Window-mounted AC units come in various sizes and cooling capacities, ranging from about 5,000 to 25,000 BTU (British thermal units). As a general rule, you need about 20 BTU of cooling for every ...

The best window air conditioners are powerful, quiet, energy efficient and easy to install. Our top picks for 2025 include models from LG, TCL, Whirlpool and more.

Clean your window AC unit about every 60 days if it's in continuous use. If the unit doesn't serve as your heater, store it in the off season so dirt doesn't accumulate. If you do take it out of ...