Note the Noise
Models that scored excellent or very good in our noise tests are so quiet that the only sound you might hear is the fan running. Air conditioners that scored fair for noise could disturb light sleepers when the setting is on low, and are distracting to all when set on high.
Factor In the Window Location
Window air conditioners generally do a better job blowing air in one direction. That can be a problem if your window isn’t centered on the wall. To uniformly cool a room, you’ll need to direct air to its center, so check whether your A/C needs to blow air to the right or to the left. Some have fan arms that swivel.
Install It Correctly
To get the most from your window air conditioner it must be properly installed. Most units are intended for double-hung windows. If you have casement windows, you may want to consider a through-the-wall air conditioner. Make sure your window unit is level so that it drains correctly. And move any heat-generating devices such as a TV or lamp away from the unit.
TO READ MORE GO TO: https://www.consumerreports.org/cro/air-conditioners/buying-guide