Air-Cooled HVAC Retrofit: Safe Bet for Vegas Schools PDF

VAC maintenance costs for the retrofitted Garrett Middle School in Las Vegas were less than half of the costs to maintain two similar schools’ existing systems. The difference is attributed to Garrett’s replacement of RTU multizone units with an air-cooled chiller, closed loop chilled water system and multizone airhandling units (AHUs). Designers performed a life-cycle cost analysis to find out how well this retrofit system could be adapted for two other Las Vegas schools. This article describes the retrofit system and the analysis used to incorporate the best features of the Garrett system into the other schools.