Ductless Mini-Split Heat Pump Guide

Looking to improve your home’s comfort and efficiency? Want to eliminate hot or cold spots that your old HVAC system can’t seem to heat and cool evenly? 

Ductless, mini-split heat pumps offer a flexible, highly efficient solution for heating and cooling your space. Whether you're electrifying your home or simply looking for a smarter way to manage your comfort, read on to understand how these systems work, explore their unique benefits, and determine if they're the right fit for your needs.

What is a mini-split heat pump?

A mini-split heat pump, also known as a ductless heat pump, is a smaller version of a standard central heat pump with one key difference. Both use indoor and outdoor units to move heat in or out of a home. However, where they heat and cool within the home is different.

Central heat pump: Heats or cools air in one central place (like a basement or attic), then sends the conditioned air throughout the house via ducts.

Mini-split heat pump: Heats or cools the air via interior units throughout the house. No ducts needed.

Indoor mini-split units are mounted on walls or ceilings. You can install as many indoor units as you need, though they may require additional outdoor units.

Each unit can be separately controlled and programmed, which can improve energy efficiency in many cases. 

How do mini-splits work?

Heat pumps work like two way air conditioners. A refrigerant line moves heat into or out of a house.

A mini-split has refrigerant lines running between an outdoor unit to one or more indoor units. The room’s air is heated or cooled at each indoor unit, meaning you can install a ductless system in a building with no previous ductwork.

Eliminating ducts is an energy saver on its own. Energy Star estimates 30% of a central HVAC system’s energy usage can be wasted when conditioned air travels through ducts.

Mini-splits are also very energy-efficient heating options. They move heat from the outside air rather than consuming fuel to make heat, as a furnace — electric, gas, heating oil, or propane — does. This is a much more efficient process than other in-room options, like electric baseboard heaters, and it has the same no-duct advantages over central options.

An Energy Star-certified mini-split can deliver up to three times more heat energy than the electric energy it uses. Compared to standard electric heating, Energy Star-certified mini-split heating can reduce energy usage by up to 60%.

Zoned heating and cooling with mini-splits

Another advantage to mini-splits is the possibility for zoned heating and cooling control in your home. 

Mini-split systems can work with up to five indoor units per outdoor unit, depending on the model. That allows you to heat or cool rooms as you use them and not when they’re sitting empty. That can cut your energy use.

Advantages of mini-split heat pumps

Potential advantages of switching to ductless, mini-split heating and cooling for your home include cost savings, energy efficiency, comfort, and fewer maintenance requirements.

Cost savings

Mini-split heating and cooling systems may save you money by being efficient in a couple of ways.

• No heated or cooled air is lost while traveling through ducts.
• Heat pump technology is more efficient. A heat pump can cut energy cost by 75% compared to an electric furnace or electric baseboard heat, according to the US Department of Energy.

Cost savings aren’t guaranteed and depend on the following and more.

• The system being replaced
• The size and layout of the house
• The local climate
• Relevant gas and electric rates
• Any available incentives

Energy efficiency

Energy Star-certified mini-splits may be up to 30% more efficient than ducted central air systems and up to 60% more efficient than electric furnaces. 

Some modern mini-splits regulate energy usage with variable speed technology and maintain a steady temperature instead of cycling on and off to meet a thermostat’s setting. Many mini-split systems are compatible with smart devices and have smart, programmable features like seven-day scheduling, sleep mode, and target temperature and humidity ranges, improving energy efficiency. 

Reliable performance

The old knock on heat pumps — that they fail to keep up with really cold temperatures — is fast becoming a thing of the past.

Cold climate heat pumps can perform well even in freezing temperatures. And, instead of the all or nothing nature of a central furnace, variable speed heat pumps can keep your home at a steadier temperature.

Disadvantages of mini-split heat pumps

Here are some of the potential disadvantages of mini-split heat pumps. 

Initial cost

Like with any home improvement project, costs vary. While ductless mini-splits can be more affordable than installing central HVAC and new ductwork in a new build, they can become cost-prohibitive for large homes. Additionally, switching from gas, oil, or propane to an electric system increases upfront expenses. 

Online estimates vary, but single zone mini-splits can start at around $8,000 to $12,000 with additional cost for additional zones.

Heat pump leasing replaces the upfront cost with predictable monthly payments. Leases typically include maintenance and flexible end-of-term options. To learn more about leasing a heat pump or other HVAC system, check out the Palmetto Comfort Plan.

Aesthetics

This potential disadvantage is clearly in the eye of the beholder, but some people might find indoor units to be sore thumbs to a few rooms in their home. Units can be mounted on walls, ceilings, or floors where there is enough space and proper airflow.

Increasingly, heat pumps that take aesthetics into account are arriving on the market.

Mini-split maintenance

The most important maintenance step a homeowner can take is cleaning filters and changing them as recommended. Some units have a standard mesh filter that should be wiped and cleaned every week or two. Some units have replaceable filters that should be changed every 1-3 months or as recommended by the manufacturer. 

A professional should deep clean mini-split exterior and interior units every 1-3 years, depending on the environmental conditions around your home and your usage, according to the Department of Energy.

Are mini-splits the best heating and cooling option?

Mini-split heat pumps can be a good fit for any home depending on the situation. Mini-splits are especially good options in the following situations.

• New builds
• Homes without existing ductwork
• New home additions
• Newly finished basements or attics
• Homes that would benefit from efficient zoned heating and cooling

If you’re switching to electric appliances and electrifying throughout your home, electrifying your heating and cooling with mini-splits may be your best option.

In some cases, the cost to install an adequate mini-split system would be more than the benefits you’d get from switching to a ductless system.

Can you install a mini-split heat pump by yourself?

It’s possible, but not recommended, to install a mini-split system yourself. While you could save money if all goes according to plan, the risks and potential major expenses or future issues outweigh the potential benefits of a DIY mini-split installation. 

An amateur installation carries the risk of accident, injury to yourself or others, electric shock, fire hazards, and damage to your home. An improperly installed heat pump can be less efficient, need more frequent repair, and have a shorter life.

Mini-split heat pumps designed for easier DIY installation do exist.

Mini-split shopping advice

If you’re ready to make a purchase, you want to weigh factors such as the energy efficiency ratings of different systems. Look at the SEER (seasonal energy efficiency ratio) rating, the HSPF (heating seasonal performance factor) rating, efficiency and estimated cost information on an EnergyGuide label, and for Energy Star certification. 

You want a system designed for the size and layout of your space, how you expect to heat and cool it, and your area’s climate. If you plan on connecting your new system to smart home devices, ensure they will be compatible.

Consider home solar panels that can power your heat pump with solar power right from your roof. Explore your HVAC options with Palmetto.

Frequently asked questions

Do you need a mini-split for every room?

No, one of the positives of mini-split heat pumps is you can customize the system to fit your home and lifestyle. 

What is the life expectancy of a mini-split system? 

Mini-split systems can last 20 years or longer. Proper installation and maintenance will generally improve a system’s performance and lengthen its lifespan. 

Disclaimer: This content is for educational purposes only. Palmetto does not provide tax, legal, or accounting advice. Please consult your own tax, legal, and accounting advisors.