Refrigeration exchanger, method for control thereof and cooling installation including such exchanger

In a refrigerating exchanger for a refrigeration facility, comprising, in a circuit, a refrigerating or heat removing fluid circulation assembly connected to a heat exchanger assembly having a large surface area;

• said assemblies being disposed in the form a battery with several layers and several rows arranged in a plurality of similar elements, connected in parallel, and separated by partitions which provide heat insulation and collection of water resulting from defrosting operations, each element including at least one layer, a respective inlet and outlet forming part of the circulation assembly, the improvement wherein the battery comprises at least three elements, and a single expansion valve common to the elements, connected on a single branch of the circuit and located upstream from the inlet of the elements, a plurality of branches connected in parallel and located downstream from said expansion valve;
• each of said elements connected to one of the branches connected in parallel having a refrigerating capacity which is a fraction of the entire exchanger nominal output, such that at a given time of the exchanger operation at least one of the elements can be in a defrosting mode, while at least two of the elements can be in a refrigerating mode, said elements alternating between the defrosting mode and the refrigerating mode.