My house is super tight. Once the house is cool, the AC doesn’t run much so it doesn’t have the time to remove a lot of humidity. I put this dehumidifier in my master bedroom initially (abt 700 sq ft including closets and bathroom). It took the humidity from 65% down to 45% in a matter of hours. Then I moved it to the attic. All of the humidity rises to our attic. It’s been running there for a few weeks and has kept the 1500 sq ft area consistently at 45%, just as it’s programmed to do. I’m not sure how often it runs (it’s drains automatically up there) but it’s probably most of the time. Very happy with its capacity and performance. Hopefully it will last for years. I’m considering buying another for the basement, where I have a built in dehumidifier that isn’t really doing it’s job.