Santiago and Bryan talk about pressurization problems, especially in restaurants and janitorial closets with dry P-traps in their floor drains and imbalanced ventilation air. When buildings are under negative pressure, it can be difficult to open the door, and odors may persist.

Santiago starts his testing and balancing process by looking at the unit. He then starts putting together a test plan and accounting for dampers. He measures system airflow and ventilation airflow by measuring the fresh air intake, and he also does duct traverses with pitot tubes. He takes the average velocity and multiplies it by the area to get the airflow. You must put together a good report in order to balance the airflow properly; otherwise, you risk causing problems like pressurization issues or an inability for the coil to remove as much heat as possible.