titleist1 wrote:You do need to cap off the bottom of the chimney on the outside. Leaving that open will rob the draft that is supposed to go through your stove.
It looks like you have a barometric damper. Since you have already experienced CO issues, I would cover the opening on that with foil until you get a manometer to measure your draft.
It's hard for me to tell from the other pic, but it looks like you have a 6" pipe from the stove going into an 8" pipe that goes through the wall? If so stuffing insulation between the 6" and 8" pipe is the correct thing to do. Blocking that gap will help all your draft come through the stove.
When was your flue pipe last cleaned, especially the horizontal sections?
I will pull the insulation on the chimney on the outside of the house and install the cap. I will leave the insulation on the inside between the 6" pipe and 8" pipes and I will cover the damper and check the draft with a manometer. I just had the pipes all apart and cleaned up this winter...about 3-4 months ago so that should not be an issue. I will keep you all posted. Your guidance is GREATLY appreciated! I am very glad I found this forum!