaust fan maintenance, close-valve, YE off, KM2, KM3 de-energized, the fan out of operation. When the all-around at the manual switch SA situation, as to complete the high and low exchange, exhaust fan selection, although this time the fire control linkage signal at very IMPACT lose effect, but after the emergency control can be achieved and realized the same attempt. Exhaust fans axial fans: air flow along the axial movement of the fan impeller. Centrifugal fan total pressure is large, the motor isolated from the hot gas fumes. Not easily damaged. Small axial fans, in general, at the high temperature gas fumes to go through the motor, easily damaged. Kitchen generally recommended to use a centrifugal fan. Centrifugal fans and former stars to the multi-leaf impeller and backward impeller. Comparison to the front wheel and rear wheel advantages :() opt for a lower speed (low noise), smaller diameter can get a larger air volume total pressure. Forward impeller disadvantages: low efficiency, high energy consumption, easy cleaning cleaning. After the impeller advantages: high efficiency, energy saving, easy cleaning cleaning. After disadvantage compared to the impeller to the impeller) to be given equal air flow and total pressure required for high speed (and therefore noise), and a larger diameter front :(. Exhaust fan maintenance, Chenyu air conditioning (certified), exhaust fan Lingwu City by Wu Chen-yu air-conditioning Limited. Wu Cheng Chen-yu air-conditioning Co. (www.wccykt.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 ??? Chen Yu-conditioned in leadership with the staff warmly welcome all inquiries negotiations to create Chenyu air conditioning better future.