Ductless Mini Splits vs Central AC

May 16, 2024
An HVAC technician installing a mini split unit in a home

Installing a new AC unit in your home is a big decision. The average cost is $5,900, but it can range from $3,600 to $8,200, which is a hefty investment. One of the largest decisions you’ll make when choosing a new AC system is ductless mini split vs. central air conditioning.

This guide will help you understand the two options, how they work, and which may be the best fit for your home.

Table of Contents

Overview of Mini-Split and Central AC Systems

Before we compare mini-split systems to central air, let’s examine how each one works to help you decide which system is right for your home and cooling needs.

Mini-Split AC

Ductless mini AC units have indoor and outdoor units, like central air. They use refrigerant to create cool air by removing the humidity and heat from the inside air. The air is pushed through a copper tube to the outdoor unit and out of the house.

However, unlike central AC units, ductless mini splits have an indoor unit in each room you want to cool. They may be mounted on the floor, ceiling, or walls. Like central air, each unit has a fan that pushes the cool air into the room.

Central AC

Central air conditioning runs on your home’s ductwork. One central unit is outside and another inside, usually in the basement or special closet.

Central AC has a main blower fan that blows cold air into the house. Instead of blowing it directly into each room, it blows it into the ductwork, distributing the air throughout the home’s vents.

Like mini-split systems, central AC uses refrigerant to cool the indoor air and remove the heat and humidity from the house by blowing it through the outdoor unit.

Pros of Ductless Mini Splits

As you can probably imagine, ductless mini-splits have pros and cons. Here are the advantages of these newer systems.

Energy Efficiency

Ductless mini-splits can be more energy efficient simply because they lack ducts. According to the Department of Energy, duct systems lose 30% of energy, making your system work harder to keep your home cool. Since mini-splits don’t use ducts, you eliminate this concern.

Zoning Capabilities

Unlike central AC, you can choose which mini-split systems run, allowing you to zone your AC. With multiple units throughout your house, you can turn on the units of occupied rooms and keep the units in unoccupied rooms off.

This works well in homes with rooms you don’t use often. Why waste energy cooling those rooms when you don’t use them?

Flexibility with Installation

Since mini-split systems don’t use ductwork, you don’t have to worry about the complexities they present during installation. You don’t have to cut into drywall or install new ductwork if it doesn’t already exist.

Cons of Ductless Mini Splits

Like any new appliance, mini-splits have downsides to consider.

Upfront Costs

You might assume mini-splits cost less because they are ‘mini.’ However, the opposite is true. Because they are more energy efficient, they generally cost more than central AC units.

According to the Department of Energy, mini-splits cost 30% more than central AC units upfront (without ductwork).

Aesthetic Concerns

Since mini-splits have an outdoor unit and an individual unit in each room you want to cool, they can be less visually appealing. You can usually see units in each room, which can detract from its appeal.

In addition, mini-split systems have a line that runs from the indoors to the outside. The line is often visible on a home’s exterior, can usually be seen from far away, and detracts from its curb appeal.

Pros of Central Air Conditioning

When comparing mini-split systems to central air, it’s important to consider the pros and cons of central air, too. Here’s what to consider.

Lower Initial Cost

As we stated above, mini-split systems cost an average of 30% more than central air. Choosing central air means you could save money upfront. However, the unit’s energy efficiency determines if you save money on your monthly utility bills.

Whole House Cooling

Central air has ductwork that connects throughout the entire house rather than individual units in separate rooms. The connected ductwork allows the cool air to pass through several rooms at a time, making it easier to cool larger houses.

Aesthetically Pleasing

Unlike mini-split systems, central AC can be somewhat hidden. First, you don’t have units in each room. Central AC runs on the ductwork and vents in each room. Second, the outdoor unit can usually be hidden on the side or back of the house. It sits on the ground and can be disguised with landscaping around it.

Cons of Central Air Conditioning

Of course, there are some downsides to central AC, including the following:

Dependency on Ductwork

Central air conditioning requires ductwork to work effectively. If you live in an older home that doesn’t have ductwork, you must pay to have it installed.

Even if your home already has a ductwork system, it may not fit the needs of the new furnace or need repairs/cleaning. Without properly working ducts, central AC is useless.

Potential for Mold Growth

If the ductwork of a central air system isn’t properly insulated or maintained, it can lead to condensation and mold growth, which can be a health hazard.

Less Flexibility in Zoning

Because central air doesn’t have units in individual rooms, you can’t choose to cool some rooms and not others. This can complicate getting your house to the temperature you want since the air gets circulated through a much larger area.

Higher Utility Costs

Along the lines of less zoning flexibility are the higher utility costs you may incur. When you cool a larger part of your home, you use more energy, which means higher utility bills.

Factors to Consider When Making a Decision

When choosing between ductless mini-split vs central air conditioning units, there are several factors you should consider.

Climate Considerations

If you live in a climate where the weather is predominantly warm or summers get scorching hot, central air may be a better option if your home has ductwork. The central unit can cool the entire house, whereas a mini-split unit can be installed for supplemental air if certain rooms aren’t cool enough.

If, however, you live in an area where the temperatures don’t get too high, a mini-split system may provide the cooling you need in certain rooms without wasting energy cooling the entire house.

Budget and Upfront Costs

Since mini-split systems cost as much as 30% more than central AC units, your budget is a serious consideration. Mini-split systems are a serious investment upfront but may save you money on utilities down the road. Consider how much money you have to invest in the system upfront and how important saving money on energy bills is to you.

Home Layout and Size

If you have an existing home with ductwork, central AC could be a good option if it fits the current setup. If, however, you have an older home without ductwork or the existing ductwork doesn’t work with the new AC unit, you may be better off with a ductless mini-split.

The home’s size and the number of rooms you need to cool also play a role. A large home that only requires cooling in a few rooms can benefit from a mini-split, whereas a home that requires cooling throughout, whether small or large, could benefit from a central AC unit.

Long Term Efficiency

Mini-splits are known for their energy efficiency, which may save you money on your utilities in the long run. They offer comparable cooling to central AC units but use less electricity, and the units may last longer because they aren’t put under as much stress as central AC units.

Conclusion

Choosing the right air conditioner unit for your home is key to your comfort. Understanding your home and personal needs will help you choose the right system. 

When comparing the mini-split vs central air conditioner unit, it’s important to consider your home’s layout, how much cooling you need, and your budget.

When you’re ready to have a new AC unit installed in your home, find an HVAC professional near you who provides excellent service, advises you on the right system, and helps you maintain it to make it last.

FAQs

Is it cheaper to run a mini split or central AC?

It’s generally cheaper to run a mini split air conditioner because it only cools specific rooms rather than the entire house. This allows the unit to reach the desired temperature faster than a central AC unit responsible for cooling an entire house.

Which is better, split AC or central AC?

Choosing between mini-splits and central AC is a big decision, but one isn’t necessarily better. It depends on the area you need to cool, your climate, and your budget. If your home already has ductwork, a central AC unit may be more affordable upfront and provide cooling throughout your entire home. However, split AC units may be more economical in the long run if your home doesn’t have ductwork or you only need to cool a room or two.

Are mini splits more efficient than AC units?

Because mini splits cool a single room versus an entire house, they are more efficient than central AC units. This allows them to use less electricity and puts less stress on the unit, potentially making it last longer.

Other key reasons why mini-splits are more energy-efficient include:

Do mini-splits use a lot of electricity?

The average mini-split uses 500 to 1500 watts per hour, while central AC units use between 3,000 and 3,500 watts per hour. Thus, mini-splits use about half of the electricity central AC units use, but it depends on how many mini-split units you have running at once.

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