I have a HS 160R floor model 16 inch blade fan that does not work properly. When the on button is depressed the high speed indicated light comes on and the fan blades turn very very slowly. I believe that the printed circuit board may be defective. Is a replacement printed circuit board available (new or surplused) or do I have to junk the whole unit? P.S. I have experience as an electrical tech and I am capable of changing out the board.