Buying Guide

How Do Ductless Air Conditioners Work

How Do Ductless Air Conditioners Work?
An air conditioner unit outside the house

Ductless mini-split air conditioners work similar to conventional air duct systems, but there are a few main differences. Before you can understand mini-split systems, it’s important to make sense of how traditional models work. 


In a standard air conditioning system, the indoor unit is typically located in your attic or in a closet. Ducts push and pull air to this central location, cooling and delivering it rooms in your home through the vent system. 


In a mini-split system, you have individual indoor units located in each room. Instead of pushing and pulling air to a central indoor unit, each room will handle its own cooling needs through the indoor unit.

Do They Have Enough Cooling Power?
A living room featuring a ductless air conditioner

Some homeowners worry they won’t be able to properly power mini splits to cool their home. While the individual indoor units may seem small, it’s important to remember they only have to cool a single room, not your whole home. This makes the cooling much easier.


When considering mini-split installation, you’ll need to choose the correct BTU capacity for your room. In general, the larger the room, the more BTUs per hour you’ll need. Mini-split systems come in a variety of sizes, so finding that will work is simple once you have your room measurements.


12,000 BTU mini split

18,000 BTU mini split

24,000 BTU mini split

Benefits of Mini-Split Systems
A bedroom featuring a ductless air conditioner

Ductless air conditioning systems are becoming more common in single-family homes. While the units themselves typically cost a bit more than ducted AC components, that cost is offset by a absence of ductwork installation and higher energy efficiency during operation. Here are a few main reasons builders and homeowners choose to install mini splits:

  • You don’t need existing ductwork. With a mini-split system, you can add air conditioning to your home without ductwork in place.
  • Affordability. Choosing a mini-split system is more affordable if you’re retrofitting your home or building from the ground up without ductwork. It also takes less time to install a mini-split system.
  • Heating capabilities. Mini split heat pumps are becoming increasingly more common. That means you can get both heating and cooling from the same system.
  • Versatility. Mini-split systems can be installed in a variety of orientations based on your home’s configuration. Floor-mount, ceiling-recessed and horizontal-ducted configurations are common.
  • Easy installation. Ductless air conditioning systems are easier to install and weigh less. 
  • Energy efficiency. Ductless systems don’t lose hot or cold air due to duct leakage. Most mini-split systems are approximately 20% to 30% more efficient on average.

For many homeowners, mini-split systems will provide adequate cooling and serve as a budget-friendly alternative to traditional air conditioning installations. Designed to be energy efficient, mini-split systems are also a smart buy for the eco-conscious homeowner.