kstills wrote:I'm glad to see this thread, because I have a similar type problem.
I just took delivery on a new order of coal, and I'm starting to get a ash dam form at the middle/front of the grate. It idles fine, but when I get a heat call and the stoker goes full out, the fresh coal builds up behind the damn and starts to spill over the sides of the grate. The real negative effect is that the fire is not as hot (it burns more like wood then coal) and it takes forever to hit the LL on the aquastat to restart the circulator.
My setting hasnt changed (I put tape on the screw to make sure it was always exactly the same spot) but I'm thinking I'll have to change it to run slower.
Did you have the grate out for any reason. I have seen that when the grate is not fully seated in the front properly.