SYSTEMS INSTALLED
1 600-ton CenTraVac;
1 S-Series design CenTraVac
ONE MILLION SQUARE FOOT HOSPITAL KEEPS COSTS DOWN WHILE STAYING TECHNOLOGICALLY AHEAD.
The facilities staff at Carilion Roanoke Memorial Hospital faces all the challenges confronting modern hospitals: rising energy costs, changing space allocations, and of course, pressure to hold down operating expenses while still increasing building comfort and IAQ. Considering CRMH is a one million square foot facility, utility costs can eat up a significant portion of the operating budget. Yet, even with costs as a priority, they are not the only driving force behind the staff’s decision-making process — especially when it comes to HVAC. “We want to be on the leading edge of technology. That applies to our medical technology and it also applies to our comfort systems,” said Johnny Morris, the hospital’s director of engineering and maintenance. Since the 15-story hospital is constantly growing, including recent additions of a South Pavilion and a 146,000 square foot Mountain Pavilion, they are also constantly focusing their efforts on improving their chiller plant operation and performance. “Over 80 percent of our facility operation expense is utilities, and a major part of that is the comfort system, so we look at the chiller plant very closely,” said Morris. But they don’t do it by themselves.
When CRMH launched a major chiller plant improvement to create more capacity for building expansion, they called on Trane. As Morris explained, this isn’t something new at CRMH, “We’re modifying our system all the time, and we need Trane’s expertise.... Our partnership with Trane has been broad and deep.” After an extensive review of the chiller plant, one chiller was retired, leaving three in operation. These chillers were a 450-ton 1969 Trane CenTraVac™ unit, a 900-ton model CVHE installed in 1982, and a 1200-ton 1993 TRANE CenTraVac model CVHF. Although they were still operating well, it was determined that two more chillers would be necessary. Considering how well the older CenTraVacs had operated, it was not surprising that one of the new chillers chosen was a high-efficiency 600-ton TRANE CenTraVac. The second chiller, however, was a choice that underscored CRMH’s commitment to new technology. Working in partnership with Trane, they decided to field-test a new S-Series design CenTraVac. This chiller still produced CenTraVac’s trademark combination of high efficiency and outstanding performance, but it also had another interesting feature. Its innovative design featured an oil-free compressor that promised to sustain optimal efficiency over the entire lifetime of the chiller. It was an exciting opportunity for CRMH to upgrade their chiller plant with cutting-edge technology, and it provided Trane with a real world comparison of the tried-and-true CenTraVac technology and the new S-Series.
Adding new chillers increased capacity, but Trane looked at opportunities to increase efficiency as well. By re-piping the existing chillers to allow a common header, and adding the new chillers to that system, CRMH would not only receive increased capacity, but they would received much greater control over efficiency. Bill Upthegove from Trane Virginia said this step was logical because it allowed Morris’ staff to select chiller operating priorities based on chiller characteristics, not piping limitations. Moreover, says Upthegrove, “they get added security by making every chiller available.” Chiller efficiency was further increased by expanding the functionality of CRMH’s Tracer Summit System. Trane also fitted the pumps and fans with variable speed drives to allow the Summit system to optimize operation of these units as well, providing further energy savings. The results of these improvements were noticed quickly. Terminal units began receiving lower-temperature chilled water, providing more cooling capacity and improved dehumidification. Trane also replaced radiant cooling ceiling panels with VAV boxes or fan coils in many of the patient rooms, solving an old hospital problem of “slow cooling response and condensation problems,” according to Morris. The relationship between Trane and Carilion Roanoke is an example of how Trane views its customers — as partners in a never-ending quest for better HVAC systems.
QUOTE:
“We want to be on the leading edge of technology. That applies to our medical technology and it also applies to our comfort systems,” said Johnny Morris, director of engineering and maintenance at CRMH