Dessert store in the main role of the exhaust fan is to replace the air inside, but not too much impact on the cooling effect of the air conditioning, so the exhaust fan exhaust times control in 4 times, that is, 40 square meters of the room, the floor height is counted as 3 meters, a **** is 120 cubic meters of space, the exhaust fan exhaust volume, control in 480 cubic meters per hour or so, if you are evenly distributed to install 4 exhaust fans, then each exhaust fan products like green island wind 120 cubic meters per hour, the exhaust fan should be arranged. Then each exhaust fan exhaust volume control in 120 cubic meters per hour, similar to the green island wind exhaust fan products, plastic ceiling duct exhaust fan, 120 cubic meters per hour, the unit price of 62 yuan, you if there is any other about the exhaust fan products consulting, you can contact, Jing's electromechanical science and technology, or add wx: genuin888, we will provide you with relevant product installation consulting services.