Anybody had to put a damper on the flue to limit the amount of heat lost up the chimney due to overdrafting? I have a PE Summit and feedback that I have received indicate that I may be overdrafting and therefore not producing as much heat as the stove was designed for. I have about 30' of vertical including stove pipe and chimney and approximately 3' of horizontal. Infput on creosote buildup, success stories or other input is appreciated regarding damper installation.