Preservation apparatus particularly for perishable products at a preset temperature

An apparatus particularly for preserving perishable products at a preset temperature, which comprises a chamber (3) which is delimited by thermally insulating walls and accommodates heat exchanger means (5). The heat exchanger means (5) comprise a heat accumulator (20,10,11) which has at least one inner tubular element (11) for the passage of a refrigerating fluid and at least one outer tubular element (20) which surrounds the at least one inner tubular element and forms with it an interspace for containing a heat capacity mass. The outer surface of the outer tubular element defines the surface for heat exchange with the air inside the chamber.