Which device enhances the performance of an HVAC system by controlling air flow?

The air handler is integral to an HVAC system because it is responsible for circulating and controlling the flow of air throughout the system. It typically consists of a fan or blower, which helps distribute conditioned air to different areas of a building, and may also include filters, heating or cooling elements, and dampers. By effectively managing the airflow, the air handler enhances the overall performance and efficiency of the HVAC system, ensuring that air reaches desired areas while maintaining appropriate temperature and humidity levels.

In contrast, a thermostat primarily manages temperature by switching the heating or cooling system on or off based on the desired set point. This device does not directly control airflow. A humidistat monitors and controls humidity levels, playing a different role in maintaining comfort but not specifically focused on airflow. The compressor is essential for the refrigeration cycle in air conditioning systems, compressing refrigerant, but it also does not regulate airflow directly. Thus, the air handler's role as a mechanism that actively manages and enhances airflow solidifies its importance in optimizing HVAC system performance.