Ductless split systems work somewhat similarly to a central air conditioning system, in that there is an outdoor unit that vents heat using refrigerant, which is then cycled to the indoor unit, where warm air passes over coils containing the cooled refrigerant.
The difference is that with a central system, the cooling happens in an indoor unit which is attached to your furnace, with air then being circulated through the ductwork in your home.
With a ductless system, this heat transfer and cooling process happens in the indoor unit directly in the room where the cold air is blown.
So one (or more) outdoor units is installed in a strategic location. Then small holes are drilled through the exterior walls to pass the cooled refrigerant tubing to where the indoor unit or units will be mounted.
Then everything is sealed, and once the electrical setup is done, you’re all set!
Ductless split systems come in two basic varieties, ones that only cool (ductless air conditioners) and ones that heat AND cool.
A heating ductless system can be a good option for supplementing your existing heating system, or as your primary heating system if you live in a generally milder climate. Ductless heating systems are not well suited as the primary heating system in most regions of Canada, as they are not designed to work in very cold temperatures, below about -20 degrees Celsius (some models mightwork up to -25 degrees Celsius).
So if you live in Vancouver for instance, a ductless heating system may be a viable option. But in most other parts of the country, there will inevitably be a few extremely cold days each winter, and you don’t want to be caught without adequate heating during a cold snap. Even Southern Ontario, although you’d likely be fine most of the time, extreme cold periods do happen.
Aside from this, ductless heating/cooling units can be a good option for some homes. The rest of the information found on this page generally applies to both ductless air conditioning systems, and heating models alike. The same factors, advantages/disadvantages, and brands are relevant regardless of the type you buy.
That being said, the best thing to do is request a free estimate from a Certified local professional for custom recommendations and pricing.