First thing, you need more pipe on the outside. I would put a 4'er on if i'm going through the trouble. Do you know what kind of pipe they used? Simpson is what we use and we found that the back collar where the pipe hooks to the stove is too short and we don't get a good pipe fit. Now we put a close clearance adapter on the top of the stove and now have no problems. Unless you have single wall pipe on the inside instead of the double wall. Check all gaskets and make sure they are sealing correctly. 700 deg for a cast iron stove is way too hot, be careful you don't crack your stove. (warranty doesn't cover that) Google cast iron temps for stoves 450deg is what you want to run that thing at.