What do the service site conditions suggest if a house feels "drafty" in cooling with a properly sized ductwork and high supply face velocities?

In this scenario, feeling "drafty" indicates that there is a significant sensation of moving air, which often occurs when air velocity from the supply registers is high. If the ductwork is correctly sized and the volatility is high, it suggests that the air being delivered is at a speed that can create discomfort rather than achieve efficient cooling.

When supply registers are too restrictive, they can impede airflow, causing the air to be pushed out at greater velocities. This can lead to draftiness even when the system is functioning properly in terms of cooling capacity. The discomfort experienced from drafts is not necessarily a sign of inadequate system performance but rather the result of the air being forced out of the registers more forcefully than desired due to restrictions in the duct system. By addressing the restrictiveness of the registers, the airflow can be moderated, enhancing comfort levels in the space.

Other conditions like the system needing replacement or underperforming could be considered if other metrics suggest inefficiency. However, given the context of high supply face velocities and correctly sized ductwork, it's clear the sensation of draftiness comes from the engine being forced out too aggressively rather than other issues.