Headway in hospitality

Engineered Systems, Feb, 2005 by Barry Campbell

Hosting 40 million visitors each year, Central Florida's economy relies on eating and entertaining like few others. From high humidity to saltwater spray, and a food prep lab with multiple ventilation hoods, all sorts of challenges face HVAC designers striving for comfort in the Orlando area. Visit a hospitality management college, a fast food restaurant, and a Daytona Beach theme restaurant to see solutions to their quandaries.

The University of Central Florida's Rosen College of Hospitality Management is located in what might be the largest learning laboratory in the world for hospitality and tourism--Orlando. The satellite campus was designed as a city within a city and boasts some impressive amenities, but the HVAC design work that went into it is also worth a look.

Orlando is truly a vacation Mecca. The city's International Drive is at the epicenter of the vacationing mayhem, with a truly vast selection of hotels, restaurants, shopping venues, and plenty of tourist attractions. So when local hotelier Harris Rosen donated $18 million for the construction of a state-of-the-art hospitality college, International Drive was an ideal location. It also helped that Rosen (who owns over 15,000 hotel rooms on the strip) donated the 30-acre site for the project, which was actually to serve as a satellite campus of the University of Central Florida (UCF)--and that his financial donation was matched by the State of Florida.

This 150,000-sq-ft school is about 15 miles from the UCF campus and was designed and constructed to support the department's goal of becoming the world's premier hospitality management school. The idea of locating the school apart from the campus and next to world famous theme parks and venues was that it would foster relationships between the school and hospitality industry leaders.

The school was designed by prominent Orlando architect, Helman Hurley Charvat Peacock/Architects, Inc., which brought Orlando-based GRG Consulting Engineers, Inc. on to serve as the design engineering firm. Since the program teaches students how to manage all aspects of venues ranging from restaurants and bars to hotels and theme parks, its facility presents inherent HVAC design challenges.

CITY WITHIN A CITY

The facility has its own library, bookstore, theater, and dorms (which are currently under construction). Two large classrooms are wired to facilitate "distance learning" sessions anywhere in the world. Several specialty spaces, not typically found at other academic institutions, required extraordinary HVAC design consideration.

For example, one of the three kitchens (called food labs) in this building has 16 grease hoods. "These teaching stations are intended to operate independently from each other as dictated by class size. Since about 25% of the makeup air to each hood is preconditioned at the AHU, the variable number of hoods in use at one time created a building pressurization challenge," explained Walter V. Brennan, Jr., P.E., and project manager, with GRG.

If all hoods were to be operating at the same time and there wasn't enough outside air introduced at the AHU, then the kitchen would become excessively negative, if only half the hoods were operating and there was too much outside air being introduced at the AHU, then the kitchen would become excessively positive. "To address this problem, a variable outdoor air damper was utilized. Its position is modulated based on the static pressure differential between the kitchen and the adjacent space," Brennan explained. "In this manner, if the kitchen becomes too negative due to all the hoods being on, more outdoor air is introduced to the space to maintain the slight negative pressure with the adjacent training dining room," Brennan added.

VINTAGE PROBLEMSOLVING

Another HVAC challenge facing the GRG team was the wine/sensory lab. A unique feature of this space is its walk-in wine storage room. Depending on the products being stored, the temperature and humidity in this space needs to vary from 68[degrees] to 78[degrees]F and 40% to 100% rh. To provide this environment, a dedicated fancoil unit was selected to control the temperature while a wall-mounted space humidifier was furnished to modulate the humidity.

To serve the cooling needs of these different types of spaces, two HVAC systems were considered--individual DX packaged units vs. a central chilled water plant. While the DX option offered a lower first cost, the chilled water system was ultimately selected for other reasons including acoustical concerns, high percentages of outdoor air, and lower maintenance costs, Brennan said.

Still, costs were a challenge. While there was solid funding for the project, its focus leaned more toward first-cost savings as opposed to operating cost minimization. University management also sought an integrated HVAC system/control vendor. As a result, air cooled chillers with a variable primary pumping arrangement were selected. After a bidding process, GRG specified two 500-ton Trane RTAC air chillers and 12 rooftop T-Series units, along with 99 VAV single duct terminal units and six fan-powered terminal units.