I have had the same problem as you guys (blower only working on number 4)i took the blower out and checked the motor out ,it was a bit gunked up around the bearings ,so a good clean up and some wd40 later it was spinning fine ,i took the resistor pack out and tried the blower it still worked only on number 4 not sure if this should have done this with no resistor pack in i thought it shouldnt have worked at all with nothing in,tomorrow im off to maplins to buy one of those 215degree resistor will let you know how it goes