Tang dynasty
The inventor Ding Huan (fl. 180 AD) of the Han dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (10 ft) in diameter and manually powered. In 747, Emperor Xuanzong had a "Cool Hall" built in the imperial palace, which the "Tang Yulin" () describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song dynasty, written sources mentioned the air conditioning rotary fan as even more widely used.
Seichi Konzo
Seichi "Bud" Konzo (1905 – 1992) was a professor of engineering at the University of Illinois at Urbana-Champaign from 1929-71 and a pioneer in the field of home heating and cooling. He lived in the first air-conditioned house in North America in 1933. His research spanned the decades of the 1920s to the 1990s.