Air Conditioning Repair Certification (ETI) Practice Exam

The process primarily responsible for cooling the air in an air conditioning system is heat exchange. In an air conditioning system, the refrigerant absorbs heat from the indoor air during the cooling cycle. This heat exchange occurs within the evaporator coil, where the refrigerant evaporates, absorbing heat in the process. As the air passes over the coil, it is cooled down and circulated back into the living space. The transfer of heat from the indoor air to the refrigerant is key to creating the cool environment we expect from air conditioning units.

While evaporation does play a crucial role in the process by allowing the refrigerant to change states from liquid to gas, the term "heat exchange" encompasses the entire interaction of the refrigerant and air, highlighting the cooling effect that results from this process. Other processes like condensation involve releasing heat when the refrigerant changes states back to liquid, and radiation is not a significant factor in the cooling process of air conditioning.