No problems. I did the stove modification in Jan. '08. The black pipe shows no signs of warping or breakdown in any way. The modification did not damage the stove in any way. It did totally change the way the stove burns, and there is much less smoke coming from the old beast than used to. I do have to be a little more careful as it would be easier to overfire the stove now. As far as wood use goes, I'm kind of unsure at this point. I used 6.3 cords last year and 6.25 cords the year before. I can say though, that I started burning wood earlier last year than the year before, and that last year was quite a bit colder than the year before. So my gut feeling is that it is more efficient, but I don't have a good feeling for how much more it might be.sorry to bring back an old thread but I want to do this mod to my old Elmira insert and wanted to hear how the op's worked out after extended use.
For this reason is why i was thinking you'd need to add a solenoid or 2 that will allow or shutdown secondary air. But i was thinking the sol. would open after the upper firebox has reached a certain temp (not sure what that is ?) then of course shutdown when the water reaches it's temp.I have found that if I do not plug the inlet fitting off.. The boiler will run away. came home to 209° I dumped the heat into the garage floor. Ut would have climbed higher I feel cept it was out of wood..