The aim of this paper is to show the authors proposal for steady state numerical simulation of Vapour-Compression Refrigerating Systems (dry expansion, liquid overfeed systems, ...). The developed tool allows using different levels of simulation for some elements (compressors, pipes, etc.) as well as the possibility of use different kind of expansion devices. A verification study for a steady state regime is presented analysing also influence of mesh density and of the numerical accuracy. A validation study for steady state regime is shown. Some computational results for steady state regime are also presented to provide an overview of the level of detail given by the model. A set of parametric studies is finally given to evaluate the influence of some boundary conditions (environmental temperature, secondary inlet temperatures, etc.).