Hello hearth.com and fellow members! I am new to owning a fireplace / stove, and could use some help please! I recently bought a house that has a Country Flames Catalytic insert on the fireplace. I believe it is the BBF or O2 model (the manual that was left says it covers both oven models). I read the manual to learn how to use it, and I think I am using it correctly. I used it 3 times so far and it seemed to work pretty well. In each case, I started a fire, let the oven get up to about 400 or 500 degrees, then I shut the damper and it heated up, and eventually warmed up my living room nicely. However, last night I set out to do the same thing, and within a few minutes after lighting it smoke began to pour out of the two bottom vents, into my living room! The damper was of course open, as it should be. I opened the stove door to take a look inside, and a ton of smoke poured out, so i quickly shut the door. I tried turning on the blower fan, and I also opened my windows in the living room in order to air out the room. I then tried shutting the damper and the vents, in the hope that it would put out the fire. The fire seemed to burn out, but smoke still slowly seeped into my living room through the vents for about 2 hours, even with the vents closed. The house got really smelly - it was not fun! I opened the damper again, hoping the smoke would go through the chimney. I was really worried about my family breathing this smoke in. Eventually I snuffed the fire out completely (with a few glasses of water) and everything died down and it stopped smoking. Does anyone have any thoughts of why this might have happened? I thought the oven was sealed from doing this sort of thing. I can tell you that I did not clean out the oven from the prior 3 fires, and there was a bunch of ash and debris in there. Could that have caused the problem? I am going to clean it all out and try it again. But I am really worried about this smoking again into my house. Any insight would be appreciated. thanks!