The size of the air conditioning system that is right for your house depends on a number of things, including the size of your home, the level of insulation, the number of windows, the type of roofing, and the local climate. A licensed HVAC professional can perform a load calculation to determine the appropriate size of the air conditioning system for your home.
It's important to choose an air conditioning system that is properly sized for your home, as an undersized system will struggle to cool your home adequately, while an oversized system can lead to excess humidity and higher energy bills. A licensed HVAC professional can help you choose the right system for your home's specific needs.