ESCO Air Conditioning Practice Exam

Thermal expansion in the context of air conditioning specifically refers to the process wherein refrigerant expands and cools, allowing it to absorb heat from the indoor environment. When the refrigerant reaches the evaporator coils, it undergoes a phase change from liquid to gas. This expansion is crucial because it enables the refrigerant to absorb heat from the air inside the space being cooled, effectively lowering the indoor temperature.

During this process, as the refrigerant absorbs heat, its temperature drops, which is a fundamental principle of how air conditioning systems provide cooling. This mechanism allows the refrigerant to efficiently transfer heat, which is essential for the overall effectiveness of the air conditioning system. The other choices do not accurately describe the primary function and behavior of refrigerant during this cooling process, focusing instead on different aspects of the refrigerant cycle.