A complete refrigeration system (CRS) including at least one heat exchanger which is designed to occupy an irregular volume to reduce the overall profile of the CRS. The heat exchanger may be a condenser or an evaporator, and includes a substantially solid body made of a thermally conductive metal, plastic, or other material. A plurality of fluid and refrigerant passageways are defined substantially within the solid body for conducing fluid and refrigerant, respectively, through the solid body and facilitating the transfer of heat between the fluid and refrigerant. Also disclosed is a method wherein the spatial orientation of each passageway is optimized with respect to all of the other passageways and the walls of the solid body by determining the relative distance of each passageway from all of the other passageways and the walls of the solid body at a plurality of points along each passageway, followed by adjusting the spatial orientation of the passageway accordingly.