Lopi Freedom Bay- odd behavior

Hi folks, first question here.

I just moved into an old house with a masonry fireplace in the middle. The fireplace had been converted to a primary heater with an EPA non-cat Lopi Freedom Bay insert in the early 90s using a direct connect to the existing 8x8 clay chimney liner. The house is from the 60s but is insulated and is only about 1700 SF of ranch. No rain cap and reportedly annual chimney cleanings which involve sliding out the insert since the inside direct connect is such a lousy system.

The stove was used by the previous owner right up until I moved in. The plan is to have the sweep out very soon to inspect the stove, clean the chinmney, and slip in a SS liner. Then I can clean it out myself through the stove. Until he can come out I am burning the stove, my first EPA stove, and have a question.

I set a Rutland thermometer above the door as the manual states and have been watching my temps. Now I am worried a bit. The manual lists 800 degrees as overfire or when the stove glows red. The manual also is good about showing how to stoke and load the stove for overnight burns. I run the stove in the 400-500 range during the day with no problem and nearly nice clean emmisions and then before bed I stoke the firebox pretty full, get it going real well, and then damper down to almost closed. The fire looks to be ready for an all night burn with whips of flame licking off the front of the large fuel load and the burner tubes keeping the secondary flames flickering. Then I wake up a couple hours later and find that the stovetop is 725 degrees and the fire is rolling pretty well above the fuel load. I then shut the draft completely and the stove cools down over the next stressful hour or two. Only coals in the morning. The good news is that the overfire I had was easily controlled by shutting the draft, the room didn't heat up much though and the paint didn't burn. If I had shut the draft down to zero before going to bed I thought I would snuff the fire.

Should I be able to stuff a firebox full of firewood, get it going, and then completely close the damper for an extended burn? As it is, I am worried about overfiring unexpectedly. When I say "stuff it full" I really only mean 3 pieces of wood split to 6" plus the coals and ash from the days burn. There is still room to the secondary tubes and the 24" wide firebox leaves a few inches on each side of the 18" or so wood.

Thanks in advance.

Thanks guys I will read up on those searches. Do you folks with the non-cats completely close the draft control after stoking for the night? At this point I am afraid to pack the the box with much wood.

I thought about it today and after the wife was able to hold 500 degrees all day without much effort I have resolved to be a wuss and lightly stoke the fire until the SS liner goes in. Any experimentation would be a waste of time since the liner should change the operation substantially. So tonight, 23 degrees outside, I will put 2 larger logs in, let them char, and slam the draft down before retiring for the night. In the morning, a new fire will likely need to be started unless I find myself awake late at night and throw a piece in.

I will gladly present the behavior of this stove with the new liner and hopefuly I find it much more predictable. I can easily prevent runaway in the meantime by being overly cautious.

Thanks for the input, I think I'll go enjoy my Pyramid snow cap in front of the cheery 55 degree Lopi.

I've been shutting the draft to zero these last couple nights but not stuffing in a major load, like maybe 2 new ones atop a good bed of coals. I let it roar and then shut it down in two stages. The logs burn down to almost nothing but the window is super coated with the goo that won't come off with water and ash. It burns off with the first hot fire though.

I've been running it up into the 600s pretty regularly during the day now to get more comfortable with the high heat. It works well but takes a lot of wood to get it that hot. The stoves seems to have a sweet spot at about 500.

The chimney sweep guy comes out on Thursday to set me up with a liner, inspection, clean the old flue, and whatever else needs done. I hope it isn't too pricey, but it is a worthy investment.