HVAC 101: A (brief) overview of how your HVAC system works

Basically, your fan coil unit uses conditioned water to heat and cool your suite’s air. That water is supplied through large pipes (referred to the in industry as “risers,”) which run the height of your building. These pipes branch off into each unit, and feed water into your fan coil unit.

When entering your suite, the water first passes through an isolation valve (which can shut the water off, if necessary), and then passes through the actuator valve assembly (which controls the flow.)  Finally, it moves through the coil, which heats or cools the air (depending on the season and subsequent settings.) The water then returns to the building system through the return isolation valve and riser.

All these components and their connection points are susceptible to failure - meaning, if they’re not properly maintained, they can cause leaks, water damage and/or mold growth. That said, the most common cause of leaks isn’t actually from this system, but rather from what’s known as the condensate drain pan. This is a pan with a drain, located under the water coil, which serves to collect condensation during the cooling season.