In a forced-air system, static pressure is a force that ____________.

Static pressure in a forced-air system refers to the pressure exerted by the air within the ductwork. This pressure pushes against the walls of the duct from the inside, ensuring that air is distributed throughout the system effectively. It is an important factor in maintaining the proper airflow and ensuring that air reaches the intended areas without significant leaks or losses.

Proper static pressure levels are essential for system efficiency. Too high or too low static pressure can lead to imbalances in airflow, affecting the overall heating and cooling performance. Thus, understanding that static pressure is the force that pushes against the duct walls is crucial for anyone working with forced-air systems, as it directly relates to the system's ability to operate optimally.