The fresh air system is simply an indoor air exchange system that discharges indoor polluted air to the outside and simultaneously sends fresh outdoor air to the room. Through the cyclic exchange of air, the purity of indoor air is achieved, and human health is guaranteed. The detailed function of the fresh air system can be divided into 1. Provide fresh air. 365 days a year, 24 hours a day, every day, we provide fresh air to the room. We can enjoy the fresh air of nature without opening the window to meet the health needs of the human body. 2. Repel harmful gases. Effectively remove various unhealthy or harmful gases such as oily smoke, odor, CO2, cigarette smell, bacteria, viruses, etc., to avoid the harm of second-hand smoke to children, lover and old people at home. 3, anti-mildew and odor. Exhaust the dirty and dirty air in the room, eradicate the odor, prevent mold and bacteria, and help to extend the service life of buildings and furniture. 4. Reduce noise pollution. No need to endure the turmoil caused by the opening of the window, making the room quieter and more comfortable. 5, dustproof. Avoid opening a window to bring a lot of dust, effectively filtering the outdoor air, and ensuring that the air entering the room is clean. 6. Reduce energy consumption. Continuous operation throughout the year, the power consumption may not be as good as your refrigerator, and it can recover the energy from the outdoor air, minimizing the loss of cold and heat sources in the summer or winter, reducing the energy consumption of the air conditioner. . 7, safe and convenient. Avoid property and personal safety hazards caused by window opening. Even if there is no one at home, it can automatically ventilate. Through the introduction of the above effects on the fresh air system, it can be seen that the fresh air system is the most effective way to improve indoor air quality and achieve indoor ventilation and ventilation, which can reduce energy consumption, protect health, dust and noise, and improve life comfort. In developed countries, the fresh air system has become an essential supporting facility for residential development.