Not trying to believe me I was running a QuadraFire for eight months on same Flue and never a problem other than it heated to well. Thought I needed smaller stove I love the heat but pampered the stove all the way. First measured draft and added damper, Worked on leaking ashpan, Dealer is in touch with hearthstone even sent pictures I sent to him during burn. He assures me that they will make it right.