Abstract: An air duct machine including a cabinet, an electric control box, a heat exchanger and a centrifugal fan; the electric control box, the heat exchanger and the centrifugal fan are all disposed inside the cabinet, one of side panels of the cabinet is provided with a return air vent and an air outlet, the electric control box is disposed close to the return air vent, the centrifugal fan is disposed close to the air outlet, and the heat exchanger is disposed between the electric control box and the centrifugal fan. This improves the selectivity and flexibility of installation of the air duct machine, and facilitates maintenance. The air duct machine can have an ultra-thin design when installed in the ceiling or wall, so that the installation space is reduced. Moreover, the airflow direction will not change due to the change of the installation method.