William “Bill” I. Nelson PE, Mechanical Engineer, Emeritus, GLHN Architects & Engineers, Inc. interview for The Tucson ASHRAE Chapter on The HVAC industry in Southern Arizona from 1970 to 2020.

Bill is characterized by his exemplary contributions to the engineering profession.  His 50-year career experience spanned a multitude of infrastructure and building projects. In these videos, Bill begins by sharing working at the first architecture and engineering design firms in Southern Arizona. Bill is a long member of ASHREA and shares with Jon Ziegler, fellow ASHRAE member, how the industry has evolved in HVAC infrastructure. Upon Bill’s retirement he left us with the principle of Our Success comes from Helping Others Succeed.

This video interview sequence four segments:


Segment One: This segment talks about Bill’s early education in Tucson and his time with the United States Army in Naples Italy, up to his joining GLHN Architects & Engineers in February 1970. Time to watch 12:57 min

Segment Two: Bill covers the HVAC industry from the 70s through the 90s in the Southwest. It is during this time that early computer programs were developed for calculating the energy used within the built environment. It was also during this period that the recognition of ozone depletion by refrigerants became apparent. Time to watch 9:06 min

Segment Three: Bill reviews his time teaching in the College of Engineering at the University of Arizona, he also discusses the segmented psychrometric chart. Bill addresses the need that engineers should be leaders and consistently articulate the truth. Time to watch 15:57 min

Segment Four: This video addresses the relationship between HVAC systems and the Corona-19 virus. Time to watch 16:20 min


Also covered GLHN’s 45 year history of working with the Department of Veterans Affairs

GLHN Architects & Engineers has been practicing in the Southwest for nearly 60 years.