Evaporator for refrigeration systems

An evaporator for refrigeration systems, comprising:

• a set of tubes arranged in series, spaced and parallel in relation to each other, carrying a refrigerant fluid;
• and
• a plurality of fins, which are incorporated to and trespass the set of tubes, arranged in multiple rows and extending transversally to the direction of a forced airflow that is forced to pass through the evaporator and through an environment to be refrigerated, each row being formed by a plurality of fins arranged substantially parallel to the direction of the forced airflow and incorporated to at least one of said tubes wherein the fins, which are incorporated to the first and second tubes according to the direction of the forced air flow, are spaced from each other by a larger distance, when they are operatively associated with a refrigerating environment, and by a smaller distance, when they are operatively associated with a freezing environment, said distances decreasing at each two subsequent tubes, until reaching at least the third tube, said distance being then maintained at a minimum value for the other subsequent tubes.