The main difference between a mini-split and a central air conditioner is that a mini spit is designed to cool a small section of the house, like a single room. A central air conditioner is designed to provide cooling to a whole house.
Using air conditioning throughout the blazing summer months can make your home more bearable and comfortable. But between mini-split vs. central air conditioner, which one is better?
This article delves deeper into the specifics of each option to help you pick which is best for you, so keep reading to learn more!
How a Mini-Split Works
Mini-split air conditioning systems are popular for homes with limited space. They work using the same science as a central air conditioner.
It pulls warm air across cold evaporator coils filled with refrigerant, cooling the air. Then, it blows the cold air into your home. At the same time, the now warmer refrigerant within the coils transfers the heat outside to the outdoor condenser unit.
People mainly use them to cool a single room, similar to the purpose of a window air conditioner. However, mini-splits also have a separate outdoor unit. And unlike central air conditioning, you don’t need ductwork.
The indoor unit of the mini-split has the blower and evaporator, which pulls in warm air from the room and puffs out cooled air. The cool air returns directly to the room where the unit is installed. Compared to moving through ductwork and traveling throughout the house.
On the other hand, the outdoor unit, which consists of the condenser, receives the unwanted heat from inside and releases it into the outdoor environment.
Pros and Cons of a Mini-Split
- Easy installation
- Superb cooling efficiency
- Great for small rooms
- Ability to control individual rooms
- Fewer costs over lifespan
- Fairly quiet
- Various design options
- Can provide heating in the winter
- Does not require ductwork
- Indoor unit isn’t attractive, can be an eyesore or ruin feng shui
- Pricy upfront cost if installing multiple units
- Poor ventilation
- Not always the best choice for larger spaces
Installing a mini-split is quick and easy compared to a central air conditioning unit. Since you don’t need to worry about ductwork, the only requirement is mounting a wall unit and running electrical and refrigerant lines through the wall to the outdoor unit.
Note: Depending on how many units you install, it may take less than a day to complete the entire installation process.
The refrigerant lines and cabling that joins the indoor and outdoor units are generally easy to feed through the wall.
It simply requires a three-inch hole in the wall, which is easy enough to drill. And since it’s a small hole, you don’t need to worry about the labor involved with reconstructing walls or ceilings surrounding ducts, like you would with a central AC unit.
Boosted Energy Efficiency
Ductless mini-split heat pumps are the most energy-efficient way to cool your home. Remember, they don’t have ductwork. Instead, they pump cool air directly into the room or zone they’re cooling. Long runs of ductwork lead to energy loss.
The loss incurred as the air travels through ductwork in a central air conditioning system can account for up to 30% of energy consumption. Holes, gaps, poor insulation, and cracks in the ductwork further exacerbate the issue, leading to higher rates of energy loss.
With a mini-split, the air is delivered straight from the unit into the intended area. With no ductwork, energy efficiency jumps. An obvious benefit is lower electricity costs.
Great Choice for Small Rooms
If you have small, disconnected rooms from the rest of your home, mini-splits are an excellent choice. You could install a mini-split in a work-shed, shop, garage, basement, finished attic, or anywhere else where the ductwork in your home can’t reach.
Ability to Control Individual Room Temperatures
Mini-splits in each room in your house allow for better regulation of temperatures in each room. Considering many people have vastly different opinions on the perfect temperature, these units can be a great solution to the issue of who has control over the thermostat.
In addition, you can turn on each unit only when you need it. Instead of kicking on the unit controlling your whole home, you can cool/heat the rooms you are actively in, resulting in more cost savings.
Suppose you want to cool three zones (rooms or areas in your home). Adding additional indoor units to your home is easy. Most manufacturers allow you to connect two, three, or more indoor units to a single outdoor unit (condenser).
This allows homeowners to cost-effectively control the temperature of multiple zones while minimizing their costs and installation work.
Fewer Lifespan Costs
Although the upfront cost of mini-split AC units is high compared to the central AC units, they tend to cost less over their lifespan. They’re more energy-efficient and usually are less expensive to maintain than central AC.
Produces Minimal Noise
Ductless air conditioners produce minimal noise when producing a comfortable environment in your home.
The fans run at low speeds, ensuring the system doesn’t interrupt your day. Typically, they are no louder than 50 decibels, quieter than light rain showers.
Several Design Options
Mini-splits mounted on the wall can be an eyesore. Consider a concealed mini-split that flush mounts in your wall or ceiling if you’re looking for something more in-line with your aesthetic and decor preferences. Or, you also have the option of a floor-mounted mini-split.
Depending on the mini-split option you choose, you may not like the final look. Large wall-mounted mini-splits can feel intrusive and out-of-place, throwing off the design of your room.
Luckily, there are various design options to accommodate your interior design needs.
Mini-splits aren’t the best choice for ventilation. Since these units pull air already present inside your home, bacteria, dust, and bacteria don’t get filtered well.
Compared to central air conditioners, mini-split units don’t have good air filters. Typically they are very thin and get clogged quickly. With a central AC unit, you can install a MERV or HEPA filter to improve your indoor air quality.
The system doesn’t pull fresh air from outside, which may be a problem for some folks. To address the problem, you could always consider adding an air purifier.
Not Always Suitable for Large Areas
Mini-splits aren’t intended for use in large areas. The units are best suited to smaller areas due to their limited cooling capacity. If you have a large room, you may need a fan or two to circulate the cool air. Or you might need multiple indoor units, which will drive up your costs.
How a Central Air Conditioner Works
Central air conditioners use the same general concept as mini-splits: whisk warm air away and replace it with cooled air. However, unlike mini-splits, central AC systems require ducts, supply vents, and return vents to circulate cool air throughout your home.
The entire system consists of an indoor unit and an outdoor unit. The latter has a condenser and also houses the compressor. On the other hand, the indoor unit is the air handler; it has a blower, evaporator coils, and air filter.
The blower sucks in warm air from your house, sending it to the air handler, which filters and cools the air as it passes over the evaporator coils. The evaporators coils contain compressed refrigerant gas. As the air blows over these coils, the heat transfers from the air to the refrigerant.
The now-warm refrigerant starts its journey to the outdoor unit while the blower circulates the cold air through the supply ducts in the rooms of your home.
Central air conditioners are an excellent pick for homes with existing ductwork. However, if your home doesn’t already have ductwork, they are not a great option. It is costly to add ducts to a finished home.
It is possible to add ducts for the central AC unit. However, a mini-split system would be easier and less costly.
Pros and Cons of a Central Air Conditioner
- Great for large homes
- Unobtrusive, won’t impede your home’s aesthetics
- Clean, ventilated air cycling
- Better filtering
- Better home comfort
- Consistent home temperature
- Requires extensive ductwork
- High operational costs
- More maintenance
- Maintenance costs more
- Higher energy bills
- Requires ductwork
Great for Larger Homes
Central air conditioning systems are the ideal choice for larger homes. An appropriately-sized unit can quickly meet the cooling needs of any size home.
Instead of cooling individual rooms, central ACs can keep your entire home cool and comfortable, even in sweltering summer months. Plus, they provide a more consistent temperature, free of “hot spots” and “cold spots,” assuming they are sized correctly for the home.
Unobtrusive and Out of the Way
Generally, the indoor central AC unit is hidden in a basement, garage, utility room, or attic. As such, the indoor unit won’t disrupt the aesthetics or decor of your home like a wall-mounted mini-split would.
The outdoor unit may be somewhat of an eyesore, but you can always hide it with artfully planted shrubs, plants, or a wooden enclosure.
Lower Initial Costs
Central air conditioning systems cost less upfront than mini-splits per BTU of cooling capacity, aside from ductwork, vents, and installation costs. If you already have existing ductwork, you’ve already won half the battle.
Of course, the quality and age of your ductwork may affect the final price, but usually, it’s much cheaper than starting from scratch.
Central AC units cost up to 30% less than mini-splits per BTU of cooling power, which can be a deciding factor for some homeowners.
Besides providing a cool, comfortable environment throughout your home, central air conditioners also provide better filtration and humidity control.
The ducted system pulls unfiltered air from your home through the supply vents and the AC unit’s air filter. Central AC units have much larger, thicker, and higher efficiency filters than ductless mini-splits.
Many central AC units can fit 1-4″ thick MERV filters that can substantially reduce the amount of dust, pollen, mold, viruses, bacteria, germs, and other particles in your home’s air.
This helps improve the overall air quality in your home, which translates to fewer pollutants throughout your home.
Requires Extensive Ductwork
Ductwork installation makes up a sizable chunk of the total cost of installing a new central air conditioning system. However, this isn’t really an issue if you have existing ductwork.
However, installing ductwork is a considerable renovation if you’re starting from scratch. The process involves opening up walls to install ducts throughout your home, which can be a costly and lengthy process.
High Operational Costs
The cost of operating a central air conditioning system can rack up quickly. There is significant energy loss associated with ductwork. This leads to higher energy consumption, in turn driving up your electricity bills.
If your ducts aren’t properly insulated, the cost will continue to rise due to higher levels of energy loss.
In addition, cooling your entire home can be a disadvantage, particularly when you don’t use all of the rooms at once. Like, when your kids are away for summer camp or college. But using the central air conditioner solely to cool one or two rooms in your home can also lead to a dramatic influx in your energy bills.
Note: Closing or blocking supply vents in an attempt to cool fewer rooms in your home will cause your AC unit to short cycle.
Short cycling is when your AC unit turns on and off too often, in this case, because it is cooling the smaller area too fast. Short cycling uses a ton of energy and puts a lot of wear and tear on the AC unit. Both can lead to expensive bills.
If you find yourself regularly using the central air conditioner to cool a room or two, you may want to consider HVAC zoning. It can help safely combat the issue to keep your bills low.
Ductwork Requires Regular Maintenance
To avoid additional energy loss via cracks, gaps, or holes in the ductwork, you must maintain it well. This requires sealing leaks as they occur, cleaning them regularly, and adding insulation.
If you dismiss the need for maintenance, you may end up with a costly repair bill. Although it can be pricey, it’s usually best to stay on top of maintenance requirements since it’s cheaper in the long run.
How To Decide on a Central Air Conditioner or Mini Split
Now that we’ve addressed both options and the pros and cons of each, we have more clarity to make an educated decision. However, deciding if a mini-split or central AC system is better for your home is challenging.
There are a few primary areas of consideration that may help you decide which option is best for you. Here are some important areas that might shed light on the more suitable choice for you and your needs.
Budget is one of the primary defining considerations for many homeowners. Mini-splits can be up to 30% more costly per BTU of cooling power than central air conditioners. With that said, it’s also important to consider the installation costs and ductwork costs (if applicable) for your home.
Note: The cost of installing ductwork ranges based on multiple factors, including the size of your home, materials, etc. On average, ductwork installation ranges anywhere from $1,900 to $6,000, although the national average sits at about $4,000.
Considering the cost of a central AC unit itself can cost several thousand dollars, tacking on an additional $4,000 results in a costly investment. Sometimes, installing ductwork isn’t feasible. In that case, a mini-split may be the better option.
Another reason a mini-split system could be a good option for you is if you only need to cool one room. For example, you just need cooling in your living area during the day, and you sleep with your bedroom windows open to keep you cool. In this case, a mini-split would be less expensive than central AC.
However, keep in mind that cost is not only a major factor when selecting between mini-split vs. central air conditioning.
As you consider which option is better for your home, think about your comfort goals. Do you need every room cooled? Would you prefer independent control of the temperature in each room? Do you live in a milder climate or experience sweltering temperatures?
If you live in a mild climate or would prefer individual control of the temperature in each room, a mini-split might be a good option for you.
Note: Although zoning control is available with central air conditioners, it costs extra. Central AC zoning can help regulate temperatures in different parts of your house.
If you need great cooling in every room of your house or live in a scorching climate, you should consider a central air conditioning system.
Do You Want Heating Too?
If you live in a mild climate that experiences consistent temperatures throughout the entire year, heating and cooling capabilities may not be a necessity for your home. However, if you need heating and cooling capabilities, a central air conditioner can’t do both.
You could always get a matched furnace to pair with your central air conditioner, but it is a large expense on its own, often several thousand dollars.
Alternatively, you could opt for a mini-split heat pump instead of a central air conditioner. Why?
Central air conditioners cannot heat and cool, but a ductless mini-split heat pump can. This may be an aspect to consider if you need both heating and cooling capabilities in your home.
If you opt for a mini-split, you might have to consider some sort of air purification system. Mini-splits recycle the air already in the room it’s in and doesn’t have great filtration, which leads to poor indoor air quality.
With a central air conditioner, the air is well ventilated and filtered, as it pulls from fresh outdoor air and passes through a robust air filter. Some central air conditioners also have built-in advanced air purification systems, like UV lights.
Proper ventilation and purification can help remove and reduce airborne contaminants, including allergens, molds, and other toxins that can cause adverse health effects and discomfort.
Does Your Home Have Ductwork Already?
Ductwork is a major consideration when choosing between mini-splits and central air conditioners. If you don’t already have existing ductwork in your home, you’ll have to get it installed if you choose a central AC unit.
Not only is it expensive, but it is also a huge undertaking. The renovation is time-consuming and requires deconstruction and reconstruction of walls, which is messy and inconvenient.
If you already have ductwork, either option works easily enough without additional work.
How Large of an Area Do You Need to Cool?
Think about the size of the space you need to cool. How big are the rooms you need to cool? Are you cooling your entire home because your family is constantly in every room? Or do you need to focus your cooling efforts on a single room?
If you and your family occupy many rooms often, a central air conditioner may be a better option. Alternatively, you could install a mini-split in every room, although it may not be the most cost-effective solution.
Think about the size of the rooms you need to cool. If you’re leaning towards a mini-split in each room, remember that you’ll need enough BTUs for the square footage of every zone. Generally, you need between 20 and 30 BTUs of cooling output per square foot.
So, if you have a large room to cool with mini-splits, you might need more than one system in the same room. If you go with a central air conditioner, you must choose the tonnage size that matches your cooling needs in BTUs.
Central air conditioners can be noisy, so if noise levels are a major consideration for you, this is something to keep in mind. Most manufacturers have adopted sound dampening systems to mitigate noise to a comfortable level. However, they still generate noise, reverberating through the ductwork while the unit is on.
Mini-splits don’t use ducts, so noise levels are relatively low and whisper quiet. If noise levels could be a problem for you, consider a mini-split.
Air conditioners come with various EER/SEER ratings. These ratings determine the unit’s cooling efficiency, and the higher the rating, the more efficient the rating.
Generally, modern central air conditioners have SEER ratings of 13 or higher. The most efficient central air conditioners have a SEER rating of 28 (Lennox).
On the other hand, mini-splits offer some of the highest SEER ratings available. The most efficient mini-splits have SEER ratings up to 42 (Carrier).
Are You Okay with a Mini-Split Hanging on a Wall?
How do you feel about a mini-split unit suspended on the wall in each room of your home? Some folks find the looks of them entirely unappealing, thinking they throw off the room’s feng shui.
If you don’t appreciate the looks of a wall-mounted mini-split, you could go with a different mounting option, such as the floor-mount or concealed mini-split. However, these are usually much more expensive.
Or, if you don’t want to deal with a unit in every room, you might want to consider a central air conditioner. Of course, the indoor unit of a central AC system can be cumbersome, but people usually tuck it away in a basement or crawl space.
Also, the outdoor unit can disrupt your backyard’s aesthetic, but you can easily hide the unit with creative gardening or well-placed decor.
Choosing between mini-split vs. central air conditioning is a big decision. Both have advantages and disadvantages. Plus, there is no “one size fits all” solution.
Ultimately, the best option for your home falls to your needs and preferences. Every home is different, and picking the best option doesn’t have to be difficult, but it does require a little time and consideration!