Back in the day a friend in the Shenandoah mountains of VA had a two-flue chimney for his wood stoves. One in the main part upstairs and one in the finished basement. They never drew well, especially if the stoves were banked back resulting in the flue(s) not getting very warm. One night after we were, ummm, out howling at the moon and having a fine old time I crashed on the couch in the basement. The stove upstairs was running and the house was fairly tight, so the basement stove was pulling air (and smoke) down the other flue. This made it worse since it cooled the already too-cold chimney. I was about gassed which compounded the hangover. Not saying you'll have that problem but a good air supply is a beautiful thing.......
Harris dual-stage O/A
Lincoln AC/DC buzzbox
Miller 3035 spoolgun
Thermal Arc 185
Thermadyne Cutmaster 52
Angle grinders, vicegrips, the usual suspects
Two hands, tired body, not enough time...