How Does Central Air Conditioning Work?

June 14, 2021
Central Air Conditioning in Roseville, Michigan

It might be difficult to make the best choice on a new AC if you haven’t learned how AC actually works. Buildings and their occupants each have unique needs that a custom AC can be adjusted to meet. If you’re unsure of the options you have regarding AC, then our technicians are here to give you a complete overview.

This guide will help you to understand what the ideal AC for your building is and why that unit works in its specific way. All AC units work similarly, but you can choose from portable, stationary, and mid-sized modules.

Compressors and Modern Air Conditioning

At the core of air conditioning is a type of engine called a compressor. This engine is an enclosed cavity that pressurizes the air and gases it receives. Compression, as a natural force, forces gases and liquids to be reduced in volume. These gases and liquids exert energy when they’re released from a pressured state. Moving the liquids and gases of your AC unit, which are called refrigerants, around is what a compressor’s primary role in air conditioning is.

Though you’ll likely receive yours with a covering on it, a compressor looks relatively similar to a common generator. Most compressors are powered by your building’s electricity. Emergency models have fuel tanks, which enable them to run on gas during a power outage. Inside an AC compressor is a rotor, which has a spinning blade that’s intentionally engineered with an offset alignment. The rotor spins, and with the help of negative pressure, air is drawn into the compressor’s chambers.

These cavities are created by retractable walls that extend outward, creating the adjustable blades of a compressor rotor. These blades reduce in length after encountering areas within the compressor that are smaller in diameter than others. The reduction in cavity size is what slowly compresses air. A predetermined amount of pressure is achieved before it’s released to an AC unit. The output, which an AC unit uses to receive pressure, is where compressed air exits.

The Condenser Coils

The condenser coils are where the fluids of your AC unit are stored. Refrigeration relies on a fluid called refrigerant to cool your air. These refrigerants, though kept as liquids in the condenser coils, first become liquids through condensation. The fluids created, however, need to be isolated in order to keep them cool. This is why the condenser coils protect your liquid refrigerants, thus helping your AC to maintain your cold temps.

Your condenser coils are likely installed outside of your building. These coils, by staying cool, absorb heat from within your air. The heat absorbed by the condenser coils is captured by the liquids that the coils hold. That heat is then eliminated by sending it into the evaporator coils.

The Evaporator Coils

The gas refrigerant of your AC, unlike its liquid counterpart, is stored in the evaporator coils. To maintain the process of condensation, your AC must return its liquid refrigerant to its gaseous state. Gas refrigerants get compressed and condensed into a cooled liquid. The heat these liquid refrigerants absorb in the condenser coils forces them to evaporate almost instantly. The evaporator coil is where those vapors of gas enter before being compressed again.

The coils themselves, whether vapor or liquid coils, don’t hold or directly receive air from your home. The contents of your AC’s coils are separated in an enclosed container. Airflow, being achieved with fans or vents, is what pulls air over the coils. Air that passes over the evaporator coils is filtered as the cool temps of the coils extract heat.

Condensation and the Role Humidity Plays

Humidity is innately captured from the air as an air conditioner is running. You can even assess humidity levels to see how well an AC captures moisture. For example, condensation collecting on your windows doesn’t happen when your AC unit is highly efficient. Droplets might collect around that unit, but you shouldn’t see it anywhere else when your AC is on. Since AC is the process of creating condensation, moisture is captured from the air when your AC runs.

Refrigerants and What They Do

Every modern AC system has a refrigerant inside. The condenser and evaporator coils are pivotal in circulating refrigerants. Refrigerants like Freon are used because they’re converted from a liquid into a gas with a minimal amount of heat. With just a bit of coolness, refrigerant vapors return back to a liquid. Refrigerants give AC units reusable sources of gases to compress during their condensation cycles. Being that it converts to liquid, refrigerants conduct cold temps well.

Refrigerants are also the least likely concern you’ll have over the years. These fluids are usable for over a lifetime and won’t require any upgrades or cleaning. Just keep in mind that the condensation you find on the bottom of an AC unit isn’t likely to be Freon or refrigerants. It’s typically water. Your refrigerants are safely sealed within the compressor, vapor, and liquid coils.

The Necessary Chemistry of Refrigerants in Your AC

Refrigerants must condense because the heavier a gas is, the cooler it is, and this results in gases becoming cool. Fast evaporation is a quality that refrigerants must also have, for if the vapor point of a refrigerant is too high, its liquid form won’t evaporate. The key to remember regarding refrigerant is its prefix “re.” Refrigerants are re-evaporated and re-condensed in an endless cycle. The actual process of evaporation is initiated by heat in your air, and refrigerants collect heat, thus becoming gasses.

The evaporation only leaves cool air as heated particles will rise to encounter the cooling cycle again. Since the compressor consistently creates pressure, the heat absorbed by your gas refrigerants is dissipated once that gas condensates back into a liquid.

Finding the Right AC System at the Right Time

Understanding how the condensation in your AC unit removes heat equips you with the knowledge to choose an ideal unit today. No matter which unit you need, we work to get cool air into every area of your building. We also offer Macomb Township residents quality AC service and installation. No matter how you move forward, avoid costly mistakes by having a professional advise you on your next step.

From duct repairs to maintenance, you can count on us to keep your air conditioning or heating system working its best. Our work in air filtration and indoor air quality means that our NATE-certified technicians can help you find the right AC for you, and while we proudly sell Trane, Lennox, and Carrier products, we can provide service or maintenance for just about any heating or AC unit in the Macomb County and Metro Detroit area. Don’t forget to ask about our UV lamps and germicidal lights, air filtration and purification systems, duct cleaning, and more. Call [company name] to schedule an appointment or discuss a system upgrade today.

company icon