A fan powered box is a type of air distribution system that uses a fan to draw in outside air and then circulate it throughout the building. It is compatible with Aerfoam insulated ducts and features 16 Air Excellent AE34C duct connections. With DBOX adaptors, it can connect to any. There are many accessories in the fan distribution box, such as low-voltage electrical appliances, fuses, AC contactors, residual current action protectors, which are all important parts of the fan distribution box. The following are several common cooling methods for distribution boxes: Natural heat dissipation:. Provides distribution boxes for building fans and air conditioning systems to ensure efficient operation of equipment and stability of power supply.