How Does an Air Conditioner Work?

July 18, 2016

Summer has arrived with record temps across the country, and with the vast majority of homes having some kind of air conditioner, it’s the most effective way to beat the heat. As you are sitting in your comfortably cool home or office, grateful that your air conditioner runs well, let’s look at how an average central heating and cooling system works.

The Basics

Your air conditioner operates the just like your refrigerator, but clearly instead of keeping a little space cool, it has to work to cool down your whole house. Both use a refrigerant that adapts simply 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 house as a sub-cooled liquid that evaporates and assembles or absorbs heat from the air in your home, expands back into vapor, then back to the outside condensing unit where it dissipates the heat and is switched back to a sub-cooled liquid.

The Components

Your AC system is built of four critical parts: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The piece 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 moved over the cold evaporator coil, heat is pulled from the air…and the cooled air is blown throughout your house.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor based 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, removing 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 AC system is a constant loop of movement. We realize the important thing to you likely isn’t what happens behind the scenes, but that it’s working successfully. If you’d like to think about the process or just about staying cool, give our experts a call at 715-318-6728. We will team up with you and the laws of physics to ensure you happy this season.