What is a Ductless Mini Split Air Conditioner?
A ductless air conditioner system (also known as a mini split AC unit) works by having a condenser outside of your home that pumps heat in and out and cools with refrigerant through copper lines that lead to an indoor air handler unit that distributes the cool air with a fan. They are able to cool and heat your home efficiently. However, if you live in an area with very cold temperatures ductless AC installation may not be your best HVAC installation option.
Ductless air conditioners are only capable of providing heat in temperatures as low as -15 degrees Fahrenheit, but most models will tap out when temperatures drop below 5 degrees Fahrenheit. You can always pair your ductless mini split system with a new furnace if you need more heating capacity during the colder months.
Ductless Air Conditioner Installation
A certified AC installer is required to install a ductless air conditioning system who can ensure lines, cable, valve, and drainage are installed correctly and functioning properly.
But before finding a reliable installer, let us understand how these installations actually work. This will help you understand the process and assess how knowledgeable your contractor is.
Ductless Split AC system
- The split system has three main parts. The compressor which is located outside, the inside air outlet (air handler) and a remote control.
- The compressor and the inside air outlet can be placed up to 50 feet apart and still function properly.
- Additional materials used for installation include copper tubing that connects the outside and inside unit. The tubing carries the necessary refrigerant to operate the system.
- A plumbing connection is also necessary to drain the condensation accumulated by the system. A line can be piped into an indirect drain in the home such as the one used for a washing machine or a dedicated drain may be used to redirect the condensate.
Multi-split Ductless AC system
- The multi-split uses the same equipment as the split system with the exception of having only one air outlet. Multi systems can have up to five air outlets.
- It takes more copper tubing and wiring for the multi-split system since each air outlet is connected independently to the compressor.
What Size Mini Split AC Unit Do I Need?
Depending on the size of your home or the rooms that require heating and cooling, you will want to install a ductless mini split unit that has the BTU capability to efficiently handle your home’s temperature. For cooling or heating a 400 square foot area you will need a mini split unit able to produce 9,000 BTU’s. You can see our full chart for room size and cooling capabilities below.
Ductless Heat Pump Size Needed
|Ductless Heat Pump BTUs Needed||Room Square Ft.|
|6,000 BTUs||150 to 250 sf.|
|7,000 BTUs||250 to 300 sf.|
|8,000 BTUs||300 to 350 sf.|
|9,000 BTUs||350 to 400 sf.|
|10,000 BTUs||400 to 450 sf.|
|12,000 BTUs||450 to 550 sf.|
|14,000 BTUs||550 to 700 sf.|
|18,000 BTUs||700 to 1,000 sf.|
|21,000 BTUs||1,000 to 1,200 sf.|
|23,000 BTUs||1,200 to 1,400 sf.|
|24,000 BTUs||1,500 sf. +|
Mini Split vs. Multi Split AC
Mini split air conditioners and multi split AC are exactly the same units utilizing a heat pump to push heat in and out and refrigerant to cool the air being pushed through. However, with mini split AC units the air handlers inside regulating the pushed air’s temperature will all push the same cooled air and only one thermostat to control each room with the same temperature output. If you install a multi-split air handler then you will be able to have different temperature settings in each room that has a ductless wall unit installed. If you are considering a full HVAC system replacement you’ll want to decide if the costs of a new AC unit and furnace are worth the investment in comparison.
Single Zone vs Multi Zone Installation
The number of zones your home will need depends on its layout, size, the amount of daily use, and your budget. As discussed there are the two types of ductless systems. The first is a mini split ductless air conditioner system, which consists of one compressor and one air conditioner outlet, and is meant for cooling your home with one set temperature. On the other hand, a multi-split zone air conditioner system has one outdoor HVAC unit that connects to as many as five indoor ductless air units, often mounted on interior walls and can keep different temperatures for each independent room and unit combo.
Difference Between Ductless AC and Central AC
The main difference between ductless mini split AC units and central air conditioning systems is the way treated air is distributed throughout the home. Ductless AC systems require a few inches of slim cable wiring running through for cool air to travel through. Whereas, central AC systems require ducts or vents for cool air to travel through.
If you already have ducts or vents in place a central AC system would be inexpensive comparatively. But, because the air has to travel through ducts before it’s cooled, some of the air is lost in the unconditioned areas of your home. This results in a less efficient system overall, which can result in higher utility bills.
Central AC unit installation costs are usually more expensive than ductless installation. However, if your home is larger than 2500 square feet, ductless systems will not be an effective system for you. In that case, choosing a central AC unit will be better option for you in fulfilling your heating and cooling needs in the long run. Central air conditioning can also stand up to much colder temperatures compared to ductless mini systems.
Is Ductless Mini-Split AC Cheaper than Central AC?
Yes, a major benefit of ductless AC is the cost savings. A great deal of thermal energy is lost through the ducts in a home’s central HVAC system. When cooling your house with ducts, the cool air will be warmed by the hotter air outside the ducts as it moves around your home.
Even ducts that are heavily insulated will let some of that cooled air escape into the surrounding space. That means that with a central AC unit, a great deal of cooled air is lost to exterior walls and other non-essential areas of the house.
Ductless AC units, on the other hand, deliver heat right where it’s needed. No cool air is lost with ductless air conditioning because there are no ducts to worry about—instead, the system kicks on and heat floods into the space right away.
Unlike a conventional HVAC system that uses one thermostat to control temperature for the whole house, each unit in a ductless system has its own thermostat. This allows unique temperature settings in each room that has a ductless AC unit, which translates to greater efficiency and often reduced utility bills.
- Since there’s no ductwork, installation costs are generally lower than central HVAC systems.
- Installation is generally less disruptive to your existing home because it doesn’t require the same physical space as ducts.
- Ductless split systems offer flexibility when installing indoor air outlets as they can mount against the wall, flush against the ceiling, or recessed into the ceiling.
- Ductless multi-split air conditioning system outlets are designed to blend in with the décor with a variety of colors and styles available.
- Multi-zone systems also have the advantage of using two to five air outlets allowing an individual air outlet to be placed in multiple rooms. Each air outlet comes with its own thermostat for individual room control.
- Ductless systems allow you to reclaim closet space or even have higher ceilings since you don’t need to leave room for ducts.
Choosing a Ductless Air Conditioner
Look out for these energy rating parameters while selecting your ductless mini or multi split air conditioner. It will help you save up on utility bills.
Energy Star Rating
EER and SEER
Check for a high Energy Efficiency Rating (EER) and Seasonal Energy Efficiency Rating (SEER). A higher rating will increase the cost of the ductless AC system, but will pay for itself in time, since the unit will cost less to operate.
When you’re shopping for units, you’ll notice mention of BTUs. It stands for British Thermal Units, a unit of power. The bigger your room, the more BTUs you need to keep it cool.
Use an online BTU calculator or chart to estimate your needs based on the square footage of each room. For example, a 150-square foot room needs up to 5000 BTUs. A 500-square foot room needs 10,000 BTUs, and a 1,960-square foot room needs 28,500 BTUs.
For informational purposes, a 22,000 BTU 2-ton ductless mini-split system runs on 230 volts; it has a high SEER of 15, which results in quality energy efficiency, and it can cover up to 1500 square feet.
Ductless AC Labor Costs
Comfort and energy efficiency are the biggest advantages of mini-split systems. But if your ductless system is installed incorrectly or if it is not the right size, you will not experience either of those benefits.
Unless you are a builder or remodeler, it is worth hiring a ductless air conditioner installer with the right tools in their belt. The contractor has to lay concrete for the outdoor unit, cut a hole in the exterior wall, run the electrical lines for the conduit, and perform other tasks as needed, such as getting rid of some of your current system’s components. You can expect to pay between $1300 and $2000 for these components.
While you may be tempted to settle for the best price regardless of specific experience, remember that ductless heating and cooling systems are still a niche market in the U.S. You may have to hunt a little for the right contractor, so don’t settle for someone you are not sure will do a good job just because they offer the best price on labor and installation costs.
Other Things to Consider
- If you live somewhere with extreme summer temperatures, a ductless air conditioner may not be able to bear the entire burden of cooling your home on the hottest days. You may want to hold onto your traditional HVAC system to use as a supplement when needed.
- If you have wall units or radiant heating, you can integrate just one ductless system to take care of your main living area or “zone,” rather than switching to ductless in your whole house.
- There may be rebates and tax incentives available to you, so check them out before you red or green-light this project.
Finding a Mini Split AC Installer
Protect Your Investment. Contact a licensed mini split AC contractor near you to assess your usage and to size your ductless mini split system appropriately and according to your home’s layout.
Before hiring an HVAC contractor, ask for a written estimate and copies of their HVAC license and insurance coverage. Since most municipalities require HVAC contractors to carry a valid heating and air conditioning license as well as liability and worker’s compensation insurance, you would be wise to verify their credentials before signing on the dotted line.
Check with your local building department or attorney general’s office to verify their contractor license. Contact the applicable insurance companies to verify they hold the required insurance coverage.
Visit the BBB or Better Business Bureau website to search for recent complaints or legal action against said contractor or company.
Ductless HVAC Maintenance
Whether you choose a split or a multi-split ductless system, each ductless air conditioner will require a few steps to keep both components running in peak condition for its estimated 12 to 15 year lifespan:
- Regularly clean and replace the filter: This allows the system to keep the air purified and will help prevent system breakdowns. To maintain optimal airflow to the compressor, you’ll need to keep plants, tall grass, and debris away from the unit.
- Schedule an annual checkup with a licensed professional to ensure all parts are functioning at full capacity. A licensed professional will:
- Clean or replace the filter
- Clean the compressor and remove any build-up from the condenser coils
- Check that the fan and valve function properly
- Inspect the copper tubing to ensure the refrigerant isn’t leaking
- Make additional repairs or replacement as needed
- Inspect electrical connections to ensure there are no loose, frayed, or faulty wires