The standard AC unit is a split system (aka a central-air unit). The reason behind using a split system is that you can put the condenser coils in one location outside of your house and the evaporator coils in a central location inside your house. From this central location, ducts can carry cooled air all over your house. However, there are times when a central-air system is overkill. Thus, you should have a conversation with an HVAC specialist to decide if a mini-split system might be a better choice for your home. 

What Is a Mini-Split System?

Like a central-air system, a mini-split system will have one set of condenser coils located outside your house. Unlike, a central-air system, a mini-split system will have up to four sets of evaporator coils located inside your house. These coils are sized to cool one to two adjacent rooms, and thus, they are placed directly in the rooms you want to cool. In other words, a mini-split system is not necessarily designed to pump cool air into your whole house. 

Why Use a Mini-Split System?

If you have more than four to four rooms in your house, you may wonder if a mini-split system is a good fit for your home. You need to think about whether all the rooms in your house need cooling in order to decide if a mini-split system will work for you. For example, if you have storage rooms, craft rooms, or guest bedrooms that you don't constantly use, then you probably don't need to pump cool air into these rooms. Simply closing the vents does not stop your central-air system from pumping the same amount of air, so using a mini-split system might be a better choice. Furthermore, if you have rooms in a basement level, they will likely not require the same level of cooling as the rest of your house, so you may place evaporators in the upstairs of your house and leave the basement alone. 

A mini-split system may not work for every home, but using one can help you target cooling to the rooms that most need it. Furthermore, because each evaporator unit will have its own thermostat, you can shut off the evaporator unit to a room as you exit it without affecting the cooling happening in other rooms in your house. Thus, mini-split systems tend to be more efficient than central-air systems. Thus, in the interest of saving money alone, you should talk to an HVAC technician about using a mini-split system in your home.