At Rio Grande Regional, 17 air-handling units (AHUs) are nine years old and range from 20 tons to 80 tons. Nine AHUs are four years old and are 70 tons to 80 tons. After reviewing the potential benefits of UVC, Molano approached the hospital’s CEO and received approval to retrofit the 26 AHUs with UVC on a phased basis.
“As our UVC retrofit program has progressed, we have seen a continuing and dramatic improvement in energy performance,” said Molano.
Here is what Molano and the hospital discovered:
• Before any UVC devices were installed, the four 465-ton chillers serving the hospital were running at 99 percent capacity. According to Molano, chilled water “in” measured at 43°,while chilled water “out” measured at 64°.
• About 18 months later, after most of the AHUs had been equipped with UVC, the same chillers were running at only 62 percent capacity. According to Molano, chilled water “in”remained at 43°, but chilled water “out” temperature had decreased to 53°, an 11° degree drop.