That link is dead for me, Bill.
hulalou, 1) did you give it a couple hours? 2)There may be some obstruction in the riser tube there. If you can't feel hot, moist air coming out the top of the chimney, it may be clogged with soot. Just above the firebox you'll see a vertical cylinder about 4.5 inches across that runs from the firebox to the top of the fridge
. It's usually wrapped in some insulation. That should be getting warm, and it terminates in an exhaust chimney usually tilted over at an angle. That would be borderline hot and there would be warm moist air coming out.
They aren't hard to take apart once they're out of the trailer, but that's sometimes a little time consuming.