Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not good

Fan speed before install was around 2500 RPM, after install it was around 2250 when controller was all the way up. As I turned it down nothing happened until it was all the way down, then it suddenly dropped to 1250 RPM. There is nothing in between. And if I shake or touch the button with it all the way down the fan speed will jump to 2250. It just does not work as it should, I finally got it to stay at 1250 but if it gets bumped it will jump back to 2250. I would not recommend.