"220V Cooling Fan" is a country on the gas compression and gas transportation machinery habits short, commonly referred to as cooling fans, including through the cooling fan, cooling fan drum. Gas compression and gas transport machinery is to be converted to mechanical rotation energy and kinetic energy of gas pressure and gas transportation out machinery. Scale "220V Cooling Fan" manufacturers are generally small nature of their industry, ventilation and air conditioning of large enterprises seldom end in itself, so do heat recovery alone will not be much more business. Due to the size of the new air system manufacturers generally small, there is no scale advantages, it is difficult to reduce costs, making the new air system to the low-end residential marketing difficult. Not only is the scale of production, in the production process, "220V Cooling Fan" industry there are bottlenecks.