Consumer Reports tested several types of window air conditioning units to test their cooling ability.
Portable air conditioners sound like an easy solution for cooling a room that can't accommodate a window air conditioner, but many are returned by unhappy customers.
So Consumer Reports tested to see if there are some good choices.
With temperatures rising outside a seemingly easy fix is a portable air conditioner. It draws in warm air and exhausts it outside through a hose that connects to your window.
Consumer Reports tested eight from brands including Honeywell, Haier and Frigidaire. Prices range from 250 to more than 500 dollars.
Consumer Reports used a special chamber to test their cooling power. The temperature outside is kept at 90 degrees, the humidity at 70 percent. Inside, each air conditioner is set to 75 degrees.
Strings of thermocouples record temperatures throughout the room. The results were disappointing.
"None of these units, not even the biggest ones, could get our test chamber below 80 degrees even after an hour and forty minutes," said Bob Markovich, of Consumer Reports.
That was true even of the most expensive unit tested, including a $550 Honeywell which promises it "cools up to 550 square feet." It struggled to cool the test chamber, which is half that size.
"Window air conditioners are much more effective and they tend to cost less," said Markovich.
Consumer Reports found several window air conditioners to recommend. Top-rated for larger rooms, a $350 LG. For medium-sized rooms an LG for $240. And for smaller rooms a $210 GE is a Consumer Reports Best Buy.
Consumer Reports says be sure to pick the right size air conditioner for your space. If the unit is too small, your room won't get cool enough. But an air conditioner that's too big may make it feel cold and clammy.