hey guys i have a vogelzang ponderosa stove i just bought and installed in the existing chimney of our house. im not getting a decent burn unless i leave door open then shut it. itll do a secondary burn after shutting the door for 30 secs then stop. glass is black after couple hours of a burn. the chimney setup is about 25 ft from the stove. its on 1st floor so theres about 15 ft below it thats sealed. clay lined square. dampeners seem to do nothing. wide open or closed. any advice would be great thanks in advance guys!