My Grandmother had a hovabator 1602N i believe it is. with the allen wrench shaped screw on top. the problem is when screwed downward, it doesnt "hit" the littl emetal nipple thingy underneath. Can i adjust the position of the thingy underneath? i jimmy rigged the fly nut to go down ont he bottom to make a connection but my range is like 25 degrees and that will not do. Thanks for any information. btw- it has a built in fan that comes on when the heat turns on.. if that matters?