Lower global warming potential (GWP) refrigerants and blends have been introduced and are in broad use in a variety of applications. In most cases these lower GWP alternative solutions achieve the Montreal protocol goals, but debate continues if new technologies can minimize the impacts of refrigerants. Hydrocarbon refrigerants are among proposed solutions and are seeing increased interest in their application for larger capacities. Hydrocarbon safety due to their highly flammable characteristics limits their applicability to chiller platforms for higher capacity. This paper investigates the impact of chiller system designs that make use of secondary fluids which affect both capacity and efficiency compared to direct expansion (DX) vapor compression systems.