Is it useful to install Changsha fresh air system?

It must be useful. Especially if there are old people and children at home, it is even more necessary to install them. The reason for this is that, first, the function of installing fresh air in our home is to purify smog PM2.5, and second, close the doors and windows for ventilation when sleeping to reduce the concentration of carbon dioxide; However, due to the immaturity of the fresh air industry, the phenomenon of shoddy, illegal construction and cutting corners is very common, and customers can't tell. After the fresh air was installed, it was not tested, and they didn't know how to test it. Most fresh air has no effect at all. Secondly, carbon dioxide exceeds the standard because the HVAC company designed and constructed is unprofessional and irregular. Only after we install fresh air can we avoid the following problems and ensure the good effect of installing fresh air;

First, I don't understand the design specifications, and the air volume configuration is not up to standard;

Second, in order to save costs, deliberately reduce the air volume configuration of the main engine;

Third, installation and construction, illegal reduction of duct diameter, large air loss.

Among the fresh air brands, oxygen wind is recommended.