An air handler and a fan module for an air handier are provided. The fan module may include a plurality of box frames that form a framework of at least one fan box; a plurality of safety nets coupled to the framework of the at least one fan box formed by the plurality of box frames to form surfaces of the at least one fan box; and at least one box frame connector that interconnects neighboring one of the plurality of box frames to form the framework of the at least one fan box, wherein the at least one box frame connector has a fan box connection end configured to assist connection of the neighboring one of the plurality of fan boxes. As such, manufacturing costs may be reduced due to reduction in a number of components, and assembly time may be remarkably reduced due to a reduced number of assembly operations. This advantageously results in reduced labor cost and enhanced air conditioning efficiency.