We’ve grown dependent on machines. If our cars won’t start, we call in to work. If our computers go down, we’re forced to do math with archaic pencil and paper. If our air conditioners stop working though- well, we don’t like to think about that unless we have to. The world grinds to a halt with the failure of these indispensable cold air dispensers. These machines are literally built to understand and suit our every whim, so let’s return the favor, and at least seek to understand what makes them tick, shall we?

There aren’t really many differences between an air conditioning unit and the refrigerator in your kitchen, except that your home isn’t a box, at least in most cases. If you lived in a box, though, would you really have an air conditioner anyway? No matter if you live in a downtown high rise, a wigwam, or a Kenmore box, the principles behind keeping it comfortable on a hot summer’s day are the same as with a refrigerator: air is pulled out, cooled, and then cycled back in. This process is then repeated over and over until the boss, the thermostat, is satisfied.

An air conditioning system consists of a compressor that condenses cool liquid Freon into a hot gaseous form, and a pump to push the gas through a winding pipe with enough surface area to dissipate the heat and cool the gas back a into a liquid. The liquid is then forced through an expansion valve to put the Freon back into a cold, low-pressure gas form. The cold gas is then run through another long, winding pipe, which cools the air around the pipe, and warms the Freon up, just in time to be compressed into hot gaseous form to start the whole cycle again. Freon does the high-pressure job of getting crushed, heated, then expanded and cooled, all day and night, and rarely complains. Thanks Freon.

Air conditioning units usually have an air filtration ingredient too, in the form of a filter to catch all the dust, pollen, smoke, dirt, allergens and mold spores that can really rain on a parade. Next time, we’ll learn about more efficient and eco-friendly methods of changing the natural environment for the purpose of keeping our perishables from spoiling, and just for our own comfort.

So hats off to our A/Cs. Next time you see an air conditioning unit at a cocktail party, you two will have something to talk about.