Abstract In this study, a very simplified dynamic lumped model for the simulation of small-scale single-temperature vapor compression refrigerators working between two thermal sources with finite thermal capacity is presented. The model is compact enough to be employed in actual regulation systems, but adequate to describe the basic underlying physical phenomena relevant to the transient response of the refrigerated cell. The dynamic behavior of the system is simulated taking into account the main heat capacities involved in the heat transfer processes between the system, the refrigerating fluid and the outside. The numerical model has been validated by comparing the calculated results with transient experimental data coming from an instrumented chest-freezer. After a steady state tuning phase, the model was able to predict the transient temperature response of the cell with good accuracy.