What Is An Automotive Air Conditioning Evaporator?

Automotive air conditioning evaporator is the core component of the air conditioning system to achieve refrigeration, cooling, its role is to absorb heat through the evaporation of refrigerant, the air inside the car cooled down, but also remove some of the moisture in the air, equivalent to the indoor unit of the household air conditioning.

Principle: the evaporator inside the flow of low-temperature, low-pressure liquid refrigerant (such as R134a), when the high-temperature air flows through the evaporator surface, the liquid refrigerant absorbs heat in the air and rapidly evaporates into a gaseous state, thereby reducing the temperature of the air to achieve the effect of refrigeration.

Analogical understanding: similar to “ice cubes in a cup, the outside of the cup will become cooler”, the evaporator is through the refrigerant “sucking away” the heat of the air, so that the air becomes cold.

Workflow in the air conditioning system

Refrigerant cycle path:

from the expansion valve out of the liquid refrigerant (about - 5 ℃ ~ 0 ℃) into the evaporator, absorbing the heat of the air evaporated into a gaseous state;

gaseous refrigerant is sucked by the compressor, compressed and warmed up into the condenser to dissipate the heat, and then into the liquid state, to complete the cycle.

Air treatment process:

The air inside the car is blown to the evaporator by the blower, and is cooled when it flows through the low-temperature fins;

The cooled air is sent into the car through the air ducts, and the condensed moisture is discharged out of the car by the water catching tray at the bottom of the evaporator.