This is Doug of Kalindi and Doug. After researching this site and examining my Acorn 215, I have created a diagram of the air flow for a base burner stove in both start-up and base burning modes. Please let me know if there are any correction that I need to make.
Doug, Nice drawing! I don't know how the Acorn works, might be exactly as you have drawn it. Compared with my Glenwood, what you have drawn for your valve and the two smoke pathways are a bit different. I'll call those two paths the direct vent path and the re-circulation path. Lets see if I can explain. Your drawing shows the two paths almost as two separate parts; the baffle on the bottom is being shown as horizontal; in your drawing, the valve when set to direct vent path has no effect on the re-circulation path. In the Glenwood, the two paths are housed in the same part, the part that goes down the back of the stove. The baffle in the bottom is actually vertical and the valve when set to direct vent actually closes off the re-circulation path. Don't know if this makes any sense...