Are ductless mini-splits more efficient?
Is a ductless mini-split right for your home? With the rising cost of electricity, many homeowners are looking for ways to cut back on their home’s energy use. Upgrading your HVAC system from a forced-air setup to a ductless one might be the answer.
In this article, we’ll review what makes ductless mini-splits more efficient, as well as a few factors you should consider when upgrading to a ductless setup. With a mini-split, energy-efficiency is just one of the benefits you’ll see as a homeowner.
Zoned control means less energy wasted
When you turn on a traditional forced-air AC unit or furnace, you’re more-or-less forced to cool or heat your entire home. Sure, you can try shutting individual registers and vents, but that’s not really how a forced-air system works. In fact, trying to close off individual rooms of your home can often end up spiking your electric bill instead of saving you money.
There are a few drawbacks to cooling or heating your entire home. The first is that most families spend their time together in one place, whether that’s cooking dinner in the kitchen, watching TV in the living room, or sleeping in bedrooms. In all the places your family isn’t at any given moment, you’re paying to cool or heat what are essentially empty rooms. This all-or-nothing approach to comfort can really lead to some high cooling and heating costs.
This is the primary reason why ductless mini-splits are more efficient than forced-air systems. A mini-split blower is placed in each room, giving you control over that individual room’s comfort. Many homeowners “move” their cooling and heating with them by using smartphone controls to cool and heat rooms they’re currently in and leave the others as-is.
Zoned comfort doesn’t even mean you have to turn off heat or cooling to all other rooms. If one family member likes their room a little cooler in the summer, you can accommodate their needs without freezing out the rest of the family—and heating up your summer utility bills.
Ductless skips the ducts to cut down on energy waste
Forced-air HVAC systems rely on a series of ducts to transport cooled and heated air from the blower unit to its ultimate destination: the rooms of your home. Here’s the problem: air is notoriously difficult to move. Every second heated or cooled air is in your ducts, it’s losing some of its temperature just by getting to its destination. By the time it comes out of the register, it’s not as cool or hot as it was at the blower. This means your air conditioner or furnace has to work even harder to get the inside of your home to the right temperature.
With ducts, some energy waste is already baked into the nature of the system. Then, add in ductwork issues such as cracks and pinholes. These cause heated or cooled air to leak out of the ducts as it’s being pushed out to your home, further exacerbating your energy losses. In the average home with a forced-air setup, it’s estimated that anywhere from 25-35% of all heated or cooled air generated by the HVAC system is lost through the ducts and the attic before it even gets where it’s going.
A ductless mini-split doesn’t have these problems. It skips the whole “ductwork” approach altogether and instead delivers cooled and heated air right in the room where it’s needed. There’s no energy that can get wasted in ducts because there are no ducts. Along with zoned comfort, this is one of the primary reasons why ductless mini-splits are so energy-efficient, even when compared to high-efficiency forced-air systems. The entire way they operate just has so many advantages.
Mini-splits use heat pump technology to change the temperature of your home
Most homeowners tend to confuse “heat pumps” and “ductless mini-splits” together—after all, both are types of systems that offer an alternative to “traditional” air conditioners and furnaces. Here’s an easy way to tell the difference: all ductless mini-splits are heat pumps, but not all heat pumps are ductless mini-splits. In fact, heat pumps are also incredibly popular as a type of all-seasons, forced-air system.
True to their name, heat pumps specialize in moving (“pumping”) heat energy from one place to another. They accomplish this through physics, changing the pressure of refrigerant as a means to absorb and then release heat energy. This is the same process (refrigeration cycle) used by your air conditioner. Both an AC unit and a heat pump can absorb heat energy from inside your home and release it outside, cooling the indoors.
Here’s the critical difference: heat pumps can run in reverse, allowing them to move heat energy indoors during the winter. It might not seem like it, but there’s ambient heat energy in even cold winter air. The heat pump absorbs that energy and brings it inside, warming the home.
In places with relatively mild winters (such as right here in Albuquerque), heat pumps can be an efficient way to cool and heat the home. Unlike furnaces—which combust fuel to generate heat—heat pumps only expend energy to move heat around. When your ductless mini-split clicks on, either in the summer or winter, it’s going to be using a lot less energy to run the refrigeration cycle than a standard air conditioner or furnace.
Watch: Ductless Mini-Split Installation
This video from This Old House shows an inventive use for a ductless mini-split system—cooling a garage. Watch this video to get a feel for how these systems both look and work.
You should go ductless
From an energy-efficiency standpoint, ductless systems are hard to beat. They also have a number of other advantages. It almost goes without saying, but if your home does not currently have ducts, you should go with a mini-split. Ducts are expensive to install and, in some historic properties, just don’t work. If you’re in this situation, you’ll be better served by having Wagner install a ductless mini-split to keep you and your family comfortable.
Of course, ductless systems aren’t just for homes without ducts. They’re great for home additions or spaces you want to cool / heat that don’t have ductwork. We’ve seen an uptick in homeowners adding ductless mini-splits to cool their garages in the summer—perfect for the car enthusiast—or to heat a disconnected guest house in the winter. Their versatility makes them a great option for so many scenarios.
If you’re reading this article and starting to think that a ductless mini-split is right for your home, take the next step and call Wagner. We’ll send one of our experienced HVAC technicians out to meet with you and talk through your options as part of a free in-home estimate.