The fresh air system is not a smog in foreign countries.

The foreign fresh air system market, especially in Europe, Japan, the United States and other places, is very mature. In these countries and regions, although the outdoor air quality is far better than the domestic one, there is no smog, but the popularity of the fresh air system is very high, even Laws and regulations mandatory installation!

The fresh air system originated in Europe. It is said that as early as 1958, low noise and high static pressure blowers were introduced for various places. Since the environment emphasized energy conservation at the time, a large number of buildings were designed with great emphasis on air tightness, although Significantly improved in terms of heat insulation, heat preservation, sealing, etc., but it also causes serious shortage of indoor ventilation rate, causing headaches, dry cough, dry and itchy skin, dizziness and nausea, difficulty in concentration and sensitivity to odor, etc. Symptoms, known as 'pathogenic building syndrome'.

Generally speaking, to solve the problem of indoor air turbidity, window ventilation is a good method, but once the window is opened, it will lead to the loss of indoor and outdoor thermal energy, and at the same time destroy the overall insulation system of the building, and also cause outdoor dust and noise to enter. Indoor. So the contradiction between the switch window has not been solved. It is for this reason that people began to study and discuss the impact of indoor air quality on human health, pollutants and their sources, and feasible solutions.

In the end, in the economy, developed technology and quality of life in Europe, there has been a residential microcirculation air replacement system, also known as the fresh air system. It is a continuous and able to control ventilation path, through the performance of the fan and airflow control system , so that the replacement of fresh air is completely controlled.

In the absence of window opening, the indoor dirty air is continuously discharged 24 hours a day, and outdoor fresh air is introduced, and the air volume is effectively controlled. In the 1970s, more than 90% of new homes in Spain were equipped with fresh air systems; ASHRAE has developed the 'Indoor Air Quality Ventilation Specification'; in Germany, the residential ventilation system has become an indispensable part of the integration of buildings; in 2000, the installation of fresh air systems throughout the European Union has become a regulation.

From the experience of these countries and regions, their fresh air system has such a high installation rate, mainly for several reasons: economic and material life basis, basic layout of the house, outdoor noise, indoor air conditioning use, residents' living habits, etc. .