What is a Ductless Heat Pump?
A ductless heat pump is an efficient and convenient way for homeowners who don’t have ductwork to heat and cool their home. Unlike central air conditioning systems, which feed air through a system of ducts and vents, ductless systems are installed directly in the room they’re intended to heat or cool.
The smallest and most basic ductless heat pumps are also known as mini-split heat pumps and include just one indoor unit and one outdoor unit. But, you can still install up to five indoor units to form a multi-split system. This means you can heat or cool up to five spaces without ducts, making a ductless heat pump an easy and flexible solution to indoor temperature control.
How does a ductless heat pump work?
Understanding how a heat pump works is the key to understanding how a ductless heat pump works. Heat pumps perform both heating and cooling functions, depending on the weather outside and your temperature needs. When it’s cold out, a heat pump can extract heat from the ground or air outside and transfer it into your home. When it’s warm out, a heat pump can reverse its mechanisms with a reversing (or switchover) valve that redirects the flow of refrigerant. Then, the heat pump can pivot to a cooling function by removing heat from the home and sending it outside.
Ductless heat pumps manage their heating and cooling functions with a heat transfer cycle between the outdoor and indoor units, connected together by a pipe. These systems also rely on refrigerant, a chemical cooling compound, to absorb and release heat, as well as carry heat between the indoor and outdoor units.
How a ductless heat pump cools
- The cooling process begins when heat from inside your home is extracted and put into the ductless heat pump.
- This heat is blown over the indoor coil. The refrigerant inside the indoor coil absorbs the heat from your home and continues on.
- The refrigerant travels through the pipe from the indoor unit to the outdoor unit. Here, it enters the compressor, which heats up the refrigerant even more so it’s hotter than the air outside.
- Finally, the extremely hot refrigerant enters the outdoor coil, where the heat drawn from your home is released outside. The cooling process repeats.
How a ductless heat pump heats
Like we mentioned earlier, when a ductless heat pump switches from cooling to heating or vice versa, the reversing valve redirects the flow of refrigerant. The system knows to do this on its own based on the temperature you set, so you’ll never need to touch the reversing valve. Once the ductless heat pump is ready to heat, these are the steps it follows:
- The heating process begins when heat from outside is extracted and put into the ductless heat pump.
- The heat is blown over the outdoor coil. The refrigerant inside the outdoor coil absorbs the heat from outside and continues on.
- The refrigerant travels to the compressor, where more heat is added
- Finally, the now-hot refrigerant travels through the pipe into the indoor unit, where it enters the indoor coil. Here, the heat from the outside is released into your home. The heating process repeats.
Types of ductless heat pumps
There are two main types of ductless heat pumps: mini-splits and multi-splits. While all ductless heat pumps only have one outdoor unit, there can be up to five indoor units connected to a singular outdoor unit. When the ductless outdoor to indoor ratio is 1:1, it’s called a mini-split. When the ratio is any more than 1:1, it’s referred to as a multi-split.
Plus, ductless heat pumps can be mounted to either the wall or the floor inside, making it easy for homeowners to place the ductless system exactly where they want in their home.
Is ductless heating right for your home?
A ductless heat pump isn’t right for everyone, but there are certain circumstances that make ductless heating a viable option. If any of the following seems to apply to you, you might want to consider investing in ductless heating and cooling:
- Your home (or space you want to heat) doesn’t have ductwork already installed.
- You only want to cool or heat one section of your home (like an attic, garage, sunroom, home addition etc.), not the entire thing.
- You want to invest in an energy-efficient method of heating and cooling.
- You’ve recently added an addition to your home and need temperature control within it.
- Your home has a room or section that always seems to be too hot or too cold.
- You have multiple people with different temperature needs living in your home.
How to choose a ductless heat pump
If you’ve decided that a ductless heat pump is the right choice for your space, the next decision you’ll face is what kind you should have installed. While this comes down to personal preference, a good rule of thumb is that when only one space needs heating and cooling attention, a ductless mini-split should be installed. When multiple spaces need heating and cooling, or if your home has multiple people with different temperature needs living in it, ductless multi-splits are the best option. That way, you can receive heated and cooled air throughout your home while tailoring each space to your specific temperature needs.
Ductless heat pump cost and lifespan
The cost of a ductless heat pump depends largely on how many units you’re getting installed in your home. Like we’ve said before, ductless heat pumps come in mini-splits and multi-splits, with the potential to have up to six units in a multi-split (five inside and one outside). According to Home Advisor research, it costs on average between $700 to $2,200 to install a basic mini-split. As you get into multi-splits, the average ductless heat pump installation cost can be anywhere from $2,000 to $13,000, depending on the number of units being installed. Cost will also increase anywhere from $200 to $500 more if your home doesn’t have a concrete pad for the outdoor unit to sit on, or if the HVAC technician needs to install or replace an electrical circuit.
While these costs may seem high, scheduling regular ductless system maintenance with an HVAC professional will help keep your system running efficiently and could help increase its lifespan, so you don’t have to spend money on a replacement system for a long time after the initial installation. The average lifespan for a ductless heat pump can be anywhere from 15 to 30 years depending on the type, maintenance practices, location, and amount of use.
Pros and cons of a ductless heat pump
Investing in a ductless system comes with both advantages and disadvantages.
One of the biggest advantages of ductless heat pumps is that they are incredibly flexible. Remember, a multi-split ductless system means you can heat or cool up to five separate rooms or spaces in your home. Plus, each indoor unit can connect to its own thermostat, so you can set your ideal temperature in each space. These features make ductless heat pumps flexible heating and cooling systems that you can tailor to your own individual needs.
True to its name, ductless heat pumps do not require any ductwork to heat and cool your home. For homes that do have ductwork, poorly sealed or poorly insulated ducts that leak heated air into unheated spaces can cost homeowners hundreds of dollars every year on their energy bills, according to Energy.gov. With a ductless system, you don’t have to worry about the energy loss associated with worn down or poorly maintained ducts, which means you may be able to save on your monthly energy bill.
Pro: Easy to install
We’ll get more into what to expect when it comes to ductless heat pump installation later, but for now just know that another pro of this system is its easy installation process. Only a small, 3-inch hole is required to connect the indoor and outdoor units of a ductless system, and most HVAC technicians have access to varying lengths of connecting wires. This means, after an HVAC professional makes the hole, they can connect an indoor and outdoor unit anywhere from 1 foot to 50 feet away from each other.
Central air conditioning systems can typically be hidden away or kept out of sight — outside, up in the attic, down in the basement. With ductless heating and cooling systems, the indoor unit must be installed directly in the home because the system doesn’t rely on ductwork to carry air. Some homeowners don’t like the appearance of HVAC units throughout their home and would rather they be tucked away, although it completely depends on personal preference if this is an issue for you.
Con: Installation Cost
Despite the easy installation process, ductless heat pumps can be pricey to install. While a ductless mini-split heat pump that requires just one indoor and one outdoor unit won’t be too expensive, as you take on multi-split installation, costs begin to rise. Multi-split ductless systems can have up to six individual units involved so the more indoor units you choose to install, the more it will cost in installation fees. This means, it might be more expensive to install multiple ductless units than it is to install ductwork into a new home. Plus, any amount of ductless units are typically more expensive to install than window units.
Sizing issues can happen with any HVAC unit but it’s particularly important to mention when it comes to ductless systems. If your system is sized incorrectly and you wind up with a ductless system that’s too big or small, you can face short cycling, which means heating and cooling won’t be done quickly or efficiently. Short cycling costs you time and money in getting your home to your desired temperature.
Ductless heat pump installation: What to expect
Ductless heat pump installation must be completed by a licensed HVAC technician, but when a technician does come to your home it’s always good to know what to expect. Ductless heat pump installation takes on average about five hours, but varies depending on how many units the technician needs to install. One of the best parts about ductless heat pumps is that they’re installed directly into the rooms where you want them, so you won’t need to make major alterations before installation.
Before your technician arrives, be sure to move furniture and form a clear path for your technician in each room where you’d like a ductless system installed. When your technician starts the job, they’ll typically install the outdoor unit first, then drill small holes in the wall of each room where the indoor units will be installed. The technician will then install the indoor units and connect them to the outdoor units with pipes. If necessary, the technician can install thermostats in each room where a ductless unit has been installed for easy and convenient temperature control. Once that’s done, you’ll be all set to use your ductless system.