Whoaaa! I think I need a flue damper........

I ran this stove in my shop for a season, but it was on a reduced flue from 8"(at the stove) to a 6" pipe in the shop. It's now in the house on 24' of 8" straight up, no turns. I have a pretty wicked draft and was running it last night for the 4th time. I went down to stoke it before bed and opened it up while it was going pretty strong on over a half load(flue temp was about 500). I had the door open for about 2 min while I shoved in a few sticks of oak. Closed it up and I could hear a pretty good roar. Watching the digital thermometer, it started to climb. I checked the primary & it was only open 1/8"...looked back at the thermo and it was at 700 and change & increasing like the national debt clock. So I shut off the primary and flue temps hit 850ish before coming back down. It was only 46 degrees out at the time, so I can imagine that this draft is going to really increase the colder it gets this season. A flue damper is definitely in order........

I agree, and I know the re-fuel was at the wrong time. What surprised me is the difference in this re-fuel and the one's I used to do on the 6" flue...never had a problem then. But, this is definitely a whole new ball game.

Hearthstone H1

The secondary is one year "new", no cracks or deformation & door seals all pass the dollar bill test. I only ran it once in the spring and before the porch roof was on. Back then it had so much draft it would pull the door shut once the fire was established. It's not so strong now, but still formidable.