Tremont Question?

So we rented a house with an existing woodburner called a Tremont( no owners manual), decided to give it a try, could not access the flue so I burned a creosote removal log ( yea I know it's probably not the best solution, but the best I was gonna do). I figured pretty much everything out on controlling the air, heater, only used it a couple times.
Now here's my issue, the next day after a fire we keep getting a smoky residue smell in the room, it seems like some sort of "backdraft", I empty the ash tray and remove any un burnt logs. It takes a few days for the odor to dissipate.
I'd like to keep using the unit but don't want my house to smell like I'm smoking Virginia hams all day.
I've attached a couple picts, the only piece I can't figure out is the small shaft that screws into the grate, it appears broken, but I can unscrew it. The flue apparently cannot be closed, so I am at a loss on how to stop the smell, any ideas would be appreciated.
Al

Don't know if it has a liner, when I took the top cover off I can only see that the box goes into the flue. Being that I am renting, not going to pursue this too far, I already have a list of things that I haven't been able to get done that are higher priority.
tks

Here's the best I can do with pictures of the flue box, and I will not use it till I get this resolved, don't want the smoke or the possible danger.

mellow said:

Good ol treemont, those things are built like a tank. It looks like it has a rectangle exhaust which more than likely means it is a slammer or has pipe to the first tile only. You really need to have this inspected before burning in it. That stove also will not do that great with wood since it has the shaker grates that are meant for coal, that is what that rod above the ash pan box is for. It should have had a baffle above the firebox but that probably rusted and was removed.

Click to expand...

Thanks,mellow that explains alot, might have some firewood for sale and turn up the thermostat