When the refrigerant is admitted to the condenser, it is in the same state as the compressor discharge, that is, hot gas at high pressure. As in a refrigeration system the objective is to evaporate the refrigerant (to cool and remove heat from an environment and / or product), the refrigerant in the gaseous state must be condensed before returning to the evaporator.
The condensation process of the refrigerant fluid takes place along a heat exchanger, called a condenser, in three distinct phases which are:
1. Desuperheat: The gas, when discharged from the compressor, is at a high temperature. The initial process, then, consists of lowering this temperature, removing sensitive heat from the
refrigerant, still in the gaseous state, until it reaches the condensing temperature.
2. Condensation: When the gas reaches the temperature of condensation, it begins a process of change of state. In this process, latent heat is removed from the refrigerant, i.e., the its temperature remains constant throughout the process.
3. Sub-Cooling: After condensation, the refrigerant, now in a liquid state (saturated liquid), is cooled by a few more degrees, using an intermediate heat exchanger.