Unlike window air conditioners, portable air conditioners roll easily from room to room and are quick to set up, with no labor-intensive mounting and very few tools required. Most just require a nearby window and wall outlet to get cold air flowing. Portable air conditioners have an internal fan that moves hot, humid air over a refrigerant-gas-filled coil to cool and expel it into a room to lower the temperature. Because they can be moved from room to room, you can take the cold air with you instead of running more energy intensive central a/c or buying multiple window units. To find the best models to recommend, we tested air conditioners from trusted brands like LG, GE, Black + Decker, Midea, and more.