Last night and one other recent evening, my PE TN19 would not slow down. Afraid to go to bed until the two big pieces of ash in there started to slow down a little. Took a look inside little bottom plate where I can feel air control lever (they call it a quadrant assembly on website but don't show how it's put together), and linkage seemed fine. I can feel a semi-circular hole when it's is in the full open position and that that hole is almost completely closed when lever in fully off position. There is only a tiny corner open in there. I suppose that is how it should be. Door and gasket are fine. Beginining second winter with this stove, and no such problems last year. Any ideas??