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.
Symphony Limited
Symphony Limited was founded in the year 1988 by Achal Bakeri. Then later in the year 1990, Symphony aired its first TV campaign. Symphony went public in the year 1994 and was also listed at Bombay, Ahmedabad and Delhi stock exchanges. It also included water heaters in its range of products in the same year. In the year 2000, Symphony introduced the world's largest air cooler, Sumo, which got the Guinness World Record certification. It launched mid-segment coolers, in the year 2001. For coastal markets, in the year 2004, Symphony launched the H! Cool air cooler. Symphony's winter air cooler and Sauna water heater were introduced in the year 2005. In 2006, Symphony expanded itself into 33 other countries and also introduced the Surround cooler. In 2008, it separated the range of air coolers in two different ranges. Also launched Jumbo Jr., H! Cool with Ionizer in the same year. In 2009, it launched Sauna water heater, India's first water heater with a 5-star power savings rating. It also acquired IMPCO, USA, in the same year. In 2010, Symphony introduced Industrial coolers in Indian market. Symphony introduced air coolers with remote control, in the year 2011. In 2012, Symphony launched digital models named Storm 70E and Storm 100E.