Founder | BPI® Energy Auditor Certified Professional
Technical Editor | HVAC Tech at Kearns Heating and Air
If you’re in the market for a new heating and cooling system, chances are you’ve heard of mini-split heat pumps. These systems are becoming increasingly popular in residential homes.
Depending on your home setup and your heating and cooling needs, mini-splits can be a more efficient alternative to traditional HVAC systems.
They can provide both heating and cooling in a single system. Mini splits and other heat pumps use heat transfer, meaning they move ambient heat energy from one area to another by using the refrigeration cycle.
They are incredibly energy efficient since they don’t have to spend energy creating heat like most heating systems do. But just how well does heat transfer work when it gets cold outside?
Are mini-splits suitable for cold climates with extreme outdoor temperatures?
Are Mini-Splits Effective in Heating Mode?
In the past, mini-splits were only recommended for mild to moderate climates. In heating mode, the system must find ambient heat energy in the outdoor air to transfer inside the home.
When mini-splits were first introduced, the technology wasn’t as advanced as it is today.
Modern mini-splits have been created to heat in low climates. They are capable of providing heat even when temperatures drop to -15°F.
And if you regularly experience temperatures lower than that, you can get a mini-split model with backup heaters that will kick in when the heat pump can no longer draw enough heat from the air around it.
These systems are more expensive than mini-splits created for milder climates, so that is something to keep in mind.
If you do live in a cold climate, be sure to check the temperature range before deciding on which model to buy.
Advantages of Using Mini-Splits for Heating
High Energy Efficiency
One of the primary reasons to choose a mini-split is that it is more energy-efficient than other HVAC systems.
According to the US Department of Energy, mini-splits are up to 50% more efficient than traditional heating.
Because the mini split doesn’t need to create heat, it can save quite a bit of money on utility costs, despite being a fully electric system.
Often electric heat is the more expensive option, but that isn’t the case with heat pumps.
Mini-Splits Offer Zoning Capabilities
Your mini split can be connected to one or more indoor air handlers depending on your needs.
If you have more than one indoor unit, you have the option of zoning.
Zoning allows you to heat or cool specific rooms or areas in your home rather than the entire space.
This is a good way to save money or simply provide more comfortable spaces for occupants who are more sensitive to temperature changes.
You can set the air handler to maintain a comfortable temperature in their room without having to heat or cool the entire house.
Quiet and Discreet Operation
If you’re looking for a discreet heating system that won’t make much noise, mini-splits are an excellent option. Most indoor units are small and can be mounted on the wall or ceiling.
They have a small fan that circulates air but you can barely hear them operate unless you stand directly beneath the air handler.
Quick and Easy Installation
Most mini-splits are relatively easy to install and can be done within a day.
Their lack of ductwork makes them a good choice for homes that don’t have central HVAC systems or access to natural gas.
Cost-Effectiveness
Mini-splits are integrated with their own smart technology to maximize energy efficiency while maintaining your desired indoor air temperature.
They use less energy than most other HVAC systems and, thus, have lower utility bills.
Keep in mind that if you live in an extremely cold climate, the backup heaters will draw electric power and could get more expensive during cold snaps.
Apart from that, your heating and cooling costs will be lower than most comparable central HVAC systems.
Eco-Friendliness
If you’re concerned with your environmental impact but still want heating and cooling for your home, a mini-split is a great option. They use less energy and don’t emit harmful exhaust.
While they use refrigerant to transfer heat, the system is contained and should not leak into the atmosphere if it has been properly installed and maintained.
Disadvantages of Using Mini-Splits for Heating
Expensive Installation
As with most HVAC systems, mini-splits can have high upfront installation costs. You can expect these systems to last around 20 years if they are taken care of.
This means cleaning the filter every 6 weeks and having the system professionally serviced every couple of years.
The cost of your initial installation depends on the brand and model you choose, how many indoor air handlers you need and the HVAC company’s prices.
While some sources state that you can install these systems yourself, it’s not a good idea.
There are HVAC codes you are likely not aware of and you will likely void the unit’s warranty by not hiring a licensed company for the install. You could also damage your new mini-split if it is not installed correctly.
Only Some Models Are Suitable For Extreme Temperatures
As mentioned before, if you live in a cold climate, you will need a more expensive unit that has a lower operation range.
The cheaper mini splits are not suited for extreme cold and will not function in low temperatures.
Only Service Single Rooms and Small Areas
While you can get multiple indoor units for bedrooms, kitchens and living spaces, the ductless air handlers are not suited for heating bathrooms and closets.
If you live in a cold climate and need heat in your bathroom, you will have to get a ducted unit to provide heat for that space.
These are less common but they are available. However, they are more expensive and take more work to install.
Some Find Them Visually Unappealing
While most people find mini-splits unobtrusive, some consider them visually unappealing.
They do take up a bit of wall space where they are mounted. Most homeowners don’t have a problem with this but if you’ve seen photos of mini splits and you think they look ugly, they probably aren’t the system for you.
Determining What Size Heat Pump You Need
The size of the mini-split you need for heating is the square footage of the area multiplied by 25.
So, for example, if you have a 1,000-square-foot (92.903 square meters) space, you would need a 25,000 BTU unit.
The following table shows the recommended BTUs for various square footage.
| Room Size | BTUs Needed |
| 100 sq feet (9.2903 sq meters) | 2500 BTUs |
| 500 sq feet (46.4512 sq meters) | 12500 BTUs |
| 1000 sq feet (92.903 sq meters) | 25000 BTUs |
| 1200 sq feet (111.4836 sq meters) | 30,000 BTUs |
| 2400 sq feet (222.9673 sq meters) | 60,000 BTUs |
Your climate and home construction will also impact the size you need.
Pro Tip: If you’re unsure about the unit size you need, you can always consult an HVAC contractor. They can help you choose a suitable model for your home.
Final Thoughts
When used in the right situations, ductless heat pumps can be an effective and efficient way to heat your home. If you can handle the installation costs, they are a great way to lower your utility bills over time.
However, they aren’t suitable for every home so it is a good idea to talk with some local HVAC professionals before making a decision.