The silent air supply fan adopts special sound-absorbing materials and technologically advanced hardware accessories. The bi-directional suction type Chiba turbine design can provide different air volumes according to different spaces, removing moisture, dust, and odors, thus making indoor air pure and comfortable; The air supply fan discharges the polluted air from each room, while fresh air is sent into the room through the natural air inlet installed on the wall. According to the size and number of rooms, the silent air supply fan is equipped with different air volume models to meet different needs.