In today’s world, where efficiency is king, people are constantly looking for ways to be more energy-efficient. This drive for efficiency led to the introduction of the mini-split ductless heat pump, which can produce both heating and cooling. However, because mini-splits were initially intended for climates with moderate winters, people often wonder if they’re suitable for heating in colder areas.
While heat pumps can produce hot and cold air, they tend to struggle on the heating side of things. They’re very effective under most conditions but lose efficiency when temperatures get too cold. However, they will still operate and produce heat for your home regardless of the ambient temperature.
Mini-split heat pumps are great appliances that have their place in the heating and cooling world. However, you should know what kind of performance to expect from your mini-split based on where you live. This article aims to guide and help you figure out if a mini-split ductless heat pump is right for you.
How do Mini Split Heat Pumps Produce Heat?
Mini-split heat pumps produce heat the same way that other heat pumps do. Rather than creating heat, a ductless heat pump takes heat from one place and transfers it somewhere else.
Mini-split systems consist of two units that work in conjunction to extract heat from the outside air. The outdoor unit is the condenser or compressor (depending on who you ask) and one or more indoor air handlers. The indoor air-handling unit is either ceiling or wall-mounted.
Here’s how the process works for a mini-split heat pump during winter.
- The heat pump extracts air from outside your home, regardless of how cold it is.
- The hot air gets transferred to the refrigerant in the heat pump’s outdoor unit.
- The refrigerant, which now contains hot air, is compressed, increasing the temperature.
- The hot refrigerant goes from the outdoor unit, through the refrigeration lines, to the indoor unit of the mini-split system.
- Air gets sucked into the indoor unit, passing over the now super-heated coils of hot refrigerant.
- Hot air is then blown out of the indoor unit with a fan motor and distributed into your home.
- This process is the same as when the mini-split is in cooling mode, except that instead of changing hot air to cold, it’s changing cold air to hot.
As you can see, the process of how a ductless heat pump works isn’t overly complicated. However, depending on how cold the outdoor temperature is, it gets harder and harder to extract enough warmth from the air. The colder it gets, the harder your mini-split heat pump will work during the winter months, and the more difficult it will have to produce warm air for your home.
How Efficient are Mini Splits for Heating?
Under normal circumstances, ductless mini-split heat pumps are highly efficient and save homeowners tons of money. They operate entirely on electricity, which is why they’re so efficient. However, that’s also why their energy costs go up during the winter months in cold climates. They aren’t powerful enough to keep up with extremely low temperatures in the way that a furnace or boiler is.
Mini-split heat pumps are between 25% and 50% more efficient than a furnace and air conditioner combo during typical use. The energy consumption of ductless mini-split heat pumps is even less than ducted heat pumps, which can have 30% or more of the conditioned air produced as it travels through the ducts.
The traditional heat pump advantages begin to wane in extremely cold climates. You can expect this efficiency to go out the window when the temperature drops below freezing. However, it’s important to note that your ductless heat pump will still work and keep your family from freezing. It just won’t be doing it efficiently.
All ductless mini-split heat pumps cool the same, but not all heat the same. Most can extract heat from outside air below freezing, but not all can extract heat from sub-zero temperatures.
Because mini-split heat pumps extract warm air and send it into your home, you might also notice a slight difference in the air temperature as it gets colder outside.
There isn’t a technical term for the difference in indoor air temperature. It simply doesn’t feel quite as warm as it usually would.
At What Temperature do Mini Splits Lose Efficiency?
The type of mini-split ductless heat pump you have will determine at what temperature it loses efficiency. Some mini-splits get designed to operate better at lower temperatures, while others thrive in intense heat. As a general rule, however, mini-splits start to lose efficiency when the temperature dips below 40 degrees Fahrenheit. While they will continue to produce heat for your home, they will do it less efficiently and less effectively.
Do Mini-Splits Stop Working at a Certain Temperature?
Certain ductless mini-split heat pumps have a safety measure built into the system where they stop working at a set temperature. The typical stopping temperature for these mini-split heat pumps is 5 degrees Fahrenheit or 115 degrees Fahrenheit. You should check with your specific heat pump provider before installing one to determine if it has this built-in feature.
This safety feature is to protect the heat pump from getting overworked. Not all ductless mini-split heat pumps are heavy-duty enough to operate under intense conditions. If you live in a cold climate, the last thing you want is for your heating source to give out when the ambient temperature gets too cold.
Mini Split Temperature Ranges
To help you decide about the type of heat pump you need, here’s a table showing different temperature variations from different mini-split distributors.
|Mini-Split Brand||Heating Mode||Cooling Mode|
|Senville (Aura)||-22 deg. F – 86 deg. F||-22 deg. F – 122 deg. F|
|Daikin (Aurora)||-13 deg. F – 60 deg. F||14 deg. F – 114 deg. F|
|Fujitsu||-5 deg. F – 75 deg. F||14 deg. F – 114 deg. F|
|Pioneer (Arctic)||-5 deg. F – 86 deg. F||5 deg. F – 122 deg. F|
|Senville, Pioneer, Mr. Cool||5 deg. F – 86 deg. F||32 deg. F – 122 deg. F|
|Daikin||5 deg. F – 75 deg. F||50 deg. F – 115 deg. F|
|Mitsubishi||-13 deg. F – 80 deg. F||32 deg. F – 115 deg. F|
As you can see, the brand and type of mini-split you choose will make a big difference in how well it does during the winter months. Another thing to keep in mind is that each mini-split producer has many different models with their production line. You should ask if a particular model will operate better in cold conditions than other models.
How to Make Your Mini Split More Effective for Heating Purposes
Regardless of what type of mini-split heat pump you have, there are ways that you can increase its performance during the winter months. While having it professionally inspected and maintained is crucial, there are plenty of things you can do on your own that could save you money and make your mini-split more efficient.
Get a Mini Split That’s the Right Size
Like regular air conditioners and furnace combos, mini-split heat pumps have many different size variations. This is because different heat pump sizes can produce different amounts of hot and cold air. You must have a professional HVAC technician size and install your mini-split. Heat pumps that are too small will get overworked and won’t be able to keep up during the cold winter months.
Ensure Your Home is Properly Insulated
Proper insulation applies to heat pumps and other forms of heating and cooling. Your mini-split will quickly get overworked if all the hot air it’s creating leaks out of your home because of bad insulation.
Protect the Outdoor Compressor from Snow
Another good way to increase the efficiency of your mini-split is to build a small roof over the top of it to protect it from the winter snow. Snow that falls onto the mini-split’s outdoor compressor (aka condenser) could get into the evaporator coils and cause them to freeze up. It would be best to put your mini-split on a ledge or bracket to keep it at least two feet off the ground.
Give the Outdoor Condenser Room to Breathe
Your mini-split works by sucking air into itself and warming it up. If it doesn’t have room to breathe, it won’t be able to absorb enough air to transfer into heat. Ensure that you don’t have bushes or structures too close to your outdoor unit that could impede its suction abilities.
Make Sure Your Refrigeration Lines are Long Enough
If you had a heating and cooling professional install your heat pump, you won’t have to worry about this. However, if you do it yourself, make sure that the refrigeration lines connecting the indoor unit to the outdoor one are at least 15 feet long.
Keep Your Air Filters Clean
You have to protect your outdoor unit for top efficiency during the winter months, but you also have to protect your indoor unit. Make sure that the air filter inside the indoor unit is clean so that it can suck enough air back into the unit to redistribute into your home.
Ensure the Outdoor Unit can Drain
Your outdoor unit has a drain pan on its bottom. The outdoor unit will create condensation that drips into the drain pan and out the bottom as it’s operating. However, you may have to make additional holes in the drain pan to ensure enough drainage capabilities. Otherwise, water will build up in the pan and eventually freeze. Freezing water can also cause your evaporator coils and fan to freeze up and become expensive repair jobs.
Unfortunately, while these measures will help your heat pump work better in cold conditions, they will only go so far. It’s vital that you have your mini-split system professionally installed and serviced annually and that it’s the right size and type of heat pump for your home.
Best Mini Split Heat Pump for Cold Weather
While many different mini-split heat pumps advertise that they do well in winter conditions, certain brands perform better than others. If you live in an area where the temperature is consistently in the teens, single digits, and below zero, we recommend the top mini-split systems.
- Samsung Smart Whisperer Max Heat
- Mitsubishi Electric MSZ-FS Mini Split Heat Pump
- Daikin Aurora 9,000 BTU 20 SEER Air Conditioner Heat Pump
- PIONEER WYS009AMFI22RL 9,000 BTU Heat Pump
Do I Need a Backup Heat Source for My Ductless Mini Split System?
You should install one if you have your heart set on a mini-split heat pump system. However, depending on where you live, you may require a source of backup or supplemental heat if your mini-split cannot keep up.
Ductless mini-split heat pump systems as a primary heat source are perfectly fine in most climates. A backup heat source is especially important for northern areas like Maine, Alaska, Montana, and similar states where weather temperatures can dip below freezing for several days or weeks.
Mini-splits often get combined with a boiler system in cold areas. The mini-split can provide heat down to a certain temperature before losing efficiency or operating ability. Your boiler system kicks in and keeps you and your family from freezing when that happens. Outside of boilers, you can pair a mini-split heat pump with a traditional furnace, a wood-burning stove, or any other heat you can think of.
Best States and Regions for Mini Split Heat Pumps
The best states to use your mini-split heat pump as the sole heating and cooling source go as follows.
- New Mexico
- Nevada (except in the mountain regions)
- South Carolina
- Mini-splits can be the sole source of heat for many states in the middle of the country, aside from mountainous regions and certain areas.
Do Mini-Splits Freeze During the Winter?
While it has to be very cold outside for a very long period, a mini-split heat pump can freeze during the winter. The possibility of freezing is especially true for heat mini-splits that aren’t rated for low temperatures.
The heat exchanger in the outdoor unit can freeze up and cause a stop in operations. However, mini-splits have a built-in defrosting feature to unfreeze the heat exchanger and get things working again. This process typically takes around 10 minutes.
How Much Does it Cost to Heat with a Mini-Split?
The total cost of heating with a mini-split depends on several factors. The type of system you have, the temperatures it’s operating in, and the size of your home will all play a factor. On average, mini-splits cost between $30 and $70 to operate in moderate climates and between $125 and $300 in colder climates.
Are Mini-Splits More Efficient at Heating or Cooling?
While mini-splits are capable of heating and cooling, they tend to be more efficient on the cooling side. They’re more effective at drawing cool out of the warm summer air than drawing heat out of the cold winter air.
Are Mini-Splits Better than Central Heating?
Mini-splits are better than electric central heating. Electric central heating is not efficient and can drive your utility bills higher. Electric central heating uses electric heat strips that use one unit of energy for every one unit of heat produced.
Gas central heating is more efficient than electric central heating and will provide more warmth faster than ductless systems. However, you can expect energy losses of 30% or more through duct losses in unconditioned space with any central ducted system. This waste can add up over time.
The right mini-split system can be better for a small to medium-sized space than both electric or gas central heating.
Are Mini-Splits Better than Space Heaters?
Mini-split systems are safer than space heaters. Space heaters can be electric, propane, natural gas, kerosene, etc. Space heaters are often portable and sit on the floor, which can cause someone to fall or burn a child. Propane or gas space heaters that are permanently installed are safer but still present burning hazards.
Mini-splits don’t pose burning hazards and are installed close to the ceiling and not on the floor. They are also more energy-efficient, and some models heat well even with outdoor temperatures below zero.
As you can see, mini-splits are great heating and cooling appliances, but only when they get used appropriately. Attempting to heat your New York or Wyoming home with a mini-split during a harsh winter won’t go very well for you.
You must choose the right heat pump for your climate and invest in a backup heat source when necessary. Failing to do so will result in a less efficient mini-split, but it could also put you and your family at risk.