How Does an Air Conditioner Work?

July 18, 2016

The popular season is in full swing with record heat across the country, and with many houses having some kind of air conditioner, it’s the best way to get out of the heat. As you are relaxing in your comfortably cool home or office, appreciating that your air conditioner works, let’s gain some insight at how a normal AC system works.

The Basics

Your air conditioner runs the just like your refrigerator, but obviously rather than keeping a single space cool, it has to cool your entire home. Both use a refrigerant that changes simply from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant loop from the exterior to the interior of your house. It goes into the house as a sub-cooled liquid that evaporates and collects or soaks up heat from your indoor air, expands back into vapor, then back to the outside condensing unit where it dissipates the heat and is transferred back to a sub-cooled liquid.

The Components

Your AC system is made of four critical components: 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 situated in the garage. As warm indoor air is blown over the cold evaporator coil, heat is removed from the air…and the cooled air is blown among your home.

From the evaporator coil, the now super-heated vapor refrigerant returns to the compressor based in your outside condensing unit. The compressor raises the pressure of the vapor until it shifts into a hot, high pressure vapor. The now super-hot vapor enters the condenser coil where less hot air blows by the coil, removing heat to the outdoors, and changes 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 redone.

Your air conditioner is a consistent loop of physics at work. We know the important thing to you isn’t really how it works, but that it’s functioning the right way. If you’d like to think about the process or just about remaining cool, give our technicians a call at 715-301-0727. We will team up with you and the laws of physics to confirm you cool this summer.