How Does An Air Conditioner Work? - Weather Master Heating & Air Conditioning

How Does An Air Conditioner Work?

How does a home's AC work?

How does an air conditioner work? It’s mystifying and complex to people who aren’t trained in the HVAC field! But today, we will answer some of your burning questions …

After all, when you know the hows, whys, terms, and definitions for A/C, it can help you perform basic maintenance on your system, and better understand a technician’s explanations.

Besides, at least here at Weather Master, we consider A/C a pretty interesting topic!


We’ll go from A to Z regarding terms … so let’s start from the very beginning.

What exactly is A/C? You know that air conditioning provides cool air to your home. But how exactly does it do that? By “conditioning” the warm air inside your home, to make it cool, and also make it less humid.

Essentially, there are two components of the A/C system that you should remember:


The compressor is machinery in your A/C system. Its job is to take a liquid called refrigerant, which is used because it can change very quickly from a liquid to a gas and from a gas to a liquid. (This really helps control temperature, which is exactly what you need in your A/C system!) The compressor’s job in this process is to turn refrigerant from a gas to a liquid.


Well, when the refrigerant turns from a gas to a liquid, all the heat from the hot refrigerant gas is released, outdoors. Then, on to the next step …


“E” is for “evaporator”!

(OK, we’ll stop acting like this is Sesame Street. Sorry!)

Releasing the heat from inside your home into the outdoors is an important part of air conditioning, achieved by the condenser. But the other important piece of machinery is the evaporator.

That’s because, right now, the refrigerant is a liquid. That means it can’t hold heat. So if this refrigerant is going to remove the heat from the air in your home and “condition” the air, something else to happen …

It needs to pass through the evaporator!

This makes the refrigerant, well, evaporate. The evaporator forces the refrigerant to change it from a liquid to a gas, and in doing so, the refrigerant can absorb the heat inside your house.

So you have your compressor, which releases heat outdoors, and then you have your evaporator, which removes heat from inside your home. In this cyclical, repeating process, it’s the same air being “conditioned” over and over again, going through the compressor and the evaporator.


Last but not least for today, we’re going to go over humidity!

That’s because, there is yet another reason why an air conditioner is called an air conditioner. Sure, it “conditions” air by making it the temperature you want. But also, you want your air to be conditioned by reducing the humidity.

In fact, when Willis Carrier invented the air conditioner back in 1906, the reason he called it an air conditioner, instead of a cooler, was because he cared more about reducing humidity than cooling the air. He worked in a printing factory, and the humid air was messing up all the pages. So he invented the air conditioner, to condition the air by dehumidifying it!

How does air get dehumidified? Well, with our good friend we just mentioned, the evaporator!

The evaporator removes heat from the air, but at the same time, it makes condensation.

You know how if you have a cold cup outdoors in summer, hot air will hit the cup, and make droplets? This is exactly like that. So, in the evaporation process, not only is hot air cooled down, but also, some of that annoying moisture is removed too.

Hopefully you’ve learned why an air conditioner is called an air conditioner. And we hope that you feel more informed about your A/C in general, too!

If you’re experiencing A/C issues in your Raleigh home, it’s time to call us! At Weather Master, we care about your indoor comfort at home. All you have to do is schedule an appointment or call us at (919) 853-7910

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