Nate Core Practice Test

The use of registers and grills is essential for controlling airflow within ducts in HVAC systems. Registers are typically equipped with adjustable louvers or dampers that allow users to control the volume of air entering a room. By opening or closing these louvers, one can effectively direct airflow to ensure proper heating or cooling throughout the space. Grills, on the other hand, are often used for return air, allowing for the efficient circulation of air back into the HVAC system.

This method of airflow control is critical for maintaining indoor comfort and energy efficiency. Registers and grills can significantly impact the distribution of conditioned air, ensuring that every area of a building receives the appropriate amount of heating or cooling. Other options do play roles in HVAC systems but do not specifically relate to the direct control of airflow within ducts. Thus, registers and grills stand out as the primary components for this function.