Flue damper, what's it for?

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nothing really changed
Is this with the air all the way down or little up like we talked about before? This is replying to post 117.

Keep thinking about what you're doing with the control while you watch the fire and see what each change does throughout a large portion of the cycle to see if the secondaries are still firing or are still extinguishing as before. You said before that they only stay lit 1/4 to 1/2 of the cycle.Let the fire get hot enough that the secondaries are burning well for maybe 5 minutes. Then nurse the control down a little at a time to watch the change in behavior. it sounds like an air supply problem of some kind.We need to determine why. Note the position of the window and if the panels are all on or off, etc. when you do all this. Figure out what it takes to keep the fire hot enough for the secondaries to stay firing.

That may take some patience and time and don't forget about the potential of a negative house pressure that may be changing from time to time causing the fire to be unstable throughout a burn.
 
Is this with the air all the way down or little up like we talked about before? This is replying to post 117.

Keep thinking about what you're doing with the control while you watch the fire and see what each change does throughout a large portion of the cycle to see if the secondaries are still firing or are still extinguishing as before. You said before that they only stay lit 1/4 to 1/2 of the cycle.Let the fire get hot enough that the secondaries are burning well for maybe 5 minutes. Then nurse the control down a little at a time to watch the change in behavior. it sounds like an air supply problem of some kind.We need to determine why. Note the position of the window and if the panels are all on or off, etc. when you do all this. Figure out what it takes to keep the fire hot enough for the secondaries to stay firing.

That may take some patience and time and don't forget about the potential of a negative house pressure that may be changing from time to time causing the fire to be unstable throughout a burn.
the air was down at the time, and i closed the window with no change. I must retire for the evening but i will investigate more tomorrow. Are you thinking its still getting to much air or to little? I do find that even if secondaries arent burning, the longest burn i can get is 3 hours. Regardless of load size. Hell, i may be repeating myself now, I'm so tired. Thanks for all your help, you folks are the true mvps
 
The IR would work too but if you have a surface temp of only 134 on the exterior of the flue liner (uninsulated?) I'd say you're way under-firing the stove. My stovepipe thermometer, which supposedly measures surface temp of the stovepipe, reads 325-400 when I've set the air for the evening.
 
Just for chuckles I went down and checked mine with the IR and the stovepipe thermo is within 20* of IR. I have a full bed of hot coals, no active flame, so the stove is about ready to reload and the top of the stove registers at 308, stovepipe at 200 and door frame is 300. This is our primary heat so it gets a workout. I had the gas shut off 2 years ago because I got tired of paying 20 bucks a month just to be a customer. When it gets really cold we have a couple ceramic heaters for upstairs.
 
the air was down at the time, and i closed the window with no change. I must retire for the evening but i will investigate more tomorrow. Are you thinking its still getting to much air or to little? I do find that even if secondaries arent burning, the longest burn i can get is 3 hours. Regardless of load size. Hell, i may be repeating myself now, I'm so tired. Thanks for all your help, you folks are the true mvps
There doesn't seem to be a lot of info here about these stoves, but you may want to read through this one to learn a little more about others' experiences with it:
https://www.hearth.com/talk/threads/buck-stove-model-94nc.144058/
 
Alright, I think I may of discovered another issue maybe? The front of the stove is showing about 575* on the magnetic thermo, and my IR gun. However, the air coming out of the blower vents is only showing me its 191*....

Also, I still don't think there is much of an issue with the chimney. I could be wrong, but i stated before that the previous home owner had knocked some of the chimney down, and installed a concrete cap. My stove installer busted an 8 inch hole in it for the ss pipe to fit into. I could be wrong, but I feel 0 air movement behind the stove.

Don't get too caught up on your IR temps of the stove with the fans on and air blowing across the surface. The air has a significant cooling effect on the surface temp. If you want to check the surface temp you need to turn the fans off and let it heat up before you check it. The face if the stove will be hotter because it doesn't have air blowing over it. If you leave the fans off for a while I'd expect the stove top to resemble the stove face more closely.

Now, you showed us a great pic of the top of the stove and the flue connector pipe when you removed the center panel of the trim. Reach back in there close to the stove pipe with your cell phone pointing up the chimney and take a picture so we can see if you have a block off plate or not. Even if thst chimney is "capped" with brick and mortar at 8', if you do not have a block off plate then the volume of air in the chimney space is acting as a heat sink, as well as all that masonry. It will rob the heat from the stove.
 
So based on that closing the window didn’t change the state of the fire, I’m not convinced air supply is a problem.

At this time, it sounds to me that it could be as simple as shutting the air down too fast and/or too early.

How are you measuring the air temp coming off the insert?

I’ll take a step back here, how are you defining your burn time?
 
So based on that closing the window didn’t change the state of the fire, I’m not convinced air supply is a problem.

At this time, it sounds to me that it could be as simple as shutting the air down too fast and/or too early.

How are you measuring the air temp coming off the insert?

I’ll take a step back here, how are you defining your burn time?


I'm still there myself. It sounds like it's not getting enough time to come up to temp before cutting the air back and he's getting a low temp, slow lazy fire and the stove just isn't getting hot enough.
 
So based on that closing the window didn’t change the state of the fire, I’m not convinced air supply is a problem.

At this time, it sounds to me that it could be as simple as shutting the air down too fast and/or too early.

How are you measuring the air temp coming off the insert?

I’ll take a step back here, how are you defining your burn time?
I have a magnetic thermo and an iR gun. I define burn time from the time i put wood in to the tine its turned into nothing but coals
 
Don't get too caught up on your IR temps of the stove with the fans on and air blowing across the surface. The air has a significant cooling effect on the surface temp. If you want to check the surface temp you need to turn the fans off and let it heat up before you check it. The face if the stove will be hotter because it doesn't have air blowing over it. If you leave the fans off for a while I'd expect the stove top to resemble the stove face more closely.

Now, you showed us a great pic of the top of the stove and the flue connector pipe when you removed the center panel of the trim. Reach back in there close to the stove pipe with your cell phone pointing up the chimney and take a picture so we can see if you have a block off plate or not. Even if thst chimney is "capped" with brick and mortar at 8', if you do not have a block off plate then the volume of air in the chimney space is acting as a heat sink, as well as all that masonry. It will rob the heat from the stove.
I will get you that photo tonight when im home
 
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I have a magnetic thermo and an iR gun. I define burn time from the time i put wood in to the tine its turned into nothing but coals

Ok, so when you get the fire going tonight, say 30 minutes into the burn and after you've set the air for the evening, take the IR and with the center panel off aim 2-3 feet above the insert, or as high as you can see whichever is greater, and see what the reading is on the liner.
 
I have a magnetic thermo and an iR gun. I define burn time from the time i put wood in to the tine its turned into nothing but coals

I only ask because IR tools don’t measure air temperature, they measure surface temperatures.

You mentioned earlier that you’ll only put in 4 splits, would say that’s a normal load for you? For a stove as large as yours, that’s not a whole lot. Mine’s 2.3 ft^3 and 4 is my bare minimum and that hardly happens.
 
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I only ask because IR tools don’t measure air temperature, they measure surface temperatures.

You mentioned earlier that you’ll only put in 4 splits, would say that’s a normal load for you? For a stove as large as yours, that’s not a whole lot. Mine’s 2.3 ft^3 and 4 is my bare minimum and that hardly happens.
Yeah sometimes, maybe that's my problem lol
 
Here's a shot up the chimney
 

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Ok, so when you get the fire going tonight, say 30 minutes into the burn and after you've set the air for the evening, take the IR and with the center panel off aim 2-3 feet above the insert, or as high as you can see whichever is greater, and see what the reading is on the liner.
Liner 337* stove front is 587*
 
Its pretty full. Not a night load. I'm up for several hours. I just got home from work. Its got 9 pieces in it now, all medium -small
 
I would think at those temps you should have plenty of heat rolling out the front with the blower on for at least a few hours.

These are the conditions you have and you still have no heat from the stove??
 
How warm are your rooms and how warm are you expecting them to be? I saw mid-70s earlier for the stove room, what about the others?

I’d also go around with the IR gun to each room and find the cold spots. That might reveal something as well. Check along the walls at the floor, ceiling and windows. Also any penetrations in the ceiling.
 
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