No matter what I do I can't get the stove pipe over 300. I have 4 and a half foot of single wall then 12 foot of double wall with 4 foot over the peak. So I don't think it is a draft problem but not sure. I can leave the damper open all day and it wont get any hotter. Wood seams pretty dry cut and stacked last fall. I plan to get a moisture meter in the morning to see if that's the problem. Any ideas?