A charging cart assembly for transporting a refrigerant tank. The charging cart assembly including a frame assembly having a handle at an upper end of the frame assembly and two wheels rotatably mounted to the frame assembly. A swivel plate assembly is mounted to the frame assembly. The swivel plate assembly includes a tank securing device arranged and designed to secure the refrigerant tank to the swivel plate assembly. The swivel plate assembly with the refrigerant tank secured thereto has a generally upright position in which the refrigerant tank is in a generally upright position and has a generally inverted position in which the refrigerant tank is in a generally inverted position.