Why do window ACs actually need a window? On the surface, it feels unnecessary — after all, the unit is clearly designed to blow cold air from the front. Why can't you just set it on the floor like a ...

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.

As is the case for many people, my home cannot be retrofitted with central air. My 100-plus-year-old Brooklyn apartment, which features prominently in my seven years of air quality reporting for WIRED ...