Portable air conditioners are increasingly popular among homeowners; they are portable, flexible, small and easy to install... But they can be a very poor choice; most of them are energy wasters. Before any purchase, learn the pros and cons about portable AC.
Portable air conditioners are easier to install than other types of AC, but... they aren't as portable as buyers might hope.
They are relatively heavy and bulky and possible wheels or handles will not make them as easy to move around as you may expect; you'll need to place the unit somewhat close a window to vent outside, or to drain the condensate outside the room.
Unvented portables are a poor choice. Without a venting system the portable will cool one part of the room/house while heating another. Non-vented portables are very ineffective. Avoid them.
Many portable air conditioners come with an installation venting kit (a hose system) for a sliding door, window or wall: portable units are either dual or single hose units. Single hose units have only one hose - to bring in outside air and to vent exhaust air. In dual hose models these functions are performed by different hoses. Hoses can be cumbersome, and aren't aesthetically pleasing. But they are crucial in any portable, and dual hose portables perform a lot better than single hose units.
When buying, pay special attention to the portable capacity (the BTU's you need to cool a room). As other types of air conditioners, to perform reasonably, portables have to be sized according to the area they have to cool…
Since they do not cool as well as window air conditioners, the tables used for the sizing of these other units have to be adjusted. You may use the following rules: 8,000 BTU: 150 sq feet; 10,000 BTU: 250 sq feet; 12,000 BTU: 350 sq feet; 14,000 BTU: 450 sq feet. Consider also the same adjustments used for the sizing of window air conditioners (see: Room-window AC).
Expert and owner reviews On portable AC
Most portable AC models perform poorly, and are noisy, and typically more expensive than window AC units.
But ConsumerSearch have identified some models with good overall ratings, namely those of MobilComfort and Newair… To take a look at customer reviews in Amazon.com see: Portable.
Like other air conditioners, portables also need drainage. Some portables have a pan or bucket that needs to be regularly emptied; others use the hose and some models recycle the condensate, using it to cool air. Unfortunately, this last method may not work flawlessly.
Portable AC energy efficiency
When buying, it may be helpful to consider units with a good energy efficiency ratio (EER). A portable AC with a high EER will cost less to operate (there isn't an Energy Star or any other equivalent certification and rating for portable AC).
Pay also attention to the warranty; most portables have only a one-year warranty.
Consider portables with handles, wheels or casters; prefer also dual hose models (see Box).
5,000-7,000 BTUs portables may cool a small room and can cost you about $250-$300, which is not very different from the prices of window air conditioners or the price of some ductless mini-split systems with a single air-handler.
Larger portable AC units may cost a little more. A 10,000 BTU unit (to cool a 250 square feet room) may cost $350-$400 online; for reviews on portables in Amazon.com, see: Portable AC.
Alternatives to portable air conditioners
Portable air conditioners are very questionable in their effectiveness. Window air conditioners and mini-splits AC units are much better for energy savings and will not cost you significantly more.
See: AC Alternatives