The DX coil is a very important part of the four major pieces of AHU. The evaporator is a heat exchanger
The high-pressure liquid refrigerant enters the evaporator through the expansion valve. Due to the atomization of the expansion valve, the liquid refrigerant becomes a mist, and the mist-like refrigerant changes to a gaseous state under low pressure conditions.
During the transformation, heat is absorbed, so the evaporator is cold at this time. After the wind passes, it turns into cool wind, achieving the purpose of cooling.