We got this because we had a major mold problem and needed to do extensive house repairs to get rid of the mold. At first we weren't sure how good it was working because it was always orange but it turns out our air was just that dirty. After a couple weeks it started turning blue and has been ever since. We've only had it for 3 months but with how dirty our air was I'm surprised to see how long the filter is lasting. The indicator still shows it's at full life.