Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Piece of Junk

I had this on medium for 30 days and it began to howl. Now it howls all the time and it is too loud to run it. For an expensive air cleaner it is cheaply constructed. The inner components are made out of styrofoam the type you see on a disposable beach cooler. Now I have to pay shipping both ways to the manufacturer to have it fixed. Stay away from this air cleaner.