A: The main engine should be kept horizontally and securely, with a spacing of not less than two centimeters between the ceiling and the ceiling, and a space of not less than 50 cm from the wall to facilitate maintenance.

Answer: The space above the ceiling meets the installation height requirements, the distance from the wall meets the maintenance requirements, the indoor piping piping is convenient, the supervisor can easily access the outside, and the distance between the two outdoor supervisors is guaranteed.

A: The air inlet is firmly installed and connected with the air duct. The air outlet is adjusted to a suitable opening degree.

Answer: The ground outlet flat pipe is generally laid in the floor heating insulation layer. The ground outlet can be installed on the ground or on the wall. The branch device is installed on the corner (convenient handling of the main riser). From the outside to the inside, the order is: Stainless steel outlet - Fresh air hose - PVC supervisor - fresh air hose - fresh air host - fresh air hose - pvc supervisor - branch - air flow control valve - to send air flat pipe (direct, elbow) - to ground outlet.

A: Upwind and fresh air and exhaust ducts are PVC pipes, and all are hidden in the ceiling. Installation should avoid crossover and minimize the length of the exhaust duct and the length of the hose.

Answer: The ground ventilation will lay the exhaust pipe and the new air pipe separately, avoiding the cross-influence of the air volume due to the pipeline during construction, and saving the space above the ceiling. Especially in the case where some rooms are not ceiling-mounted, the air supply from the site can still realize the diagonal arrangement of the air outlet and the air outlet, and the fresh air is sent back and forth, the airflow organization is more reasonable, and the comfort is higher. However, the cost is 20%-40% higher than the air supply.

答：用PVC大小头连接。变径后管径的大小根据风量和风速确定。

A: Adjustable air outlets are generally selected. When the air volume is uneven, the air volume of each room can be adjusted. The air outlet type can be selected according to the air volume and the wind speed.