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.
St George's Hall, Liverpool
In the basement is part of a unique heating and ventilation system devised by Dr Boswell Reid. This was the first attempt at providing air conditioning in a public building in the United Kingdom, its aim being to warm and ventilate the building without draughts. Air was warmed by five hot water pipes which were heated by two coke-fired boilers and two steam boilers. The air was circulated by four fans wide. It was controlled by a large number of workers opening and closing a series of canvas flaps. In 2005 the Heritage Group of the Chartered Institution of Building Services Engineers awarded its first Blue Plaque to St George's Hall recognising it as the World's First Air Conditioned Building.