What component is responsible for circulating air in a ducted HVAC system?

In a ducted HVAC system, the air handler plays a critical role in circulating air throughout the home or building. It is responsible for moving air through the ductwork, distributing heated or cooled air to various areas. The air handler typically contains a blower fan, filters, and other components that contribute to this airflow process.

The importance of the air handler lies in its ability to maintain comfortable indoor temperatures by ensuring that conditioned air reaches all spaces uniformly. Proper functioning of the air handler is essential for the system's overall efficiency and effectiveness in maintaining air quality and comfort levels.

The other components listed, like the compressor, expansion valve, and reversing valve, serve different functions within the HVAC system. The compressor is responsible for compressing refrigerant and creating the high-pressure side of the system. The expansion valve controls the flow of refrigerant into the evaporator. The reversing valve is specifically used in heat pump systems to change the direction of refrigerant flow for heating or cooling. Each of these components contributes to the overall functionality of the HVAC system, but they do not directly circulate air through the ductwork, which is the primary role of the air handler.