"We've been in the casino business for over 10 years, and in that time we've formed some opinions on how to maintain a good indoor environment," he said.
Ruecker explained that at an earlier casino facility on the site, he and his staff developed methods for controlling the indoor environment. When plans were made for a new facility, they put their knowledge to work in the creation of the Barona Valley Ranch, which is owned and operated by the Barona Band of Mission Indians.
The all-new resort facility, located on the Barona Reservation - which was established in 1932 and is located about a half-hour northeast of downtown San Diego - encompasses a large casino, luxury hotel, and a new golf course designed by the firm of Gary Roger Baird Design International.
It also has a unique mechanical system, which makes the indoor environment comfortable.
Quality Indoor EnvironmentRuecker points out that all casinos have the goal of providing a comfortable indoor environment for customers, and this is made challenging by wide variations in occupancy and the need to handle tobacco smoke.
"A significant percentage of our customers are smokers," said Ruecker. "And we believe that the best air quality solution is a high rate of ventilation, but in a way that doesn't in itself become a comfort problem."
This conclusion was drawn at a smaller Barona casino on the same site over the last decade.
"We learned that large volume ventilation with appropriately conditioned air is the best solution. So when we began planning our new facility, we insisted on a mechanical system that could meet that challenge," he said.
Construction of the new facility began in the summer of 2001. The casino was completed Dec. 11, 2002. The casino had a "soft startup" on that date, with slot machines and other equipment being brought in and started up over a two-week period.
"We wanted to be able to adjust to the new environment gradually, rather than having massive crowds on an opening night," he said.
High Summer TempsPart of the design challenge came from the location itself. The Barona Valley area has much higher summer temperatures than nearby San Diego, with annual temperatures ranging from 40 degrees to 115 degrees F. Thus, it was necessary to have a major chilled water re-source to supply the air handlers.
The chilled water source for the new resort complex is two centrifugal chillers, with a third identical machine on standby. The three machines are located in a separate mechanical plant building. The equipment selected was Trane CenTraVacâ„¢ Model CVHF electric chillers, rated at 800 tons each.
Cesar Madlangbayan, the facilities mechanical manager responsible for the day-to-day operation of the mechanical plant, indicated that the three machines are rotated on a schedule to keep the hours balanced. The plant produces chilled water at 42 degrees, with a 54 degree return. The BAC cooling towers are located at grade, adjacent to the mechanical building, and are supplied with softened well water from the facility water plant.
The cooling plant is also equipped with a plate-and-frame heat exchanger, which permits "free cooling operation" during the cooler months. In this mode, the cooling towers alone can economically supply much of the cooling needed. This method is especially effective here, where the humidity is low during the cooler months. To supply heating, the mechanical plant is equipped with three 700,000-Btu hot water boilers, which are used for heating, as well as for ventilation air reheat.
The Air-Side SystemA major design challenge for the facility was the air-side system for the casino. Ruecker points out that the casino comfort strategy requires large volumes of conditioned air. This is provided by a mixture of rooftop air handlers and indoor central station air handlers in a mezzanine space above the casino floor. The rooftop air handlers are Trane T-Series Climate Changerâ„¢ units. The T-Series unit is modular in design, and is de-signed for outdoor use. These units were specified with the exact combination of elements for each application.
The rooftop air handlers provide conditioned outdoor air that discharges through overhead diffusers into the casino gaming area. Some areas of the casinos are designated as nonsmoking areas. For these areas especially, a high ventilation rate is essential.
The indoor units are Trane Modular Climate Changerâ„¢ air handlers. The indoor modular air handlers in the mezzanine provide conditioned air for offices and other administrative spaces, as well as the large restaurant areas. These were selected with the specific combination of heating, cooling, and filtration modules to serve the 140-plus VariTraneâ„¢ VAV terminal units serving these areas.
Control SystemThe Tracer Summit building control system plays a critical role in assuring continuous good air quality.
"One of the best things we did was to go to the Summit system," said Madlangbayan. "We can precisely set conditions in different zones, and can closely monitor conditions in all of the areas."
The Tracer Summit system normally adjusts casino ventilation rates based on CO2 levels as an indicator of area occupancy, and also by measuring volatile organic compounds as an indicator of tobacco smoke levels.
Publication date: 01/19/2004