The cooling system of the split air conditioners are also based on the compression of steam, where the compressor is the element responsible for pumping the refrigerant, the condenser is responsible for its condensation, by promoting the heat exchange
between this fluid and the air from the external environment, the expansion device acts to control the amount of refrigerant entering the evaporator by causing the condensation pressure to drop to the evaporation pressure and the evaporator is responsible for the exchange of heat between the fluid refrigerant and the internal environment.
The refrigerant is sucked by the compressor through the suction line under low pressure and temperature (Example: for R22 evaporation temperature 6 ° C the pressure would be 73 psig), being compressed, thus raising the temperature (to about 90 ° C), this fluid in phase gas flows into the condenser through the discharge line which is exposed to the external medium.
If there is a temperature difference between the discharged vapor and the air from the external environment, the release of sensible heat by the refrigerant fluid occurs, ie the fluid starts to release heat, consequently its temperature will decrease until the condensation temperature is reached (about 10 to 15 ° C above the external ambient temperature). The fluid condenses by the release of latent heat of condensation, under constant temperature and pressure, and goes to the expansion device.
The expansion device, which may be located at the outlet of the condensing unit or at the evaporator unit inlet, causes a pressure drop in the liquid refrigerant liquid to enter the evaporator under low pressure and in the process of changing the liquid phase to the gas phase, that is, with the pressure drop the fluid passes from the liquid phase to the gaseous phase absorbing latent heat of vaporization under pressure and constant temperature, generally 5 ° to 7 ° C.
After the vaporization process the fluid exits the evaporator still with temperature below the external ambient temperature and follows through the suction line absorbing heat, it is said the fluid is overheating. The superheated fluid is sucked out by the compressor and starts the cycle again.
