The paper describes an analytical tool (a digital computer program) developed to facilitate the synthesis of air-conditioning system components to minimize energy expenditure for a given cooling capacity. The synthesis is performed by allowing the variation of component properties within a system and the introduction of new components into unique systems. To assure the practical applicability of the developed algorithm, the system components are selected entirely from production series of various manufacturers. The components' models appear in the form'of algebraic functions, typically for the measured through variables (heat and mass transfer) in terms of the measured cross variables (pressures and temperatures). In addition to describing the computer program as a whole, the paper includes a detailed example showing how the optimization procedure was applied to an existing design of a central air-conditioning system. The cost saving accrued by the optimized design, compared to the existing one, is also discussed.