Can it be ventilated in the cold weather in Northeast China?

Yes According to relevant public information, if the doors and windows are closed all day in winter, the indoor air will not circulate, and breathing such air for a long time is not good for your health. In cold winter, windows should be properly ventilated. Winter in the northeast is very cold, nearly MINUS 20 degrees. If you want to open the window and smell it, you can do it. Ventilation is a technology that uses natural or mechanical methods to make the wind pass through and reach the room or closed environment without obstacles, thus creating a healthy and safe air environment.