David Nelson Crosthwaite Jr. studied mechanical engineering at Purdue University before taking a job with the C.A. Dunham Company (now Dunham-Bush, Inc.). At Dunham, Crosthwait conducted innovative research and designed the heating system for Rockefeller Center and Radio City Music Hall. He held 119 patents—39 in the U.S. and 80 internationally—all in relation to heating, cooling, and temperature regulating technology.

Besides research, product development and HVAC system design, Crosthwait also advanced his field by writing articles and revising sections of several editions of American Society of Heating and Ventilation Engineers Guide. Crosthwait's accomplishments were recognized by many in his field: He won a medal from the National Technological Association in the 1930s and was made a fellow of the American Society of Heating, Refrigeration and Air Conditioning Engineers in 1971—making him the first African American to receive the honor.

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