HVAC Maintenance & Repair: System Installation & Replacement: Install, repair, and replace HVAC systems, including furnaces, air handlers, condensers, heat pumps, and ductwork. Regularly required to stand and move; use hands to grasp, squeeze, finger, handle, and feel; reach, push, and pull with hands and arms; twist; reach overhead; stoop, kneel, squat, bend, and crouch.