Story by: Zoe Marcum, FS Communications Student Assistant
Here at the University of Tennessee, Knoxville, students, staff, and fans enjoy our beautiful campus year-round. But when the Tennessee weather turns sweltering, freezing, or far too humid, there’s nothing better than stepping inside and being greeted by a gush of perfectly balanced air. Every day, thousands of students rely on the heating or air conditioning of UTK buildings without knowing the science and effort behind it. The people on campus are completely unaware there is a nine-person team clocking in 50-60 hours a week to keep those systems running. That’s 10-12 hours a day making sure any Vol can focus the task at hand rather than the temperature in the building.
Rocky Top Dining was opened to the public in August of 2022 and has a new, efficient type of chill water system that uses Electronically Communicated motors (ECM) to regulate the rotations per minute (rpm) of the fans depending on the crowd inside the dining hall at any time. This allows the systems to conserve energy by lowering the rpm when less people are in the dining hall. But during lunch hour when there are as many as 1,200 Vols in Rocky Top Dining, the motors receive the signal to boost the rpm to accommodate for the extra body heat. This saves power by reducing the electricity the fans use during less busy times. This kind of high-end efficiency comes at a price. The motors that run the fans, however, cost $4,000 to replace, whereas a typical fan motor costs $800. Not to mention that UTK uses economizer systems. That means that when the outside temperature drops below 50 degrees, the building’s air conditioning unit will take air from outside and heat it up to standards to cycle through the buildings. This saves a massive amount of energy in the cooler months. Who monitors these systems and ensures they run smoothly? Facilities Services’ own AC Utilities team.
This critical team of nine people, led by David Ridings, takes care of every single cooling system on campus, all 50,000 tons of cooling equipment on campus. Most of these systems are chilled water systems, which means that a series of pipes throughout the building pump chilled water to pull heat out of the interior air. These pipes then take the now warmed water to a chiller where the heat is transferred to the cooling tower water loop. The cooling tower rejects the heat into the atmosphere and returns the water to the refrigeration unit of the building where the water is chilled, and the cycle can be repeated. These systems run all day, every day all over campus, that adds up to 53 centrifugal water-cooled chillers, 98 cooling towers, and 43 air-cooled chillers, all of which must be upkept and repaired. David and his team are on call around the clock to check on these systems, replace or repair any broken parts, and possibly replace the units. David said, “Our stuff runs 24/7, and we are responsible for it 24/7.”
One of the best ways that students, faculty, and Vol fans can help this small but mighty team is to keep exterior-leading windows and doors closed as much as possible. David admitted that a nice breeze from an open window is nice but highlighted the importance of keeping them closed as much as possible. “I mean, it sounds simple but it’s really important to our systems.” David said. The air conditioning units are designed to create positive air pressure inside the building, that is what generates that refreshing gush of air when you open a door. This pressure lets the system have full control over the airflow and heat reduction in the building and can easily be thrown off by a door propped open or a window left open. Keeping those closed as much as possible helps conserve energy and keep the buildings at their optimal temperature.
At the end of the day, the comfort we often take for granted on campus is the direct result of the dedication, skill, and long hours of UT’s AC Utilities team. Their behind-the-scenes efforts not only keep classrooms, labs, residence halls, and dining spaces running smoothly, but they also safeguard the welcoming environment that defines life on Rocky Top. Thanks to their expertise, every Vol can focus on learning, teaching, working, and cheering without worrying about what’s happening behind the vents, and that’s the kind of service that truly makes a difference.