How Does Air Conditioning Work?

Since its invention in the early years of the 20th century, air conditioning has provided a silent revolution that deserves wider recognition. Imagine the great state of Florida for example, in particular the city of Orlando. Were it not for the advent of affordable air conditioning (and a certain Mr Disney’s involvement) the state would have remained destitute due to its swampy, acrid atmosphere, which is hardly conducive to comfortable living.

In offices, homes, shops and places of worship throughout the developed world, air conditioning is counted upon to supply temperate atmospheres in climates that might otherwise be frankly unliveable. Here we’ll take you through a brief history of air conditioning and then go on to explain the basics of how it works any why it’s one of the most important technological inventions of the past 200 years.

air conditioning unit

Air conditioning unit’s job is effectively to take heat from inside
a building and transfer it outside, cooling the building and its
inhabitants in the process by reducing ambient air pressure.

The History

The very first ‘modern’ air conditioning unit (i.e one which used electronics instead of mechanical, moving parts) was built in 1902 by and engineer from Brooklyn, New York called Willis Haviland Carrier. Prior to this invention a far more prosaic form of ‘mechanical’ air conditioning had been in use that worked by compressing and liquefying ammonia to create an icy evaporation that effectively chilled the air. These systems were incredibly unstable though and impossible to mass produce so we’ll refer to these simply as progenitors of modern air conditioning. Carrier designed the system for the Sackett-Wilhelm’s Lithography and Publishing Company, who were having trouble at their plants with the paper absorbing moisture from the warm air. This made applying ink to the paper almost impossible.

Carrier’s idea was to devise a system that blew across cold coils, effectively cooling the air as it passed through the pipes and into the plant. This not only solved the humidity problem in the plant but had a pleasing side effect, namely that its cooled the temperature in the plant in general. The workers were ecstatic and Carrier realised he’d inadvertently created one of the most important industrial appliances of the 20th century. Within months similar systems were installed in theatres, stores and warehouses across New York and beyond.

What is air conditioning?

An air conditioning system is defined as a system which does the following:-

  • Sustains a suitable and comfortable humidity throughout a building.
  • Free the atmosphere inside a building from excessive, potentially damaging humidity.
  • Supplies ventilation.
  • Removes harmful micro-organisms such as dust, dirt and bacteria from the air.
  • Cools a building in summer and helps heat a building in winter.

Its job is effectively to take heat from inside a building and transfer it outside, cooling the building and its inhabitants in the process by reducing ambient air pressure. In theory an air conditioner has a great deal in common with a refrigerator, only air conditioners are not closed off to insulate internally, instead the job is up to the walls of the building to keep the colder air in and the warm air out.

How does it work?

In theory, even the most technical modern air conditioning units don’t work in a significantly different manner to Carriers prototype, at least they work on the same basic principles. Air is cooled by being blown over a set of chilled refrigerated pipes known as an ‘evaporator coil’, a simple process that’s based on some incredibly clever science. The evaporator coil takes advantage of a process called ‘phase conversion’, which absorbs heat when a liquid is converted into a gas. Inside the coil, chemical compounds are forcing this reaction to happen over and over again, thereby keeping the coil cool, the same principal applies to the coils in a typical refrigerator. When the hot air moves over the cold coils, the compound inside them absorbs the heat from the air and the cooled air is passed into the building. In principal it’s no different from the method used by Mr Carrier more than a hundred years ago, but the science and the convenience behind it is far more advanced.

How do I install an air conditioning unit?

It is not recommended that you install your own unit, especially if it’s industrial sized. You’ll want to leave that up to a bespoke air conditioning installation firm such as from New York, a company whose customer service is beyond reproach. In fact wherever possible, try to go with a ‘local’ company as they will generally be cheaper, friendlier and more reliable than the larger, faceless conglomerates.

What do I do if my air conditioning unit breaks down?

Although you might now understand the basics of how air conditioning works, attempting to fix a unit yourself is still far from advisable. Air conditioners are incredibly complicated, mechanical systems which depend on numerous specific conditions in order to work effectively. The most common cause of air conditioner failure is a leaking of refrigerant, a problem which obviously cannot be solved by a layman. There are numerous companies who specialise in air conditioning installation and repair such as Santa Air. If possible, try using the same company who built and installed your unit as they will obviously be better equipped to deal with the problem.

As a long time plumber and heater, George Torres has installed and repaired a fair few industrial air conditioning systems in his time and knows a lot of them inside and out.

Image Credit:
Naypong – FreeDigitalaPhotos.Net

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  1. Definitely get a pro to install your air conditioner. I tried to install one in our place once and it didn’t go so well. I ended up having to call a company to fix what I messed up.

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