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How Do Ductless Air Conditioners Work?

How Do Ductless Air Conditioners Work?


Unlike traditional air conditioning systems that use ductwork to transport cold air throughout your home, a ductless air conditioner cools the air in the area it’s located, eliminating the need for ducts. When a traditional HVAC system has a high air conditioner cost or is impractical to install, utilizing targeted cooling and heating from ductless units is an easy and efficient solution. They are also cost-effective, versatile, and less noisy than the original air cooling systems.

How Do Air Conditioners Work?

Instead of air flowing through an internal air handler to cool, a ductless air conditioning system consists of a compressor outdoors and an indoor air handler. Coils that contain refrigerant run through each of these units, and copper tubing connects them. In traditional systems, the air handler—a box into which warm air flows and is cooled, then expelled—is located centrally, frequently in an attic. The cooler air is distributed throughout the house or building through a series of ducts located behind the walls’ sheetrock or flooring.

Ductless air conditioners became popular in Japan in the 1950s. It became clear that standard air conditioning systems imported from America wouldn’t work in Japan’s smaller homes and close-knit neighborhoods. The ductless air conditioning system was a solution to this dilemma because they are smaller, more efficient, and less noisy than the complicated American systems with extensive ductwork. Americans soon took note of these systems’ versatility and adopted ductless air conditioners as a suitable alternative to conventional HVAC units in small homes.

Components of a Ductless Air Conditioner

There are four major parts of the ductless air conditioning system—the indoor unit, the outdoor unit, the connection line, and the remote. You can have up to four units connecting to one outdoor compressor, and the size of the indoor unit depends on how much square footage you need to cool or heat.

  • Indoor Unit  This is also referred to as the blower, the evaporator, or the air handler. This component sucks warm air and moisture from the room and blows out cooler air. It has a streamlined design, with the average indoor mini split unit measuring 32” W x 12” H x 9” D. You can install the indoor unit recessed into your wall or ceiling, mounted flush with the ceiling at a high point on the wall, or near the floor.
  • Outdoor Unit – Also called the condenser or compressor, the outdoor component is how the ductless air conditioner dissipates the heat collected from inside the house. The refrigerant in the conduits attaching the indoor units to the outdoor units discards the heat and moisture into the condenser, and then into the surrounding atmosphere.
  • Conduit – Constructed of copper tubing and containing refrigerant, the lines go from the outdoor unit to all indoor units to collect heat and moisture, and then make a round trip to get rid of the heat and humidity.
  • Remote Control – The owner can control each room’s temperature with a Wi-Fi-powered remote control. With a simple user-interface and wall mounting capabilities, the remote is a simple alternative to the traditional wall thermostat.

air conditioning unit outside building

Reasons to Go Ductless

If you live in an older home, you’re familiar with the infrequent but annoying too-hot or too-cold spots in your home. When foundations settle and wood ages, your house subtly changes shape, allowing drafts to develop. Because ductless air conditioning systems employ targeted air conditioning, it’s easy to eradicate any uneven areas in your house and enjoy consistent temperatures in every room.

Maybe you have a basement rec room that is always chilly, or your children’s rooms on the top floor get stuffy. Ductless air conditioning can solve these issues with lines that easily reach the outside compressor.

While ductless air conditioning systems work well in older buildings, they are also a welcome addition to new buildings. More recent construction trends are geared toward smaller, more energy-efficient homes, and a ductless system fits these expectations perfectly. In homes under 2,000 square feet, a ductless air system can handle all your heating and cooling needs at a minimal cost and with less noise.

Make sure to check with an HVAC expert like those at ComfortUp to check the air conditioner cost and whether your home, business, or institution is suitable for mini split installation.

mini split air flow illustration

The Final Word

If you’d like to update your home’s existing ductwork and air conditioning system, consider a ductless air conditioner. They’re the most cost-effective heating and cooling system in the long run, a green alternative, and virtually noiseless, and they can adapt to all conditions of your building.

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