What is an evaporator's role in an HVAC system?

An evaporator's primary role in an HVAC system is to absorb heat from the indoor air. During this process, the refrigerant within the evaporator coils evaporates as it absorbs heat from the surrounding air, effectively cooling the air that is circulated back into the living space. This phase change occurs as the refrigerant transitions from a liquid state to a vapor state, enabling the removal of heat from the environment, which is a critical function in achieving indoor comfort.

In contrast, the other options describe functions that do not pertain to the evaporator. Condensing refrigerant vapor to liquid is typically the role of the condenser, while evaporating water for cooling may relate to a different system type, such as an evaporative cooler. The distribution of cool air is handled by the air handling unit or duct system, which circulates the cooled air throughout the space. Thus, the correct identification of the evaporator's role as heat absorption highlights its essential function in the cooling process of HVAC systems.