Lopi insert only burns wood at the front of the stove

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planker101

New Member
Jan 28, 2017
5
California
Hi,
I'm new to the forum. I couldn't find any good info with a google search and have always found forums to be an excellent source of information, hopefully this is an appropriate forum for my question.

I have a Lopi wood stove insert. It works ok, however, when I wake up in the morning it always has a lot of fuel left at the back of the stove that I believe if it had burned during the night would have kept my house closer to my desired temperature.

As far as I can tell there is only one hole for air inlet at the front and center of the stove. One time to do a through cleaning I took the firebricks out and saw two plugs in the back on the bottom (one on each side). Are these possibly another inlet?

If the plugs aren't another inlet is it possible to mod the stove? I am a proficient welder and would be comfortable welding some tubing to the front inlet hole and routing airflow throughout the stove, but it seems like there should be an easier solution.

Any suggestions are appreciated.
Thanks!
 
If wood burns only in front of the stove two things come to mind.
1 wet wood
2 stove chocked too much or 3
3 both
Tell us what kind of stove you running, what kind of wood, how dry is the glass clean or black?
 
Need model and age of the stove. And what temp does it run at? Probably wet wood.
 
Lopi 1750 Republic wood insert that is 3 years old. As far as temp goes I do not have a thermometer on it, but I run it pretty hot until the house warms up, then push the air control rod in to a point where it has just a tiny bit of flame and wood is nice and red (This is approx 1/2" pulled out).
I have burned Oak, Pine, and Almond all with the same results. I only burned seasoned wood. Same results with one year of seasoning or two. My wood storage is on top of pallets and covered.
-Not wet wood, been using a wood burning stove my whole life and know the difference.
Glass is clear in the middle with about 2-3" of black around the edges. About once a month the middle will get dirty and I will clean it.

I always put my wood in with the length of the wood running front to back. If I pull the air flow rod out much more than I do my house gets way to hot, in the mid 80's. Fuels in front half of stove are burnt down to grey ash. Fuels in 3rd quarter of stove usually fown do a mix of black ash and still some red coals. fuels in last quarter are black and have a few hours of burn left after I mix stuff up and put fuels from rear on top of still red coals.

The image in the manual that actually looks like my stove show that when the bypass is closed (which is how the instruction say to run it after it gets going) the air is routed from the top front of the stove through a channel on top of the stove and then up and out. With the air inlet at the front bottom it makes sense to me that the wood in the back would not burn as well since the air would not really be routed to the back. With the bypass open air flow is from front bottom to rear top. This is why I asked about modification to relocated air intake, however, I feel like there *should* be an easier way.
 
To me sounds like you starve the stove for air. Close air in increments. You close air way too much that's the problem. Wood stil might be on the wet side. You should maintain a clean glass. Black glass suggests wet wood or starvation for air.
 
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Are you getting a secondary burn from the tubes when you turn it down?
Im with the above post. The air control is not a direct temp control that you open for more heat and close for less. A good way to know if you're starving it for air is to see if you're sending smoke out the pipe.
 
Seasoned wood to me is wood that got salt on it from the road, dry wood is key, purchase a moisture meter and test a freshly split piece of wood at room temp, it should read 20% or less.
 
It is possible that I am starving it for air, however, with this stove there is a pretty direct heat to air correlation. I have run it with varying air flow and the more airflow the more heat. at about 1.5-2" pulled out my house is hot, like open the windows hot (this is after the fire is going well, I leave it full out for starting fires). Manual reccomends fully pushed in to 1/8" pulled out for overnight burns. I do significantly more than that. As far as moisture goes my stove came with a moisture meter (device with two prongs that you shove in the wood) I don't use it every time I have a fire or anything, but moisture has been well below 20% when I have checked.

Since the concensus seems to be air flow or wet wood, and I am 100% sure it's not wet wood, that leaves airflow. Manual says all the way in to 1/8" out for overnight. I go closer to 1/2", but have tried more. My process is get a good fire going (which to me is all the wood on fire, as opposed to smouldering.) Leave air flow at max until house gets warm, push in about half way until I get to desired house temp of 70-73, then push in about 3/4 of the way to maintain temp. Finally, right before bed push in all the way and pull out about 1/2".
This is the first stove I've had with a bypass and the secondary burn deal. My others have been the ones with a spinning knob on each door for air control. Am I using this stove incorrectly perhaps?
 
Every setup is different. How much you can close the air depends how much draft you get in a certain situation. You don't want to leave it open full then close it when you the house is warm enough. You start your fire, you have nice fire going close it half way. Wait few minutes now try to close it some more. You do it gradually without killing flames completely. Watch what is happening in the fire box. When dry wood is being burned and stove is operated properly glass will stay clean and stove will burn all the wood. Like I said before black glass indicates either wet wood, not enough air or both.
 
14% on freshly split piece of wood (and that was one of my larger pieces so that should be about as high as it gets)
Lopi insert only burns wood at the front of the stove
 
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If wood can be ruled out, I'd say that you're choking the air too much for an overnight burn. We have had a similar insert and run it choked pretty low most of the time, but never as low as the manual suggests is possible. In our set up, that would result in blackened glass and unburnt fuel in the back.

Our inserts are basically the same, and we've got good seasoned wood and a tall, straight chimney. Nevertheless, we cannot close the air control fully or as much as the manual suggests for an overnight burn. When we stoke it later tonight, I'll see if I can measure the distance for you. In our case our stove is in the basement of a pretty well insulated and moderately air sealed house. It's a negative pressure zone. We are careful not to run fans while reloading, but we figure that we have to allow the stove to have more air because it's working pretty hard to get it. That being said, it heats our house well, burns clean and leaves us coals (not unburnt wood) in the back for a reload in the morning.

We control our temperatures during the day by the size of the load, the type of wood we burn, or the setting of the blower. We do have to let the stove go out in mild weather with lots of sun. When we do a full load for overnight, it will overheat the basement room, but we sleep upstairs, so that's just what we do. We close down the air in a couple increments, but we always watch after that final adjustment to make sure that there are not only good secondaries at the top of the box but also some good bright flames over the majority of the wood. If we choke it to just glowing wood with little flame, that's too little oxygen for our stove.

Even burning a compressed wood product we can't choke our stove fully down, so it doesn't have to be just a moisture issue. I think the key is to discover what a clean burn looks like on your stove and try not to let the wood smolder. When we were learning our stove, we did lots of checking the chimney to make sure we were burning clean. It takes tweaking so that we don't let things get too hot or too starved. We found that just the tiniest adjustment can make a big difference. We've worked it into being part of our nightly routine that sitting in front of the fire and adjusting is how we wind down after kids are in bed. We enjoy it and spend more time in front of the stove than it requires.

It's probably about time to begin that again. I'll try to take some measurements if I can and post again another time.
 
Who installed the stove and does it have a liner or could the liner have been dislodged or damaged causing loss of draft at lower temps? Sounds odd that some of the wood would burn then stop.
 
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I checked our setting for tonight. It is about half an inch out. It is burning pretty vigorously inside the firebox, but choking it further would give us a dirtier burn, I think. Our glass usually stays pretty clean unless we come across wetter wood in our piles or load some pieces too close to the glass.
 
In the am get the fire going like normal, then once it gets to hot do what you normally do as reducing the air, go outside and look at your chimney after 15min of air adjusting, you should have very little smoke / only heat curves coming out the chimney cap.
Also while your looking at the cap, check for any clogs that could be causing your stove to essentially stall during the burn. Thanks for providing the pic of the wood / moisture meter, like your style.
 
Thanks for the last few responses. I will test/ try the things suggested and see what kind if results I get. I was getting frustrated with the initial repeated insinuations that I was burning wet wood. Nice to get some suggestions I can work with :)
 
I wasn't insisting that your wood is wet. All I was trying to say there is a reason for non complete burn. What you described indicates wet wood. A lot of time folks here think they have a dry wood when the reality is it's marginal or plain wet. I am glad it's not in your case. Try to maintain a bit of yellow (bright) flame, when you burn.
 
Who installed the stove and does it have a liner or could the liner have been dislodged or damaged causing loss of draft at lower temps? Sounds odd that some of the wood would burn then stop.
Yes, can you describe the chimney? Full liner from the stove to the top? Insulated? I'm assuming it's pretty straight if it's installed in a masonry chimney...