This presentation illustrates the details of advanced High-Performance HVAC Design and is intended as the next phase of learning beyond the current “Applied Psychrometric” DL presentation by Doug Zentz. Within this presentation the following will be illustrated: understanding how DOAS systems decouple and efficiently manage the building’s latent load, how to supply very dry air near space set‑point without disturbing occupants, how stratifying space loads into the return‑air path changes space and equipment psychrometric behavior, and how to use real HVAC loads to our advantage through psychrometric processes. It also covers practical tips for correctly sizing and selecting air‑handling units, so they perform as designed for these detailed psychrometric conditions.

Douglas F. Zentz is an Emeriti Professor from the HVACR Programs in the College of Engineering Technology at Ferris State University and a past HVAC Program Coordinator. He holds a Bachelor of Science in Mechanical Engineering Technology from Purdue University (1980) and a Master of Science in Career and Technical Education from Ferris State University (2007). With over 20 years of HVAC industry experience—including roles in engineering, design–build, and custom air‑handling—he transitioned to education in 2003, where he taught senior‑level HVAC design, equipment selection, and capstone courses, and developed both on‑site and fully online curricula. Doug is deeply involved in ASHRAE, having served in multiple leadership roles, presented at over 100 ASHRAE chapter visits, taught ASHRAE Level I and II Essentials, and earned ASHRAE’s Distinguished Chapter Service and Distinguished Service Awards. He has also mentored nine student design teams recognized in ASHRAE’s Student Design Competition and has spoken at more than 100 professional events for organizations including ASHRAE, ACCA, MCA, AIA, USGBC, and RSES.