Oxygen starved fire or so it would seem

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If it makes you feel any better there are quite a few people who have to start fires with the door open depending on the stove, I really like that feature on the Lopi.
 
I think a 3' section of Class A would be a worthy investment for you.

And yes, the bypass damper feature on the Lopi is indeed very handy. I've started up a cold stove with it open and closed, and it does make a big difference having it open (just don't forget to close it, or you can easily overheat your flue). And when it comes time to run the brush down the Class A, you just open it up and sweep the soot into the fire box. The only downside I can see to it would be that perhaps over time, with the constant high temps needed for secondary combustion in the fire box, is that the damper plate or the yoke that attaches to it might warp. I'm on my third season with the stove, and so far I can notice no difference in performance so it's clearly built well.
 
Well the fire is cooking now and I'm gonna let it burn for a while with the door cracked. I'm pretty sure I'm going to add another length of chimney. I'm at the point now of already needing a roof guy kit which I was hesitant to add. Not of big fan of putting more holes in my roof I guess. I think I'll go ahead and get 3' more of pipe and install the braces. One other question, and another reason besides the braces, that I was hesitant to go any higher is on the cold chimney issue. I was concerned that adding more length outside the home would equal more length susceptible to cooling and therefore loss of draft. Any merit to these fears?
 
The only thing you might notice is more soot in the last section of pipe. I have around 5' of exposed Class A, and I have no problems with draft or creosote, but I am burning wood that's been cut/split/stacked for a minimum of one to two years.
 
I have right about 3.5' exposed right now. Guess it's time to add some more pipe. I'll update this post when I get the pipe added on. It might be a few weeks since I'm in the process of trying to finish our deck, cut firewood and finish the lawn before the rains come. I've got about ten pokers in the fire right now. If only my fire would burn right, I could take one of them out! I'll defiantly post till I get it right though. I hate reading a thread only to be left wondering how or if they ever got the problem fixed.
 
The wood you are burning now, when was it cut/split/stacked? Sorry if you already said, but if you did I missed it.
 
I never really did. Not sure on any of those fronts. The kindling is from a tree I took down about a month ago. However, it's been dead for around three years now and the small limbs I put on cracked readily in your hands. The actual wood I'm burning is from a buddy who left it behind after camping. I know he cuts year round so it's hard to say for sure. From what little I know, I'd say it's seasoned but I'm no expert. I can definitely say it doesn't sizzle when I'm cooking it. The wood seems to be burning alright but having said that I'm also not getting my flue collar temp up past 250 degrees and I'm still seeing the same issue with not being able to close the door without the fire dwindling and struggling to burn. The instant I reopen the door though, the air rolls in and the fire dances likes it's just been given a new lease on life. I think I'll get a small pile of wood from my dad who keeps a well seasoned stack ready at all times, just to eliminate any potential of the wood being the issue. I could very well have a combination of problems causing this failure.
 
Pagey said:
The only downside I can see to it would be that perhaps over time, with the constant high temps needed for secondary combustion in the fire box, is that the damper plate or the yoke that attaches to it might warp. I'm on my third season with the stove, and so far I can notice no difference in performance so it's clearly built well.

I'd be really surprised if it ever went bad. It's pretty beefy. I peek at mine every year when I clean, and no signs of warping yet.

As to the issue at hand, it does sound like a combination of things. I'm guessing that the OAK will make a huge difference, and a taller chimney might help, but really heating up that flue will help as well. Leaving the door open a crack during cold start up and using smaller pieces for that first fire gets the draft going. Try a small, hot fire using smaller splits of dry wood with lots of air to get the machine warmed up first. Then you should be able to reload with larger pieces and start shutting down the primary.
 
skidud said:
I never really did. Not sure on any of those fronts. The kindling is from a tree I took down about a month ago. However, it's been dead for around three years now and the small limbs I put on cracked readily in your hands. The actual wood I'm burning is from a buddy who left it behind after camping. I know he cuts year round so it's hard to say for sure. From what little I know, I'd say it's seasoned but I'm no expert. I can definitely say it doesn't sizzle when I'm cooking it. The wood seems to be burning alright but having said that I'm also not getting my flue collar temp up past 250 degrees and I'm still seeing the same issue with not being able to close the door without the fire dwindling and struggling to burn. The instant I reopen the door though, the air rolls in and the fire dances likes it's just been given a new lease on life. I think I'll get a small pile of wood from my dad who keeps a well seasoned stack ready at all times, just to eliminate any potential of the wood being the issue. I could very well have a combination of problems causing this failure.

This sounds like a combo of so-so wood, combined with poor draft. If outside temps are also mild, the short stack probably can't draw well enough. The best way to figure this out is to eliminate unknown variables. Take a planned approach.
1) make sure the air control is open (all the way out)
2) start a fire with dry kindling. Get some carpentry or cabinetry scraps and use them to get the stove going well
3) open a nearby window about 1" and leave the stove door cracked open about 1/2"
4) once the kindling fire is burning well, put on a couple 2x4 scraps, let them get burning well
5) then put on the splits of dry wood, allowing an air gap between them
6) once the fire is fully involved and burning strongly, close the door on the stove.

If this fails, the next thing is to make sure there are no obstructions in the flue and the cap screen is clean. If all the above fail, the stove has insufficient draft. It will need more pipe. To check this theory, get a *temporary* 3 or 4' length of inexpensive galvanized 6" heating vent pipe from the big box store. Pull the cap on the chimney, then cram the venting pipe, crimp down into the chimney. Leave the cap off and try lighting a fire with this temporary extension. If the stove lights up well, try closing the window, after the fire is fully engaged and the stovetop is over 300. If the flame dies back, it will also need an OAK.
 
Hrm. How did you make out Skidud? Did you try letting the fire roar a bit?

I agree with BeGreen, try some wood that is kiln dry. By a couple of 2X4s or something. Not pressure treated!

With my air tight basement, I always open a window in the nearby room for a few seconds before opening my damper and then cracking the door open for 5-10 seconds. THEN I reload. I keep my door open for 2 mins or so, close the door, bypass damper and then turn down the primary air intake (once my stack temps are nice and high and my secondaries are going nicely).

FYI for all the members here, the Osburn 2300 also has a bypass damper in the back. It's not just the Lopi. :) Too bad the Endeavor is unavailable in Canada!!

ANdrew
 
skidud said:
I know the inner liner wasn’t at 500 because I borrowed my brothers laser thermometer and shot a beam in through a vent slot in the outer wall.

You can't do that with a "laser" thermometer. I know, I know... you can see the laser dot, but the actual area that the internal sensor covers is about 1" in diameter at the very closest you can get to the target. The dot is only a pointing aid and has absolutely nothing to do with taking temps.. Most likely, you were reading only the outer surface.
 
Is your upper baffle board or brick pushed all the way to the back so you have about a 2.5" opening up front on top?
That was an issue with my mine. Especially after moving the stove. It was the 1400 also.
 
The manual for that stove says to leave the door open about an inch until all of the kindling is burning well. And then to only load on a hot coal bed for a good fire. If you are not burning with the top down method then closing the door too soon is gonna croak a fire. I don't care what stove you have.
 
Well I let it burn for probably an hour until I had a good hot fire. I then went ahead and closed the doors but just like before, the flames stopped roaring and the fire looked like it was struggling for air. Moving the damper in and out has no visible effect on how it burns, crack the door though and she instantly comes back to life. I came home later that night to find that the log, which was probably about 4" square was now an ash pile. I guess it did continue smolder down to nothing. The first thing I smelt for was smoke when I went inside and you would never know I had the wood stove going. Also, when I opened the door while it was choking, it never spewed any smoke into the room but had a fair amount of vacuum sucking the smoke out of the chamber.
 
Battenkiller said:
You can't do that with a "laser" thermometer. I know, I know... you can see the laser dot, but the actual area that the internal sensor covers is about 1" in diameter at the very closest you can get to the target. The dot is only a pointing aid and has absolutely nothing to do with taking temps.. Most likely, you were reading only the outer surface.

As far as the laser thermometer goes, I had no idea that's how it worked. I'll definitely look at getting a probe thermometer. I just borrowed the laser to check if I had any "hot spots" around the cathedral box.
 
I would try some different wood, my chimney does not spew any smoke into room ever and fire is kinda crazy with door open, with dry small splits of Green ash and elm I can close the door in 10 to 15 minutes and the fire is fine.
 
north of 60 said:
Is your upper baffle board or brick pushed all the way to the back so you have about a 2.5" opening up front on top?
That was an issue with my mine. Especially after moving the stove. It was the 1400 also.

Those fiber baffles were another concern of mine and are really starting to make me wonder if that's not an issue. I have 10 smaller ones as opposed to two big ones. This was built in 1999 so I attributed the difference in baffles to it's age. The stove can only handle 8 (another thing that concerns me) but even with 8, there would be no gap for air escape. I wish I would have paid attention to how the bricks were installed when I pulled them prior to transport. Anyways, according to the manual, I was supposed to have a minimum 1" gap at the front edge. I cut about an inch and a half off a couple of baffles and put those at the front to give me a 1" clearance. I started thinking after I found that problem, if perhaps the previous owner had only burned it once because it didn't have any place for the gasses to escape. Perhaps he installed the baffling incorrectly. Either way, I'm thinking I'm going to replace the cut baffles that I put at the front edge with the little pieces that I cut off of them. It would increase my air gap to around 2.5". I think I'll try that prior to adding anymore chimney length.
 
BeGreen said:
This sounds like a combo of so-so wood, combined with poor draft. If outside temps are also mild, the short stack probably can't draw well enough. The best way to figure this out is to eliminate unknown variables. Take a planned approach.
1) make sure the air control is open (all the way out)
2) start a fire with dry kindling. Get some carpentry or cabinetry scraps and use them to get the stove going well
3) open a nearby window about 1" and leave the stove door cracked open about 1/2"
4) once the kindling fire is burning well, put on a couple 2x4 scraps, let them get burning well
5) then put on the splits of dry wood, allowing an air gap between them
6) once the fire is fully involved and burning strongly, close the door on the stove.

If this fails, the next thing is to make sure there are no obstructions in the flue and the cap screen is clean. If all the above fail, the stove has insufficient draft. It will need more pipe. To check this theory, get a *temporary* 3 or 4' length of inexpensive galvanized 6" heating vent pipe from the big box store. Pull the cap on the chimney, then cram the venting pipe, crimp down into the chimney. Leave the cap off and try lighting a fire with this temporary extension. If the stove lights up well, try closing the window, after the fire is fully engaged and the stovetop is over 300. If the flame dies back, it will also need an OAK.

Getting more stove length for trial won't be a big deal. My brother is installing his Lopi in the next few weeks and he'd buy any length of pipe that I don't need. I will plan to use some 2x4 scraps for my next fire though to eliminate the wood being the issue.
 
Ya... normal steps in this situation seem to be:
-open a door/window to reduce negative pressure in house (you've done this)
-warm up the chimney (you've done this)
-ensure adequate draft (sounds like a decent draft to me... trying another 3' of chimney might help).

But the fact that you need to open a door/window to improve the draft tells me you've got enough suction coming from the chimney. I'm leaning more towards some sort of defect related to the air control. The fact that there is no perceivable difference between open and closed seems to indicate a problem with the stove.

It also looks like once you get the air control issue resolved, you might need an OAK for the stove. But I would be tearing that stove apart to figure out why the air isn't getting in there, before I tried adding any more air (OAK).
 
I think Pagey is on the right track with flue height being your draft issue. It's hard to put all the math together without a good picture of your setup. You said you had 11' of pipe, so what is the total stack height from ground level? And it goes 2' above the peak of the roof. How high is that roof peak from the ground, and is it the highest part of your full structure or is there a higher roof peak nearby (if so, how high and how far away)?
 
branchburner said:
I think Pagey is on the right track with flue height being your draft issue. It's hard to put all the math together without a good picture of your setup. You said you had 11' of pipe, so what is the total stack height from ground level? And it goes 2' above the peak of the roof. How high is that roof peak from the ground, and is it the highest part of your full structure or is there a higher roof peak nearby (if so, how high and how far away)?

My home is a cape cod style (or a 1 1/2 story as some call it) but with a full two story on the backside making it a 1 3/4 story. Picture a 12/12 pitch on the front going up to the center peak and then sloping down the back side at a 4/12 pitch. The dining room is an extension in the middle of the home with a cathedral ceiling and a 6/12 pitch roof. The stove is in the back corner of the room. The chimney is approximately 15' from the backside of the house and it's second story which is just shy of 10' taller. I understood when I put the chimney in that there would be a risk of low draft but from all the reading I did and talking to others, I felt it would still function as intended and took the risk. I am still wondering if I even have a draft issue but am still planning to at least try a second length of chimney. I'm confused on why my fire sucks in air so hard when I open the door if I didn't have draft. I have ABSOLUTELY no smoke spillage into the room when I open the door like I'd think I would if I had a back draft going. Not sure but either way I plan to try another length of chimney. Like I said, if it doesn't help, I'm not out anything because my brother will buy it. Don't see it hurting anything to try at least.
 
You seem to have a better draft than some that complain of smoke spillage, your chimney draws like mine it sounds like, the dry wood is easier to try or have you ruled that out already?
 
No, I left my pile of wood to try over to my parents but. . . . a little update from a previous post. I'm currently burning the stove (same wood as before) but went ahead and switched out the top baffles for the shorter pieces. It seems to have helped significantly. Not sure if it's a cure all but I've got the door locked shut, the damper set about 2/3 open and a fire that's burning like I had envisioned. It's certainly not a roaring fire, like it is when I crack the door, but a nice hot fire just the same. I am seeing a little difference when adjusting the damper but not much. It basically goes from decent fire to dwindling but not quite dieing. I guess I figured with the damper open, that the fire would be just as hot as if I had the door cracked, or at least get so hot that I would have it over firing, I don't see that happening with what I've got now. Maybe the better seasoned wood would help. I plan to still add the extra chimney length but still not sure if it's my problem. I wish I knew how this stove should act in ideal conditions. Never dealt with a stove that has a damper control so I don't know what kind of difference I should see between full closed and full open.
 
I think you have a couple issues that combined are giving you a hard time.

The reason why your getting good flame when you crack the door is its unrestricted airflow from around the door. The air coming from you primary air control is much smaller and zig zages in the stove. it does sound like you could use some more chimney but since you don't have any smoke back this is my suggestion.

get a hardwood pallet that has been indoors for a while and cut that thing up. (i usually use the sticks and small splinters from splitting to start a fire but using a pallet is much better for starting)

start the fire like you have, and after the fire is roaring with the door open, close it but just leave it cracked and study the fire. at this point the fire shrinks a little but intensifies because of the velocity of the intake air. let the fire come to an equilibrium (not getting larger or dieing out) and close the door completely (air control should be wide open). Now let the fire burn for a few mins and dont panic when it slows down and looks like it dying out. what its doing is now trying to draw the air through the primary inlet, and it changes the burn behavior. Usually after 5 mins or so it will start coming back to life. If it does not I would repeat the process again and try to let the stove get some more heat in it.

What your really trying to do here is learn the stoves starting habits.

over the last winter i have learned how to start my stuff and read the trouble signs and adjust my habits.

when lighting the initial pipe warming I feel as if the paper is not burning well I open a window, but only on the northeast side of the house (pressure side of the wind)

if the fire dies out after shutting the door I will open it back up and throw some more kindling on and let it get a little hotter before trying again.

Also before my first reload I like to crack the door first for about 30sec. If I don't do this I sometimes get a little smoke back into the room.

Again every stove/house combination is different and Its going to take some time to get the best technique for your situation.

Also Fire requires 4 things
Air, Fuel, Ignition, and HEAT. yes it needs heat. So the hotter that stove gets the better the fire will be.
 
skidud said:
No, I left my pile of wood to try over to my parents but. . . . a little update from a previous post. I'm currently burning the stove (same wood as before) but went ahead and switched out the top baffles for the shorter pieces. It seems to have helped significantly. Not sure if it's a cure all but I've got the door locked shut, the damper set about 2/3 open and a fire that's burning like I had envisioned. It's certainly not a roaring fire, like it is when I crack the door, but a nice hot fire just the same. I am seeing a little difference when adjusting the damper but not much. It basically goes from decent fire to dwindling but not quite dieing. I guess I figured with the damper open, that the fire would be just as hot as if I had the door cracked, or at least get so hot that I would have it over firing, I don't see that happening with what I've got now. Maybe the better seasoned wood would help. I plan to still add the extra chimney length but still not sure if it's my problem. I wish I knew how this stove should act in ideal conditions. Never dealt with a stove that has a damper control so I don't know what kind of difference I should see between full closed and full open.

I am glad it helped you with a positive difference.
 
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