Before modern day air conditioning people still needed to be kept cool and some ingenious inventions applied the principles of cooling centuries ago. The ancient Romans used water from aqueducts to circulate through house walls to cool them down. In Persia buildings were cooled using a cistern device and wind tower system combination the hot season.

In China during the 2nd century, a Chinese inventor Ding Huan invented a manually operated fan with seven wheels three meters diameter and there is mention of a ‘Cool Hall’ in the Imperial Palace during the Tang dynasty that used water powered fan wheels for air conditioning and jet streams of water from fountains. The fans whether water or manually powered are mentioned as being in common use right through the later Song dynasty.

Various attempts at designing a device for cooling began long before any satisfactory designs were introduced to the market. One of the first attempts in more recent times was by an American doctor to treat fever patients. In 1840 or thereabouts, Dr John Gorrie created a device that used compressor technology to blow air over ice to cool hospital rooms in Florida. He had a vision that machines of this type would be used to cool entire buildings and even entire cities could be cooled by centralised air conditioning. He did receive a patent for his device but sadly when is financial backer died so did his dreams and he died impoverished. It was another fifty years before air conditioning was thought of again.

Willis Carrier an American engineer manufactured a near relation of the modern air conditioning units in 1902. The device was designed to lower humidity and cool air. It worked successfully and soon caught on in industry to cool machinery and was used in a few medical institutions. The very first domestic use was in the home of a millionaire’s son in Minneapolis. However, these devices were expensive, too big, and toxic due to the ammonia coolant.

In 1922, Carrier made significant changes, replaced ammonia with a safe coolant dielene, and added a central compressor to reduce the size of the unit. From this time, air conditioning units began to appear in theatres, cinemas and finally offices, department stores and railway carriages. The United States government began to install air conditioning in The White House, Senate, and Supreme Court in 1928. After World War II, window air conditioning devices in America became popular and reached over one million sales in the early 1950’s.

Advanced engineering and invention in air-conditioning continues, with an emphasis on energy efficiency and on improving air quality. Climate change issues are being addressed because along with the normal greenhouse gases released with energy use, CFC, HCFC, and HFC refrigeration gases are potent when leaked to the atmosphere. Because of the significant impact these gases have on global warming, alternatives are being sought and research and development continues in this area.

Today, to be without air conditioning in hot summer conditions is unthinkable. Cars, offices, shops, and public buildings are cooled for our comfort and increasingly in northern Europe, domestic air conditioning units are seen as an option that most homes need during the summer. With the weather of recent years being unpredictable, often heat waves strike without warning. In these intense conditions, thoughts turn to a permanent cooling solution for the home.