Lochinvar Heats Water to the Stratosphere
by Lochinvar | 06/20/2008
It takes an extraordinary image to command attention in Las Vegas, the "City of Lights." But wouldn't you notice a 1,149-ft. high needle-like structure, which boasts a 12-story rotating "pod," a gazillion lights, and the world's highest roller coaster?
The structure is Stratosphere Tower, a $500 million hotel, casino and entertainment complex. The tower opened on April 29, 1997, but not without a few hitches. Having to supply hot water and hydronic heat for the hundreds of people who would be dining and site-seeing in the structure was certainly a challenge. And imagine having less than a 3 feet deep by 15 feet wide hollow core to work within. It sounds like an HVAC tall tale. But this was the task that faced the engineering and mechanical teams that were responsible for Stratosphere Tower's HVAC systems. Stratosphere Tower is home to the tallest free-standing observation tower in the United States. Atop the 135 story tower, the High Roller, the world's highest roller coaster, slings thrill seekers around an 865 foot track. And the Big Shot, already sitting at the 921-foot level, propels riders another 160 feet straight up the mast of the tower with the force of four G's. Dizzy yet? With Stratosphere Tower's unique shape, space was scarce, especially in the 12-story pod, which already housed a revolving restaurant, two observation decks, a 220-seat lounge, offices, retail space, three wedding chapels and two "safe area" floors for use in an emergency.
At first, Kris Kalkowski, a design engineer of Dunham Engineering, planned to install boilers and a commercial water heater in the central plant on the ground floor and pump up the hot water supply. Upon further review of the situation though, he realized he'd need a more innovative approach. Instead of piping the hot water up to the pod, he decided to provide hot water heating at the top of the tower.
"The decision was based on cost and space limitations," Kalkowski said. "There was simply not enough space in the inner sphere for the required supply and return piping."
The sphere was already occupied by the drainage, chilled water, and domestic water systems. But how would they fit the necessary water heater and boilers into the limited space of the pod? Fortunately, Kalkowski received a break when a pod floor originally designated as office space was deemed too small and was made available for mechanical and electrical use. The small room became the pod's mechanical room where the hot water equipment could be stored. Kalkowski looked into a number of possible boilers and water heaters, but kept hitting a snag because of the Nevada State Boiler Code. The code states that boilers must have a minimum of three feet of clearance for maintenance. The mechanical room's sloping walls made this a tough call. Fortunately, Kalkowski found a solution by specifying three Lochinvar Power-Fin boilers and a Lochinvar Power-Fin water heater. The units met the design criteria for size, output, and venting.
"The size of the boilers made the Lochinvar units the logical choice for our limited space," said Kalkowski. "The small footprint of the Model PBN1000 greatly aided our ability to fit four units in an extremely cramped space and still meet code."
The venting capabilities of the boilers were also a perfect fit for the system.
"The combination direct vent and intake worked well with the sloping exterior metal panels and provided minimal penetration," said Kalkowski. " Conventional combustion air vent openings were not a workable option."
The boilers were able to meet system demand by supplying the 3,000,000 BTUs of heat necessary for the restaurant, lounge, and office space. And the water heater (Model PFN1000), with the capacity to supply in excess of 1000 gallons of hot water per hour, was easily able to meet the systems' hot water demands.
One of the most crucial aspects of the process was the delivery of the four Lochinvar units. The units had to be lifted by crane 800 feet to the pod's mechanical room. The wind, height and small working area all played havoc with the Hansen crew. Fortunately, the installation went smoothly and the mechanical systems' schedule stayed on track. Other than a few minor repairs, the mechanical systems' startup test went without a hitch. Everything was ready for Stratosphere Tower's grand opening.
"Our involvement with Stratosphere Tower was exciting, since it was such a high profile project, even for Las Vegas," said Sy Brown, the local Lochinvar rep. "When you need the right product at the right time, you can't gamble with your options."