The size of your apartment will be one of the most important factors in which type of air conditioner is most suitable. A studio apartment and a three bedroom will have very different cooling requirements. If you only need to cool a studio or perhaps just one room of a larger apartment, smaller systems like window units or portable units may be suitable. A ductless/mini split units will generally be the best option for larger spaces.
Window Units
If you’re renting or want to avoid serious wall modification, this is the way to go. Window units provide the most cost-effective and painless solution to cooling a single room. The units are relatively cheap and they have a lot of cooling power. The installation of these is pretty simple and they’re very portable.
Portable Units
Portable A/C units are commonly used in bedrooms, dens, computer rooms, and many other places. Technically, all the parts are physically in one box, but you’ll still need a hose to carry air inside and out through the window, so these devices usually sit on the floor near a window. A portable A/C is portable in the sense that it allows you to change the point where cool air is blowing. However, it can only go as far as the exhaust hose stretches, so its mobility is limited.
Portable units are for those who absolutely can’t use a window unit and aren’t able to do any wall modifications. As Consumer Reports points out, they’re costly and not very efficient in general.
Ductless/Mini-Split Units
Mini-Split units consist of two parts: the indoor component that you can mount on a wall, and the outdoor component that sits outside your home. A “ductless” means that you don’t need to have a complex system of ducts installed throughout your entire home.
Split units are comparatively simple to install as they just require drilling a three-inch hole in a wall and running wires through it. They are very quiet, yet powerful – their cooling power is among the closest you can get to real central air without tearing apart all your walls and ceilings to install. The main disadvantage here is that the initial installation of mini-splits is usually costly which can put off some homeowners. In addition, you can’t move them from room to room like you can with a window or portable unit and will also still need multiple units to cool separate rooms.