David Nelson Crosthwait Jr.
(May 27, 1898 – February 25, 1976)
Engineer, Journalist, and Inventor
Inventor of the heating system for Rockefeller Center and New York’s Radio City Music Hall.
From the 1920’s to 1940’s. He invented a new thermostat control, an improved boiler, a new differential vacuum pump and more effective heating sustems for larger buildings.
He was an exceptional mind and a master of HVAC technology. Starting out as a researcher tech. & Director at C.A. Dunham Company, he excelled in his studies and lab work. Mr. Crosthwait did not Invent the HVAC system in general, only his specific way of implementing it which garnered many of his Patents. Nonetheless, he was a very accomplished man with several Degrees in Engineering.
He was an African-American mechanical and electrical engineer, inventor, and writer. He was born in the city of Nashville, Tennessee. He grew up in Kansas City, Missouri. Once he completed high school. attend Purdue University where he obtained a Bachelor of Science degree in 1913 and a Master of Engineering degree in 1920.. He was granted an honorary doctoral degree in 1975.
Crosthwait’s expertise was on air ventilation, central air conditioning, and heat transfer systems. With this knowledge and passion, he created many different heating systems, refrigeration methods, temperature-regulating devices, and vacuum pumps. He holds 39 United States patents, as well as 80 international patents. In the 1920s and 1930s, Crosthwait invented a vacuum pump, a boiler, and a thermostat control, all for more effective heating systems for larger buildings. Some of his greatest accomplishments were for creating the heating systems for the Rockefeller Center and New York’s Radio City Music Hall.
He later wrote and revised an instruction manual and guides for heating and cooling with water and guides, standards, and codes that dealt with heating, air conditioning, and ventilation systems.
After retiring from the field in 1971, Crosthwait began to teach a course on steam heating theory and control systems at Purdue University. He was awarded an honorary doctorate from Purdue University in 1975, Crosthwait belonged to a number of national organizations including the American Society of Heating and the American Chemical Society.
He was granted an honorary doctoral degree in 1975 from Purdue University. In 1971, Crosthwait was elected as a fellow of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), making him the first African American fellow. Crosthwait was also named a fellow of the American Association for the Advancement of Science (AAAS).
He Invented many advancements in the HVAC field at he won awards from the National Technological Association in the 1930s. He stayed on as a Technical advisor for Radio City Music Hall for almost 40 years before retiring in 1969. He would write many articles and Testimonies regarding his mastery of HVAC. He is the owner of over 30 U.S Patents and a collection of 119 total Patents worldwide. He ended his Professional Career as a Professor at Purdue University in Indiana.
He died on February 25, 1976, in West Lafayette, Indiana. and died one year later in 1976.