Ductless mini-split system does not require ductwork, making it the more convenient cooling and/or heating option for older buildings with thick walls. Unlike an air conditioning unit that goes on and off throughout the day, mini-split system keeps your room temperature at a constant temperature.
These systems run very quietly, and are easier to install. Their compact size also allows for greater flexibility in temperature zoning — air conditioning is limited to the rooms in which the indoor units are located. Finally, many ductless A/C units are Energy Star certified and perform better that other types of air conditioning systems when it comes to energy efficiency.
A central air conditioning system treats air at a central location and distributes it to and from rooms by one or more fans and a series of ducts. Supply duct distribute cool air from the air handler to the home. The air becomes warmer as it circulates through the home; then return ducts carry warm air back to the air handler to be filtered and cooled.
Central air conditioner is most likely your best option if you want to keep your whole house cool. The system is virtually invisible so if you’re very particular about your décor, this may be a better choice for you.