How Does Air Conditioning Work? Lessons from Your Clearwater AC Experts

How Does Air Conditioning Work? Lessons from Your Clearwater AC Experts

Can you imagine living in the Tampa Bay area without air conditioning?

It’s hard to believe that less than one hundred years ago, cooled indoor air was an uncommon – and even controversial – commodity. What was once a class differentiator is now a must-have for Florida homeowners and U.S. households, and certified HVAC professionals around the globe are trusted to maintain, service and install new central AC, window and ductless systems.

But have you ever stopped to think about how your AC system works to cool your home? Read more from your Clearwater heating and air experts to learn where it all began, how warm air becomes cold, and what keeps your AC system running.

The History of Air Conditioning

In the early 20th century, young electrician Willis Carrier coined the term “air conditioning” after designing his “Apparatus for Treating Air” for a Brooklyn publishing company in 1902, with hopes of reducing indoor humidity that impacted printing over the summer1.

Long before, however, refrigeration technology was engineered by innovators like University of Glasgow professor William Cullen, who evaporated liquids in a vacuum in 1748, and Florida doctor John Gorrie, who built the first ice machine to help his yellow fever patients feel more comfortable in 1851. Three decades later, naval engineers also developed a method to keep President James A. Garfield cool after being wounded by gunshot2.

In the early 1900s, the air-cooling technology began to spread. Frigidaire sold the first household “room cooler” in 1929, and H.H. Schultz and J.Q. Sherman marketed an AC that leaned against the windowsill2.

Then at the 1939 World’s Fair, AC made its first public debut at Carrier’s “Igloo of Tomorrow” expo, where visitors experienced air conditioning for the first time, boosting consumer interest. Over the next two decades, AC systems shrank in size, ads targeted women in the home, and the U.S. Weather Bureau created what we now know as the “heat index,” which measures temperature and humidity combined2.

By the 1960s, millions of air conditioners were sold every year in the U.S., and windows across cities and suburbs were sealed by AC units. Today, nearly 90% of households across the U.S. have an AC unit or central air3.

How do AC systems work?

Thanks to these innovative AC pioneers, the concept of air conditioning is fairly simple: your AC system takes the warm and humid air from inside your home, brings it outside, and then replaces it with cold air.

Modern central AC systems work with several key components4:

  • An outside unit made up of the condenser coil, compressor, fan and electrical components
  • An indoor unit made up of evaporator coils, usually installed in the attic or hallway closet in most Florida homes
  • Pipes that connect your indoor and outdoor AC equipment
  • Refrigerant (freon), a substance that circulates through your outside and inside unit
  • Ductwork that takes in and delivers air to different rooms through vents in your home
  • A thermostat that controls your desired temperature
How does warm air become cold?

When your AC system is turned on, the refrigeration cycle is constantly working to cool your home. Here’s how a new AC unit works4:

  • Using electricity, refrigerant flows through your pipes – or refrigeration lines – between the indoor and outdoor unit
  • Heat from inside your home is pulled into the ductwork by a motorized fan
  • The refrigerant circulates from the outdoor compressor coils to the indoor evaporator coils, converting from liquid to gas, then back to a liquid again in a process called phase conversion
  • This process helps the coils become very cold and remove humidity from the air
  • As the hot, humid air flows into the system, cool and comfortable air flows back through the ductwork into your home through air vents
  • This air conditioning process continues until the temperature inside your home matches the setting on your thermostat

Much like central air, window AC units or ductless mini-split systems follow a similar cooling cycle, but on a smaller scale and without ductwork, since these units usually reside in individual spaces, Florida sunrooms and porches.

What keeps my AC running?

For this AC process to keep your home consistently cool, all of these components must be working properly.

That’s why at Air Care, we recommend a bi-annual AC system tune-up, where our certified HVAC professionals:

  • Check and clean burners
  • Inspect air filters (clean or replace if needed)
  • Check carbon monoxide levels
  • Adjust refrigerant levels
  • Check contactors and relays for wear
  • Inspect pressure and temperature
  • Inspect safety devices and controls
  • Test emergency shut-offs
  • Inspect ductwork
  • Flush and clean drain line and trap
  • Inspect heat exchanger for leaks and cracks
  • Tighten electrical connections

Learn more about preventative maintenance service and special offers.

Call Us for Service or New AC System Installations

At Air Care, we keep our customer’s top interests in mind and strive to deliver quality service with our 100% customer satisfaction commitment.


In addition to AC maintenance and repairs, our HVAC professionals are experts at new AC installations across all brands including Rheem – one of the most reliable and quality brands in the heating and cooling industry. As a Rheem Pro Partner, our HVAC technicians are trained and certified in the latest Rheem products, which are tested in the toughest weather conditions. Click the video below to learn more.

Give us a call today to request service or get a quote on a new HVAC installation in Pinellas, Southern Pasco and Western Hillsborough counties.

“Air Care provides fast, friendly AC repair services. When your air conditioner breaks in the middle of a Largo summer, you want it fixed immediately. Some AC repair companies do not answer their phones, and some want to schedule later visits. Air Care wants to help you the same day you call in. I would definitely recommend them to anyone needing help.”
– David from Largo, Florida


[1] Smithsonian Magazine: The Unexpected History of the Air Conditioner
[2] The Atlantic: The Moral History of Air Conditioning
[3] Energy Information Administration’s Residential Energy Consumption Survey, 2011
[4] How Stuff Works: AC Units & Goodman: Heating & Cooling 101