Evaporator
The evaporator is a heat exchanger mounted in the climate unit inside the car.
As the refrigerant enters the evaporator, it expands and becomes gaseous (boils). Due to the suction of the compressor, the pressure in the evaporator is much lower than in the rest of the circuit.
As the refrigerant boils, it absorbs heat from the surrounding air, which thereby becomes colder. This air is blown into the passenger compartment by the blower.
The gas leaving the evaporator is at low pressure (1.5 - 3 bar/21.7 - 43.5 psi) and low temperature (approx. 2 - 5 °C/35.6 - 41 °F). The gas passes to the air receiver (dryer).