I have a new rocket stove in my basement. It works fine when it is going good but as the fire dies down, it starts to smoke back into the house. My house seems like it is starved for air (negative pressure). When the force of the fire dies down, the air starts coming back into my house. I have a 6 inch system. The exhaust is going out the side of the house. If I leave a window open it seems to help some, but that kind of defeats the purpose. I tried running a 6 inch fresh air line into the house to feed the fire, but it didn't help that much when the fire is going out. Also, I read it is not safe so I don't want to go that route. I am getting close to giving up. Any ideas would be much appreciated.