The overall structure is made of high-quality galvanized steel plate with spray coating treatment, which has good corrosion resistance Adopting the method of replacing the filter screen on the bottom, with a snap on design, the filter screen can be replaced without the need for tools Adopting efficient and silent DC motor combined with low-noise silent wind turbine, low noise and low energy consumption The machine adopts a micro positive pressure design, where the fresh air volume is greater than the exhaust air volume, the indoor air pressure is higher than the outdoor air pressure, and the polluted outdoor air cannot enter the indoor environment The DC machine adopts a primary effect+high-efficiency composite filter, which efficiently filters PM2.5 The machine adopts graphene high-efficiency heat exchanger, which has a long service life and high heat transfer efficiency