How Does an Air Conditioner Work?

July 18, 2016

The popular season is in full swing with record temps across the country, and with the vast majority of homes having some kind of air conditioner, it’s the ideal way to get out of the heat. As you are sitting in your comfortably cool home or office, thankful that your air conditioner works, let’s look at how a normal AC system works.

The Basics

Your air conditioner works the similar to your refrigerator, but clearly compared to keeping a single space cool, it has to effectively provide cooler air to your whole home. Both use a refrigerant that changes easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant ring from the outside to the interior of your house. It goes into the home as a sub-cooled liquid that evaporates and collects or soaks up heat from the air within your house, expands back into vapor, then heads to the outside condensing unit where it dissipates the heat and is changed back to a sub-cooled liquid.

The Components

Your AC system is made of four main pieces: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The part where your refrigerant evaporates from a sub-cooled liquid to a super-heated vapor is called the evaporator coil, which may be inside your home, in your attic, or in your garage. As warm indoor air is carried over the cold evaporator coil, heat is pulled from the air…and the colder air is pushed within your house.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor located in your outdoor condensing unit. The compressor increases the pressure of the vapor until it shifts into a hot, high pressure vapor. The now super-hot vapor meets the condenser coil where less hot air blows by the coil, moving heat to the outdoors, and switches the refrigerant to a sub-cooled liquid. The sub-cooled liquid refrigerant is sent to the indoor evaporator coil where, through an expansion valve or metering device, the process is repeated.

Your HVAC system is a constant loop of physics at work. We realize the important thing to you likely isn’t what happens behind the scenes, but that it’s operating the right way. If you’d like to talk science or just about staying cool, give our experts a call at 402-318-5351. We will work with you and the laws of physics to confirm you comfortable this season.