Demolition, construction, changing ΔT, two chiller plants, changing piping designs, adjusting makeup water pressure, incorporating thermal storage ... these are but some of the hurdles and goals the project team has faced during a major retrofit at the Centers for Disease Control in Atlanta. In short, site limitations and economics pointed to connecting the chiller plants and investing in thermal storage, but that just scratches the surface of this critical work. If you think your chiller retrofit is involved, read this and feel better.
Leaning on experience and data from various K-12 cities and projects, the author pursues some less conventional design approaches. They may revolve around radiant heating and/or cooling, but depending on school size and other factors, the smart use of heat recovery, DOAS, and improved central plants could also put a project on the HVAC honor roll.