Choosing The Right Mini Split System For Your House or Space

If you’ve never heard of mini splits or mini split systems, you’re not alone. Simply put, they are ductless cooling and heating systems. Basically these are systems that don’t need any ductwork to be installed in your home or workplace. They simply use copper line sets for refrigerant flow.



A mini split system consists of two parts: an outdoor condenser and a single or multiple indoor evaporator air-handling units.



This technology isn’t new and in fact has been around for more than 30 years. Mini split systems started being used in Europe and Japan and eventually made their way to North America. Most of these systems offer both cooling and heating but some only offer cooling, so you need to check before purchasing your unit in case you’d like complementary heat.





Mini split systems are also typically designed to cool and heat a single zone but there are multiple zone units available as well.


*Keep in mind that mini splits are much more productive at cooling large spaces than they are at heating them. There are a couple of reasons. When you cool a space, typically on average you want to go from 30 degrees celcius to 20 degrees celcius. (86 degrees farenheit to 68 degrees farenheit) but when you heat, you typically  try to go from 0 degrees celcius to 20 degrees celcius(32 degrees farenheit to 68 degrees farenheit) -- thats quite a bit more. The placement of wall units is also typically high on the wall so this favors cooling instead of heating.(cool air goes down while heat rises)


Another thing you need to know is that - as it gets colder outside, there's less heat available to bring inside, so the heating capacity of a heat pump is highly dependent on the outdoor conditions. Basically, the capacity goes in the opposite direction from the load. This is the same concept for all heat pumps. For example – a typical 12000 btu mini split system will generate about 3500 watts of heating which is pretty good but as the temperature goes down outside, the amounts of btus it can produce will decrease. You will get the most bang for your dollar above freezing point in regards to heating but when you go below this temperature, expect heating output to decrease quite a bit until there is no heat left outside to bring inside(This is usually around 5-10 degrees farenheit or -10 degrees celcius). This is basically the same for all heat pumps unless they are bivalent systems. Regular baseboards have a better position for heating flow (on the floors) since heat rises and can produce much more heat to accommodate large spaces and homes in tough climate. Expect that you’ll need about 1000 watts per 100 square feet to be safe. In essence, always make sure that you have an alternate source of heating as the temperature does below freezing point just in case.


If you are a handy man or a do it yourself type of person, you can save quite a bit of money by purchasing a system and installing it yourself. Although this will void your warranty, with the right tools, you can usually save around $1000 which can make it worth it! The real benefit here is that you save on the installation costs. There are diy systems on the market but we recommend you simply getting a standard machine as they have been tested and proven to be more reliable. Why are many people going this route? The average installation of a mini split unit will usually cost you between $800-$1500 depending on your area. 



single zone ductless mini split systems    Multi Zone Ductless Mini split Systems



Mini split systems aren’t perfect for every space so you need to be realistic when purchasing one of these systems. They do come with serious advantages for many different applications.


The following examples are great situations for a mini split installation:


  • - An existing home that has no ductwork or a new home being built where no ductwork is planned. If these homes already have radiant or electric baseboard heat, a mini split system is ideal. Such a system will save you time and money.
  • - Rooms or zones in the building that aren’t always in use. You can simply turn off the system to save some money
  • - Additions or buildings where extending or installing ductwork just doesn’t make any sense.
  • - Spaces that are close to areas with no insulation and that are unconditioned such as garages, attics and basements. The ductwork would be exposed to crazy temperatures and this wouldn’t be energy efficient.
  • To avoid using ductwork that is exposed to large losses of energy. Installing a mini split system can save you money on your heating bill in these types of situations.


The following are examples of when not to install a mini split system:


  • - You have existing ductwork that goes through your entire building. You might as well use these ducts to your advantage and install central air.
  • - You would like to use these systems to primarily heat very large spaces, entire houses, entire condos, entire mobile homes and buildings. Make sure you check how many heating watts the machines generate and see if they will fit your need.


When you choose your system, always try to figure out how much cooling in BTU you will need for your home or living space. Each installation is different and each home of space is different as well. some homes have barely any insulation while others are well insulated. Some spaces are filled with sunny windows while others aren't. Climates vary as well.


*A general rule of thumb is to use 1 ton per 500 square feet or 12000 btu per 500 square feet to be safe. 


You can always check the following chart if you need additional help:


Mini Split Btu calculator


range for ductless btu



When purchasing my mini split system, will I need copper line sets?


This depends on a couple of factors.


  • - If you purchase a do it yourself ac system by Caribou, they already come in the the box and are pre-soldered to the units.
  • - If you purchase a standard mini split system and your installer told you he already has the copper piping, you won't need them but the installer will charge you extra to cover his copper.
  • - Some of our mini split systems already come with installation kits and with copper linesets, make sure to double check that the length is ok for what you need.


Do I need a rack, bracket or support for my mini split system?


Yes you do, this makes for a professional installation and also helps your machine avoid various types of weather damage. it makes sure the condenser doesn't tip over and will ensure that you are covered by the manufacturer's warranty.


Aluminum Ductless Mini Split brackets