How Does Central AC Work?

There are many benefits to having a central air conditioning system in your house, but the most important one is keeping your home cool and free of excessive humidity. Not only does your AC system keep your home cool, but it also cleans the air you breathe. When the air is pulled through the air filter, airborne particles like dust, lint, allergens, and bacteria are removed. Plus, a central AC system is much quieter than a free-standing air conditioner as the compressor-bearing unit is located outside your home which keeps noise levels down. But how does a central AC system actually work? 

The AC pros at Super Heat & Air are here to walk you through it. 

Parts of an AC System 

A typical central AC system is made up of two parts, also called a split system. This system includes:

  • An Outdoor Unit: The outdoor unit contains the condenser coil, compressor, electrical components, and a fan. 
  • An Evaporator Coil: The evaporator coil is generally installed on top of the gas furnace inside your home. 
  • Refrigeration lines: These lines connect the inside and outside equipment. 
  • Refrigerant: Refrigerant is what cools your house and circulated through the refrigeration lines in between the indoor and outdoor units. 
  • Ducts: Air ducts serve as air tunnels to supply the various spaces in your home with cool air. 
  • Thermostat: A thermostat controls the entire system and allows you to set the airflow and temperature to your desired setting. 

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The Refrigeration Cycle 

Now that you know a little about your central air conditioner’s components, let’s walk through the refrigeration cycle. 

  1. The refrigerant flows through the closed system of refrigeration lines between the indoor and outdoor units. 
  2. Warm air from inside your home is pulled into the ductwork by a fan. 
  3. Refrigerant is pumped from the exterior compressor coil to the evaporator coil inside your home, where it absorbs heat from the air. 
  4. The cooled air is pushed through the ducts and vents in your home, lowering the temperature. 
  5. This cycle will repeat as often as necessary to keep your home cool and comfortable. 

Central AC in More Detail

Now that you have a basic understanding of how air conditioners work, let’s dig a little deeper into the process. 

The thermostat, which is typically mounted on a wall within your home, monitors and controls the temperature of the air in your home. The cooling process will begin when the thermostat senses that the air temperature needs to be lowered based on what temperature it is set to. The thermostat signals to the air conditioning system to start running.

Once the components on the inside and outside begin to run, the fan from the indoor unit pulls hot air from inside the home through return air ducts. This hot air passes through air filters where dust and other airborne particles are collected. 

The warm indoor air then passes over the cold evaporator coil. As the liquid refrigerant inside the evaporator coil becomes gas, the heat from the indoor air is absorbed into the refrigerant, thus cooling the hot air as it passes over the coil. The indoor unit’s blower fan then pumps the cool air through the home’s ductwork to keep you cool. 

Next, the refrigerant gas travels through a copper tube into the outside air conditioner compressor. The compressor then pressurizes the refrigerant gas and sends it to the outdoor unit’s condenser coil. 

A large fan pulls the outdoor air through the condenser coil, allowing the air to absorb heat from the home and release it outside. During this process, the refrigerant is converted back to a liquid which then travels through a copper refrigerant tube back to the indoor unit. There are passes through an expansion device which regulates the flow of refrigerant into the evaporator coil. 

The cold refrigerant absorbs more heat from the indoor air, and then the cycle continues. 

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Central AC Maintenance and Repair 

If your central AC decides to take a vacation on the hottest day of the year, do not panic, call Super Heat & Air! Our team of top HVAC technicians gets the job done right every time! If you require emergency service, we provide 24-hour AC service to the Greater Tampa Bay area for a multitude of air conditioning repairs. Broken AC got you down? Call Super Heat & Air for fast service and repairs— (813) 981-7631!