During the free cooling chiller work, thermal energy is exchanged: from the object that is being cooled, it passes into the environment. In this case, the process itself can go both naturally, without the participation of any devices. In the second case, heat is redistributed between the object, which is hotter, to the object with a lower temperature. To achieve this result, additional energy is required.
How Does Free-cooling Process Occur?
A free cooling system is necessary for the operation of the compressor. Its task is to form zones with different pressures in the hydraulic circuit of the cooling device – lower and higher. This makes it possible to create conditions under which the refrigerant can pass from the liquid to the gaseous phase. So, one of the circuit sections becomes the place where heat energy is absorbed, and the other – where it is spent on the condensation of the refrigerant.
There are two types of free cooling: direct and indirect types.
- A direct process is called when heat exchange occurs directly from the object to be cooled to the outside air.
- In the case of an indirect one, there are intermediate circuits in the system. This type is subdivided into free cooling, where adiabatic is used or not.
In the free cooling process, heat energy is transferred at no additional cost. However, for this to be possible, the temperature parameters of the surrounding space must be lower than the object being cooled. When natural heat exchange in the cooling system uses cold outside air, the process is called free cooling. The simplest of these systems is an open window.
Free cooling air cooled chiller is optimal for regions with cold climates. It can significantly reduce the period of operation of the cooling machine compressor and reduce the cost of electrical energy. This type of cooling is the most preferable due to its high energy-saving ratio.