How Does an Air Conditioner Work?

The popular season has arrived with record highs across the country, and with many houses having some kind of air conditioner, it’s the best way to escape the sun. As you are unwinding in your comfortably cool home or office, appreciating that your air conditioner works, let’s gain some insight at how an average central heating and cooling 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 cool your entire home. Both use a refrigerant that converts easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant ring from the outdoors to the inside of your home. It goes into the house as a sub-cooled liquid that evaporates and collects or absorbs heat from your indoor air, 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 key 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 indoors, in your attic, or situated in the garage. As warm indoor air is moved across the cold evaporator coil, heat is removed from the air…and the cooler air is pushed within your indoor space.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor stationed in your outdoor condensing unit. The compressor enhances the pressure of the vapor until it changes into a hot, high pressure vapor. The now super-hot vapor meets the condenser coil where a smaller amount 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 pushed 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 processes. We realize the important thing to you likely isn’t what happens behind the scenes, but that it’s functioning the right way. If you’d like to know the inner workings or just about keeping cool, give our professionals a call at 314-838-9800. We will work with you and the laws of physics to ensure you happy this season.

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