From sidewalks to hospital entrances and helipads, these systems are becoming a more common part of a project’s mechanical infrastructure. Examine differences between ASHRAE’s old and updated classifications, then review design considerations such as heat of evaporation, heat loss to the atmosphere, and back and edge losses. Tubing, spacing strategies, and controls round out the primer.
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.