1. Direct cooling or "direct expansion

Direct evaporation refrigeration systems are widely used in a variety of fields:

• small and medium-sized air-conditioning systems under 300 kW;

• cooling systems for display shelves and cold rooms in medium and large stores, with a current trend towards indirect systems;

• storage of fresh and frozen produce;

• food processing, refrigeration and freezing;

• air treatment for drying various products (kilning, plasterboard);

• cooling of various types of transport equipment: trucks, containers, refrigerated wagons, etc.

In a direct system, only one temperature difference needs to be considered: from the medium to be cooled or heated to the refrigerant....