I have a Professional Char-Griller Gas Grill & Smoker with a fire box attached to the side of my smoker. I have a hard time controlling the temperature either going too hot or not hot enough when smoking meat. I use charcoal to start with then adding wood chunks to the charcoal. The amount of charcoal I start with is full in a chimney starter. My question is should I use small wood chunks for smoking meat for 6 hours or more or should I use larger pieces of wood? I am not talking about the small wood chips. If I use the larger wood then should I use less charcoal or no charcoal? I am also confused about opening the damper to allow more/less air flow. If I increase the opening of the damper this will allow more smoke thus allowing the wood to catch fire and increase my temperature. Yes I am using the thermometer the is on the cover of my smoker. Any help or suggestions is greatly appreciated.