How Does an Air Conditioner Work?

The popular season is here with record highs across the country, and with a lot households having some type of air conditioner, it’s the most effective way to beat the heat. As you are sitting in your comfortably cool home or office, appreciating that your air conditioner functions, let’s take a peek at how an average central heating and cooling system works.

The Basics

Your air conditioner runs the just like your refrigerator, but understandably compared to keeping a little space cool, it has to work to cool down your whole house. Both use a refrigerant that adapts easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a regular loop from the outside to the interior of your house. It goes into the house as a sub-cooled liquid that evaporates and collects or takes in heat from the air in your home, expands back into vapor, then returns 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 built of four main components: 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 indoors, in your attic, or located in the garage. As warm indoor air is carried throughout the cold evaporator coil, heat is pulled from the air…and the cooler air is blown among your indoor space.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor stationed in your outside condensing unit. The compressor increases the pressure of the vapor until it shifts into a hot, high pressure vapor. The now super-hot vapor enters the condenser coil where a lower amount hot air blows by the coil, moving heat to the outdoors, and returns 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 replicated.

Your AC system is a constant loop of physics at work. We realize the important thing to you isn’t really how it works, but that it’s working correctly. If you’d like to talk science or just about remaining cool, give our professionals a call at 847-306-8990. We will work with you and the laws of physics to confirm you cool this summer.

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