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.
Samuel Cleland Davidson
Sir Samuel Cleland Davidson, KBE (18 November 1846 – 18 August 1921) was an Irish inventor and engineer. Through his career in the tea import business he invented and patented a number of industrial machines and developed the earliest air conditioning systems. He founded the Sirocco Works in Belfast in 1881.