Unfortunately, the quality of fresh air outside the house is not always healthy or comfortable breathing, even in today’s urban environment and sometimes in rural environment. Pollution, pollen, dust will have a serious impact on your long-term health and everyday comfort. Natural ventilation is sufficient for exchanging air because of the large temperature difference between indoor and outdoor. The movement of the air can be fine-tuned according to some design techniques. However, in many climates, air temperature does not occur because the temperature difference (especially the middle temperature) is too low. …
