Central Air Conditioner Parts

In this guide, we’re discussing central home air conditioner systems. Many homeowners and businesses depend on a central air conditioner, but few know how they work. Some also aren’t aware of the different types of AC central unit they can install. Here, you’ll find a complete guide to central air conditioner systems.

What is a central air conditioner?

According to Popular Mechanics, it wasn’t until the 1970s that central air conditioning overtook window units in residential use. A central air conditioning unit is made up of a fan, coils and a condenser. It works by drawing in air that is then passed over the coils before the fan pushes the cooled air through the residency’s ventilation system.

Air conditioner parts

A modern central air conditioner uses two coils that you’ll find housed in an outside unit. This unit differs from a standard window air conditioner because the fan is separate, rather than being contained in one single unit. You’ll also find:

  • Thermostats
  • Air handler
  • Filters
  • Refrigerant-filled tubing
  • Evaporator coil
  • Condensing tray
  • Condensate drain
  • Air ducts

How air conditioners work

A sequence of events begins when the thermostat signals the central air conditioner system to lower a space’s air temperature. The air handler turns on and begins drawing air through air return ducts from various areas of the home. That air pushes through one or more air filters. Then, the air passes over coils or tubing cooled by the refrigerant. Once it passes over these, the fan pushes the cooled air through the home’s ductwork, lowering the air temperature in the home.

Types of central air conditioners

In this section, we’ll discuss the different types of central air conditioner systems. These include a split system central air conditioner or packaged systems. Telling the difference between the two types of home air conditioner systems is simple. However, we’re going to take a more in-depth look to help you better understand these differences.

Split system central air conditioners

A split system central air conditioner has two different components. The outdoor cabinet contains the compressor and condenser. A separate indoor cabinet is where you’ll find the evaporator. If your home has a furnace, but no AC central unit, a split system home air conditioner is your best option.

There are several benefits to having a split system central air conditioner unit, including:

  • Many systems feature high-efficiency ratings
  • An HVAC professional can install them in attics, closets, garages and other areas of the home
  • Many split systems operate at lower decibels

Split system central air conditioners consist of five parts:

  • Indoor air handler
  • Outdoor air conditioner
  • Either a programmable or non-programmable thermostat
  • Indoor air filtration or humidity control component
  • A ductwork system throughout the home to move air-conditioned air to rooms

Compared to a packaged system, a split air conditioner system takes up more room. Split-system central air conditioners are the most common due to many homes’ size and structure. The reason a split system has its name is that it consists of two separate units, whereby one is inside your home and one is outside.

Packaged system central air conditioners

When you look at a packaged system central air conditioner, you’ll find a single cabinet containing the:

  • Compressor
  • Condenser
  • Evaporator

These cabinets typically install on a concrete slab next to the home’s foundation or on the house’s rooftop. If all the components aren’t housed in a single unit or cabinet, then you’re working with a split-system.

The packaged air conditioner system connects to return or air supply ducts coming from inside the home through its roof or exterior wall. The benefit of installing a packaged unit is that they often include a natural gas furnace or electric heating coils. That way, you’re combining a central heater and air conditioner, thus eliminating the need for separate units.

Air conditioner energy efficiency

According to the U.S. Energy Information Administration (EIA), residential central air conditioner units must meet new minimums regarding energy efficiency standards starting in 2023. The EIC further states that the most recent standards for energy efficiency began in 2015. This continues efforts that started with the Energy Policy and Conservation Act (EPCA) that was enacted on December 22, 1975, in response to a need to conserve oil and increase energy efficiency.

The NAECA, National Appliance Energy Conservation Act of 1987, enacted to develop minimum energy efficiency standards, went into effect for central air conditioners and other appliances in 1992. That includes SEER, Seasonal Energy Efficiency Ratio, which provides for a minimum of 14 SEER for northern states and at least 15 SEER in southern states.

According to Energy Star, the SEER rating measures a central air conditioner’s efficiency. If it has a higher SEER rating, that means it’s a more efficient home air conditioner system. During a typical cooling season, the SEER rating measures a central air conditioner’s total cooling.

Energy Star further states that choosing a central air conditioner with an Energy Star logo means it must pass strict government efficiency guidelines the U.S. Environmental Protection Agency sets. That means you’ll find a central air conditioner with a higher SEER rating while simultaneously using less energy.

Frequently Asked Questions

What is a central air conditioning unit?

A central air conditioner is a system whereby a central location cools air and then uses fans and ductwork to distribute air to and from rooms. The entire air conditioner process is thanks to the AC central unit’s compressor. When refrigerant gas compresses, it can create cool air by discharging heat from the home.

How does central AC work?

A central air conditioner works by cooling the warm air inside your home by blowing that warm air across the unit’s evaporator coil. Then, that air transfers to the coil containing refrigerant. That process is how the air cools. Once the process completes, the refrigerant pumps back to the compressor, allowing the entire process can begin again. The air the refrigerant cools moves to the inside spaces of your home when a fan pushes it through a series of duct work. This process also involves warm air blowing out of the house.

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