The Compressor’s Job in Your Air Conditioner

A residential central air conditioning system is an intricate device, and all its components need to work together seamlessly for the AC to keep a house cool without wasting power. It’s fair to say that all the parts of an AC are equally important. But it’s also fair to single out the compressor since the job it does is the key to how an air conditioner cools a house. It’s also the component that is the most expensive to replace if it breaks down. A burnt-out compressor often means the entire air conditioner must be replaced.

We’re going to take a closer look at your home’s air conditioning system and the job of its compressor. We hope this will help you understand the importance of keeping up with regular maintenance as well as air conditioning repair in Austin, TX so you won’t end up with an emergency due to a busted compressor.


Starting at the top: an air conditioning system provides cooling for a house by moving heat out of the air inside it. This process is called heat exchange, and the medium for heat exchange is refrigerant, a blend of chemicals that switches easily between liquid and gaseous states. When the refrigerant evaporates and turns from a cold liquid into a warm gas, it draws heat from the indoor air. When it condenses and turns from a hot gas into a cool liquid, it releases this heat to the outside air. The evaporating and condensing occur along with two sets of coils in the air conditioner.

But wait… did you notice a step missing? After the refrigerant evaporates into a warm gas, it next shows up as a hot gas. And then the cool liquid becomes a cold liquid before it gets back to the indoor coil. What happens between to make the changes? This is where the compressor does its vital job.

The warm gas from the indoor coil enters the compressor through a suction line. Inside the compressor are a series of chambers where the refrigerant gas is, well, compressed. This is done similar to the pistons in a car motor. When the volume of the gas is reduced, it increases the gas’s pressure and this raises its temperature. The high-pressure gas now exits the compressor and moves toward the outdoor coil. Later, an expansion valve drops the pressure of the cool liquid to drop its temperature below freezing.

The compressor is, therefore, the pump or the heart that gives the refrigerant the energy necessary to circulate and carry out heat exchange. Without the refrigerant getting changed into a hot, high-pressure gas, the heat exchange process wouldn’t happen. The refrigerant wouldn’t move and wouldn’t condense—and the house wouldn’t receive any cooling.

The motor driving the compressor does the most work of any part of the AC. This is where the majority of the electrical power to operate the air conditioner goes, and the reason you see higher electrical bills during periods when you use the AC the most. If the motor of the compressor burns out, the compressor is fried. Unless the compressor is still under warranty, it’s best to get a new air conditioner.

Call Intelligent Air Services in the Greater Austin Area. “The Intelligent choice today makes cents tomorrow.”