How Does an Air Conditioner Work?

Summer is here with record temps 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 runs well, let’s gain some insight at how a normal central heating and cooling system works.

The Basics

Your air conditioner works the just like your refrigerator, but obviously rather than keeping a little space cool, it has to work to cool down your whole house. Both use a refrigerant that converts swiftly from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a consistent loop from the outdoors to indoors. It goes into the house as a sub-cooled liquid that evaporates and gathers or absorbs heat from the air within your house, expands back into vapor, then returns 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 created out of four key pieces: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The component 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 over the cold evaporator coil, heat is detached from the air…and the cooler air is pushed within your house.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor located in your exterior condensing unit. The compressor increases the pressure of the vapor until it changes into a hot, high pressure vapor. The now super-hot vapor enters the condenser coil where a smaller amount hot air blows by the coil, moving 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 replicated.

Your HVAC system is an endless loop of movement. We realize the important thing to you isn’t really how it works, but that it’s working correctly. If you’d like to know the inner workings or just about staying cool, give our experts a call at 815-410-1231. We will work with you and the laws of physics to confirm you cool this time around.

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