The S-Class™ rooftop product line includes 50-ton models featuring R-410A refrigerant and factory-installed electric heat as an option. Efficiencies up to 9.5 EER and 11.2 IPLV are available. The electric heat factory option is available of 35- to 50-ton models and can provide up to four stages of operation.
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.