In a given cooling scenario, what does a house feeling "drafty" with properly sized ductwork and high supply face velocities indicate?

When a house feels "drafty" despite having properly sized ductwork and high supply face velocities, it suggests that while the airflow is sufficient, there is an issue with how that air is being delivered into the living spaces. High face velocities typically mean that air is being forced out of the supply registers quickly, which can lead to a perception of drafts.

The correct scenario indicates that the supply registers are too restrictive. When the registers are not allowing sufficient air to flow freely or are designed in a way that creates turbulence or noise, occupants may experience uncomfortable drafts. This can result in a situation where even though the ductwork is appropriately sized and the system is operational, the quality of airflow through the registers affects comfort levels in the home.

This highlights the importance of not just sizing components correctly but also ensuring they are well-designed and unobstructed to allow for smooth airflow. In contrast, undersized returns would typically result in insufficient airflow or pressure in the system rather than feeling drafty, and setting the blower at a high CFM could unintentionally cause noise without necessarily leading to a drafty feeling.