Dedicated Outdoor Air, Energy Recovery Rise to School's Ventilation Challenge System prevents recurrence of serious mold issues

摘要

One might not expect mold problems in the arid Arizona climate, but from mid-July through September, the city of Yuma experiences "monsoon season." Over the years, serious mold issues developed in both buildings on the Yuma High School campus: Old Main, a three-story, 30,000-sq-ft facility built in 1910, and Snider Hall, a two-story, 20,000-sq-ft facility built in 1921. Two-pipe fan-coil units installed in each classroom were not sized to handle increased humidity. Additionally, the buildings were designed to provide only 5 cfm of outdoor air per person, even less of which was delivered because outdoor-air dampers often were closed. The lack of ventilation resulted in carbon-dioxide (CO_2) levels of 2,000 to 6,000 ppm.