What is the most energy efficient mini split system SEER rating?
A 42 SEER mini split is currently the most efficient available, but probably not for long. Mini split heat pumps and ACs get more energy efficient every year – pushing the envelope for greater efficiency and energy savings.
Research Tip: The highest SEER mini split is a Carrier 42 SEER mini split. It uses technology developed by Midea’s Toshiba brand.
Highest SEER Mini Split
Mini split systems come in three types. Here they are along with the highest SEER mini split options in each.
1). Pro installation required: These units do not contain enough refrigerant to run effectively, so they must be installed by someone certified to buy and install refrigerant – in other words, only a licensed HVAC technician with a refrigerant card (certification) can install them. The lines are vacuumed, and a gauge is used to be sure the proper amount of refrigerant is added.
2). Semi DIY possible: These systems contain enough refrigerant, but to be properly installed, the lines must be vacuumed and connected to release the refrigerant into the lines. Homeowners sometimes do most of the installation and then hire a pro for vacuuming and connecting the lines. If you have an HVAC vacuum and gauge, and know how to use them, this can be a full DIY install since no additional refrigerant is required.
3). Full DIY: These mini split systems are fully charged with refrigerant – the lines included. They do not need to be vacuumed, and no gauge is required. The system is installed, and the sealed lines are connected, opening the seals, so that the refrigerant can flow through the system. It’s ready to go.
Highest SEER Full DIY Mini Splits
The most efficient DIY mini split – full DIY with no pro needed – is the MrCool E Star 3rd Generation heat pump system.
Among your options are 12,000 BTU 22 SEER mini split and 20 SEER mini split options at 18,000 and 23,000 BTU systems. Those are the most efficient DIY models from MrCool, though the brand offers several other options that are not as energy efficient.
The only other full DIY brand is Klimaire, and it makes a 12,000 BTU 20 SEER mini split and an 18,000 BTU 19 SEER mini split system plus other systems that are larger but not as efficient.
Highest SEER Semi DIY Mini Splits
Most semi DIY mini split systems are single zone units up to about 36,000 BTU depending on the manufacturer. You will find a few units up to 48,000 BTU. These systems have sufficient amounts of refrigerant in them, but they still need to have lines vacuumed prior to installation. That’s what makes them semi DIY mini splits.
Some DIYers install the system but hire a pro to handle the connection and vacuuming of the lines plus the release of the refrigerant from the condensing unit into the lines. The pro will also turn on the system and make sure it is functioning properly.
The highest SEER mini split options in single zone models are almost 23 SEER. These are available in 9,000 BTU options. If you need something larger, then you will find plenty of efficient single zone mini split systems in the 12,000 to 36,000 BTU. Efficiency range for these single zone systems is just under 17 SEER to 21 SEER.
Pioneer and Senville are the two most popular brands. Pioneer sizes are 9,000 to 48,000 BTU. Senville makes a more limited range from 9,000 to 36,000 BTU.
They make multizone systems too, but they’re more complicated to install, and most homeowners hire a pro for the work – but that doesn’t mean you can’t do some or all of the work if you understand the installation process and pay attention to details.
The most efficient unit from Pioneer is a triple zone aka multizone 22.5 SEER mini split system with 27,000 BTU capacity.
Senville mini splits are even more efficient – the most efficient being almost 24 SEER for cooling.
Highest SEER Pro-Installed Mini Splits
The Carrier 42 SEER mini split is the most energy efficient currently sold in the US, as noted above.
Research tip: As you’re researching and shopping for highest SEER mini splits, understand that all other brands not mentioned above require professional installation for their mini split heat pump and AC systems. Even some MrCool and Klimaire mini splits – the ones that are not DIY – need pro installation.
Your options for highest SEER pro-installed mini splits depend on the brand and on the size of the system.
Here are popular mini split efficiency levels and what brands make systems in that range:
*40 SEER mini split: Only the Carrier model mentioned above meets this high efficiency standard. But again, we expect that in the next few years, several other brands will begin making 40 SEER mini split systems.
*30 SEER mini split: Gree Sapphire is a 38 SEER mini split system, one of the most energy efficient ductless heat pumps available today. In fact, Gree makes several sizes of 30 SEER mini split or higher choices for your home or light commercial setting.
Mitsubishi FH Series has a 30 SEER mini split and 33 mini split system. This leading brand makes other 20-30 SEER mini split options in additional Mitsubishi ductless series.
*20 SEER mini split: All the major brands make systems with SEER ratings in the 20s.
For example, Daikin Quaternity heat pump offers up to 26 SEER; the 15,000 BTU model is a 21 SEER mini split. The LV Series heat pumps are up to 24.5 SEER efficient. And the Daikin Aurora ductwork heat pump is a 20 SEER mini split in single zone sizes from 9,000 to 15,000 BTUs. The multizone Aurora is a 21 SEER mini split.
The Fujitsu LMAS1, LUAS1 and RLFF/RLFH Series are 22 SEER mini split systems. LG LAU/LAN and Mitsubishi FH Series have 22 SEER mini split systems as part of their lineup.
LG Art Cool Premier mini split systems offer up to 27.5 SEER.
All these systems in the 20-30 SEER range make the 2023 Energy Star Most Efficient Central Air Conditioners list.
Should I Buy the Highest SEER Mini Split?
Not necessarily. High SEER mini splits in the 21 to 42 SEER range are pretty expensive compared to those with standard efficiency in the 16 to 20 range. Obviously, it is a general rule that the more efficient the system, the higher the cost. Yes, your monthly electric bill will be less with a high efficiency mini split. But will you recover the higher equipment cost by saving money on operating cost? Let’s consider that.
- Hot Zones: In a very hot climate, especially where you use air conditioning much of the year, then choosing a very efficient mini split makes sense.
- Cooler Zones: But where summers are shorter and/or not as hot, then buying the highest SEER mini split might not be worth the extra cost.
We recommend that the hotter and longer your cooling season is, the more efficient your mini split system should be. But check out our Comparison Calculator!
Do you want to compare SEER ratings and cost savings for your location?
This Mini Split SEER Savings calculator allows you to see the operating costs for mini split systems of various sizes and efficiency levels with the cost of electricity where you live!
To use the calculator:
1). Type in or use the arrows to input the BTUs of the system you have or are considering.
2). Use the Low SEER and High SEER sliding bars to choose the efficiency ratings of the less efficient and more efficient mini split. Grab the dots on the bars, and slide them left or right to the SEER you want for each.
3). Choose your state and the city nearest to you.
4). The average Annual or Yearly Cooling Hours will appear for your area. The data is supplied by the US Environmental Protection Agency.
5). Your current cost for electricity will also appear. The information is provided to Pick HVAC by the US Energy Information Agency.
Results: Annual Cooling Costs for the lower SEER and higher SEER units will shop up – plus the difference in the operating costs between them. The graph shows your potential savings over 1, 5, 10 and 15 years using today’s dollars.
The calculator allows you to quickly determine how much you will save with a more efficient mini split. Then, you can compare your cost savings to the upfront cost of the equipment – and for installation if you hire a professional. You’ll have all the information you need to make a smart decision in answer to the question: Should I buy the highest SEER mini split?
The Higher the BTU, The Lower SEER for Same Model/Series
The most efficient mini splits are usually small – up to 18,000 BTUs. The larger the unit (higher BTUs), the less efficient it is in any series..
Here are a couple of examples.
The Daikin LV mini split system is 20 to 24.5 SEER in efficiency. Here are the sizes and efficiency ratings:
- 9,000 BTU = 24.5 SEER
- 12,000 BTU = 23.0 SEER
- 15,000 BTU = 20.6 SEER
- 18,000 BTU = 20.3 SEER
- 21,400 BTU = 20.0 SEER
The Mitsubishi MUZ mini split ranges from 21.0 for the 18,000 BTU size to 33.1 SEER for the 9,000 BTU size.
There are exceptions! For example, the Daikin Aurora heat pump system is available in these sizes: 9,000 / 10,600 / 15,000 BTU. All of them are 20 SEER mini split heat pumps.
Did you know? The type of indoor unit often affects efficiency too. When you are researching a mini split system, compare the ratings when the different indoor units are considered – if there is more than one option.
Most Efficient Way to Run a Mini Split
Many HVAC technicians encourage you to “set it and forget it” when running a mini split system. Set the thermostat where you want it, and never change it. That’s their recommendation.
But is that the most efficient way to run a mini split?
Generally, a “set it and forget it” approach is a good strategy. A mini split system that runs continuously – without you shutting it on or off – will run the most efficiently. Turn it on, set the fan to Auto, and let it decide when it runs.
These additional tips will give you maximum efficiency and also premium indoor climate control and comfort.
Set the Thermostat to 76 or Higher
Obviously, a mini split set to 70 or 72 degrees Fahrenheit will run more – and cost more to run – than if you set it at 76F or 80F.
Do you think your home will be too hot at those temperatures? It probably won’t be at 76, but it might be at 80 degrees, but it’s a personal choice for what makes you comfortable.
Wear lighter clothing or even a damp handkerchief around your neck, and you’ll be more comfortable at a higher temperature.
Multizone Systems
If you have more than one zone, then you have the option of setting them to different temperatures. For example, if you have one zone that you really want a bit cooler, that’s fine. Set one to 74F or so and the other higher – but again, set them and forget them. And to do this, you’ll have to keep doors closed between zones, and that’s not always the best for overall system efficiency.
Keep it Clean and Maintained
This is essential! Clean the indoor unit and outdoor unit as suggested by the manufacturer. A dirty filter or coil will slow the transfer of heat – the unit is trying to move heat from inside to outdoors. If the process takes extra effort, the mini split will run longer and less efficiently.
Pro tip: You can gently clean the coils yourself between maintenance visits from your HVAC technician by following manufacturer guidelines. Video tutorials for cleaning the outdoor unit and indoor unit are available and should be carefully watched first.
And keep the outdoor unit free of debris like leaves and grass clippings because they reduce airflow and cause the unit to be less efficient.
Open Interior Doors
If all the zones are set to the same temperature, then keep doors open between zones/rooms.
This will allow the best circulation of air, and you’ll avoid “hot” rooms that way.
Install Insulating Blind on Sunny Windows – And Close Them
You can keep out heat with insulated blinds – but only if they are closed when sunlight is coming through those windows.
Add Weatherstripping Around Doors and Windows
If you have drafty window and door frames, install foam weatherstripping wherever you feel air moving. Stop those leaks, and warm air won’t flow in and make your mini split AC work harder and less efficiently.
Choose Energy Star Windows and Glass (and Doors too)
If you’re replacing your windows, choose efficient units like Pella 250 Series or Jeld-Wen Premium V-4500 vinyl windows. Those are just two of many Energy Star window choices.
To get the Energy Star rating, you might also need to select a glass option that is rated for your climate. For example, the Pella 250 Series windows come with standard low-E glass, NaturalSun low-E glass for chilly climates and SunDefense glass for sunny regions.
Triple pane glass is always an energy efficient choice too!
Things Not to Do
Don’t turn the temperature setting down during the day when it is hotter outside and up at night when it is cooler.
Don’t open windows in the cooler part of the day. While it might be OK for the temperature, especially if the air outdoors is cooler, it might allow a lot of humidity to enter. And humidity makes any air conditioner work harder. For example, in the AZ or New Mexico desert where air is really dry, an AC cools a room significantly faster than under similar temperature conditions in humid Georgia or Mississippi.
Don’t replace your windows only for the purpose of lowering energy costs. You won’t ever recoup the cost of windows through lower energy bills.
