Integration of new and existing technologies for thermal management will be required to meet the challenges associated with the increased need for an efficient, lightweight, heat rejection system. Subsystem design requirements, such as thermal and mass management, must be brought into me design cycle to establish an optimal configuration. This paper provides a parametric analysis that determines a range of parameters under which a proposed system becomes viable from a weight management standpoint. The analysis can be applied to essentially any space-operated thermally-actuated heat pump with power and refrigeration subsystems. By applying the techniques demonstrated in this paper, designers can identify and optimize conceptual configurations during the initial prototype development stages to reduce payload weight and increase financial savings.