副烟道务必保留
The auxiliary flue must be reserved
每家的厨房里都有烟道，同时烟道也有主副之分，主烟道贯穿整个楼体，而副烟道是相对独立的。一般家里的油烟会先到副烟道里，然后再通过隔板上的孔进入主烟道，这样可保证每户的油烟是隔离开来的。而如果将副烟道直接连接主烟道，就会由于压力过低而导致倒烟或串烟现象。
Every kitchen has a flue. At the same time, the flue can be divided into main flue and auxiliary flue. The main flue runs through the whole building, and the auxiliary flue is relatively independent. Generally, the oil smoke in the home will go to the auxiliary flue first, and then enter the main flue through the hole on the partition, so as to ensure that the oil smoke of each household is isolated. If the auxiliary flue is directly connected to the main flue, it will cause smoke pouring or smoke stringing due to low pressure