Industrial refrigerating machines

The complete definition of a refrigeration plant is the result of a logical analysis, starting from the type of application (air conditioning, freezing, refrigeration, etc.), its refrigeration balance and the thermal conditions of the ambient heat extraction and rejection media.

There are only two types of systems for distributing refrigeration energy:

• the direct system, with evaporation of the refrigerant in the evaporator-cooler of a gas, liquid or solid cooling process;

• the indirect system, with forced circulation of a refrigerant or heat transfer fluid between the production machine and the process heat exchangers.

In some cases, these two systems can solve the same problem, but with different technologies, energy consumption and economics. In other cases, on the contrary, site-specific economic and feasibility criteria will decide. For example, urban air-conditioning systems require chilled water distribution, whereas office air-conditioning systems accept direct VRV-type circuits.

In economic terms, a well-designed direct evaporation system is less expensive in terms of investment and energy consumption than an indirect system. The latter requires an exchanger-cooler for the refrigerant, implying additional cost, space and energy expenditure, on the one hand because of the temperature difference required by the exchanger-cooler, and on the other because of the energy supplied to the refrigerant by pumping and external heat inputs to the refrigerant pipes.

In the case of premises where staff are working, or where the public is staying, the use of a suitable, safe refrigerant carrier eliminates any risk of pollution or panic in the event of a refrigerant leak.

What's more, it's obvious that the refrigerant charge of an indirect system is lower, easier to contain and monitor than that of a direct circuit, geographically developed with difficult access.