Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? A window air conditioner is a practical and cost-effective way to control your indoor ...

Q: I am renting a small, old home without central air conditioning. I have a window air conditioner, and the past few years I’ve awkwardly filled in the space around it with a large piece of plywood.

The air conditioner's energy efficiency rating indicates how much electricity it uses and, in turn, the environmental harm. If you want to spend less and still enjoy great features, buy an AC with the ...