Temps (I know, its asked a lot)

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Dec 29, 2020
6
Indiana
First off, I know questions about temperatures have been asked A LOT! I feel I've read them all, yet I'm still uncertain on an answer. So I don't know if I'm just too dense or what, and therefore I thought I'd try with a lot of very specific information in case that might finally help get me over the hump.

Attached is a picture of our wood stove. We purchased the house about 10 months ago. House built in 2008 and all indications are the stove was new at that time. However, I cannot say that with 100% certainty.....what I would call a 95% estimate.

No owners manual to be had. No tags or markings anywhere to know the manufacturer info (would love to find that in order to get an online manual). As you can see, it is surrounded by soapstone (about 3 inches thick). The house itself has tons of higher-end upgrades, materials, etc and many "it was built right" touches throughout. Based on all of that, I find it highly unlikely that the stove is poorly made or a "Chinese knockoff" as is referenced at times. Oh, former owner and who had the home built is a career firefighter, so further makes me think it is a well-built stove. Outside of finding a specific brand, the only other possibility I can think of is maybe Amish-built as there are a number of Amish communities within a reasonable distance of our location.

Here are all of the details I can think of that could be relevant to the conversation:
  1. quality of stove as mentioned above, but unable to get firm confirmation on brand info or age.
  2. No fan or automated damper, etc. Airflow is controlled manually by the two "silver" vents/knobs on the front of the stove.
  3. only 1 bend in the stovepipe, which is a 30 or 45 degree almost immediately after the stove and then again to where it turns vertical. From there, is straight up all the way to the chimney cap.
  4. surrounded by 3" soapstone.
  5. double-wall stovepipe from stove to ceiling. I haven't taken a true measurement, but eyeballing it I would say the external diameter is 8" or even 10".
  6. chimney pipe we had replaced with new stainless, installed by national industry expert (if I gave description, it would be very easy to identify is name/info and I don't want to do that without his permission), told it was top of the line in terms of material, manufacturing, etc. It is stainless, I recall he said rated to 2100 degrees, etc. I've not gotten on the roof to get an exact measurement, but I'd estimate it to be 18 or 20 feet tall and is "inside" a framed chimney chase (not lined, but wood-framed to hold cement fiber siding...and there is LOTS of clearance space between the pipe and the chase framing). Why did we have new chimney pipe installed? Not out of necessity, but rather peace of mind knowing it was new, done right, etc because there is no way to truly know how frequently the prior owners had it cleaned (even though visual inspection showed it was fine/clean). In short, probably completely unnecessary but worth the price for comfort of mind in my book.
  7. also had new chase cover and pipe cap installed when the new chimney pipe was installed.

So I'm trying to figure out some info to give me comfort in terms of heating the house well, but calm any nerves in terms of risk of chimney fire.

We do NOT have a temperature probe in the flue. We do NOT have a temperature gun (probably need to get one, though). All I have are two of the cheap magnetic thermometers normally used on the outside of the stovepipe. However, knowing it is double-wall stovepipe, I don't figure it does me a lot of good to put it on the pipe anyway, right?
So, I've stuck them on the stove itself. One is on the front in the top corner (you can probably see it in the pic) and the other is on the top of the stove right next to where the stovepipe is attached.
But, I realize they are just points of reference. First, they are just magnetic and I know they aren't all that accurate to start with. Second, I know from reading other threads the surface temps can vary greatly over the course of just a few inches. So although they are a point of reference, that is about the best purpose they serve.

With that said, when I look at the one on the front of the stove, it is usually fluctuating in the 300-450 degree range depending on the stage of the fire and placement of the logs. The one on top of the stove, near the stove pipe, is usually reading in the 600-700 degree range. But when the flames are going (instead of just hot coals), the flames can touch the surface of the stove so I know that contributes to the higher readout and is temporary in nature.

I've tried the visual, which is to go outside and look for any smoke. I'd say usually, there is none or very little (of course, the exception to that is when getting a new fire going and up to temp). So that seems to be a good sign.

Overall, I question if we might be burning too hot continuously. I know smaller, hotter fires are desired. And, something to be said for establishing some nice hot coals and they do most of the heating. But I feel like the temps drop off significantly, and the warmth in the room drops as well, if there isn't at least some degree of an active fire going. So we do load a log every hour or two, depending on its size. But I wonder if we're not also losing too much heat up the stovepipe rather than truly heating the room. On the other hand, if we close the air supply down, that buys some time (longer burn), but it does seem to stifle the fire as well almost too much (meaning sometimes, the temps still drop off and opening the door it is smoking more than anything, which makes me worry about creosote, so I increase the air supply again).

I just feel like I'm constantly fighting to find the right balance. What feels warmest and most natural seems like maybe too fast of a burn and therefore maybe wasting too much heat up the chimney. But if I try to control that aspect at all, even a slight adjustment, then it seems to choke the fire too much to where there isn't a comfortable heat and I wonder about creosote...especially given the total length of stove/chimney pipe and our winter temps usually in the teens to thirties. And, to go with all of that, I also wonder if our flue gas temps may be too high, even though there is no current sign of strain and my only point of reference for temps are the cheap magnets. I've read some threads that indicate the stove temp is going to be lower than the flue gasses, so if that cheap magnet is anywhere close to being accurate at say 600 degrees, could that mean my flue gas temp is 800, 900, or higher???

I'm a rookie at this. I grew up on a regular fireplace, not a wood stove. My wife grew up on wood stove and/or wood burning furnaces, but they had automatic thermostats, blowers, and dampers. So none of that completely translates to our use. I'm not overly concerned with it while we are in the room, but we're trying to use it overnight as well and to some degree it is obviously burning when we leave for the store, eat, or run other errands. I'm trying to reach a higher degree of comfort, mostly for those unattended or overnight situations. And that is where no matter how much reading and research I do, I seem to have more questions than answers and comfort.

Any words of wisdom from this group would be greatly appreciated in terms of whether or not our temps seem "ok" or too high/low, what else to look for, and if by some slight chance anyone has a guess on the brand based on this single picture? Thank you so much, all! The other threads I've read through have been very informative, and I look forward to learning more from your experience and wisdom. Thanks again!

stove.jpeg
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,564
central pa
First off, I know questions about temperatures have been asked A LOT! I feel I've read them all, yet I'm still uncertain on an answer. So I don't know if I'm just too dense or what, and therefore I thought I'd try with a lot of very specific information in case that might finally help get me over the hump.

Attached is a picture of our wood stove. We purchased the house about 10 months ago. House built in 2008 and all indications are the stove was new at that time. However, I cannot say that with 100% certainty.....what I would call a 95% estimate.

No owners manual to be had. No tags or markings anywhere to know the manufacturer info (would love to find that in order to get an online manual). As you can see, it is surrounded by soapstone (about 3 inches thick). The house itself has tons of higher-end upgrades, materials, etc and many "it was built right" touches throughout. Based on all of that, I find it highly unlikely that the stove is poorly made or a "Chinese knockoff" as is referenced at times. Oh, former owner and who had the home built is a career firefighter, so further makes me think it is a well-built stove. Outside of finding a specific brand, the only other possibility I can think of is maybe Amish-built as there are a number of Amish communities within a reasonable distance of our location.

Here are all of the details I can think of that could be relevant to the conversation:
  1. quality of stove as mentioned above, but unable to get firm confirmation on brand info or age.
  2. No fan or automated damper, etc. Airflow is controlled manually by the two "silver" vents/knobs on the front of the stove.
  3. only 1 bend in the stovepipe, which is a 30 or 45 degree almost immediately after the stove and then again to where it turns vertical. From there, is straight up all the way to the chimney cap.
  4. surrounded by 3" soapstone.
  5. double-wall stovepipe from stove to ceiling. I haven't taken a true measurement, but eyeballing it I would say the external diameter is 8" or even 10".
  6. chimney pipe we had replaced with new stainless, installed by national industry expert (if I gave description, it would be very easy to identify is name/info and I don't want to do that without his permission), told it was top of the line in terms of material, manufacturing, etc. It is stainless, I recall he said rated to 2100 degrees, etc. I've not gotten on the roof to get an exact measurement, but I'd estimate it to be 18 or 20 feet tall and is "inside" a framed chimney chase (not lined, but wood-framed to hold cement fiber siding...and there is LOTS of clearance space between the pipe and the chase framing). Why did we have new chimney pipe installed? Not out of necessity, but rather peace of mind knowing it was new, done right, etc because there is no way to truly know how frequently the prior owners had it cleaned (even though visual inspection showed it was fine/clean). In short, probably completely unnecessary but worth the price for comfort of mind in my book.
  7. also had new chase cover and pipe cap installed when the new chimney pipe was installed.

So I'm trying to figure out some info to give me comfort in terms of heating the house well, but calm any nerves in terms of risk of chimney fire.

We do NOT have a temperature probe in the flue. We do NOT have a temperature gun (probably need to get one, though). All I have are two of the cheap magnetic thermometers normally used on the outside of the stovepipe. However, knowing it is double-wall stovepipe, I don't figure it does me a lot of good to put it on the pipe anyway, right?
So, I've stuck them on the stove itself. One is on the front in the top corner (you can probably see it in the pic) and the other is on the top of the stove right next to where the stovepipe is attached.
But, I realize they are just points of reference. First, they are just magnetic and I know they aren't all that accurate to start with. Second, I know from reading other threads the surface temps can vary greatly over the course of just a few inches. So although they are a point of reference, that is about the best purpose they serve.

With that said, when I look at the one on the front of the stove, it is usually fluctuating in the 300-450 degree range depending on the stage of the fire and placement of the logs. The one on top of the stove, near the stove pipe, is usually reading in the 600-700 degree range. But when the flames are going (instead of just hot coals), the flames can touch the surface of the stove so I know that contributes to the higher readout and is temporary in nature.

I've tried the visual, which is to go outside and look for any smoke. I'd say usually, there is none or very little (of course, the exception to that is when getting a new fire going and up to temp). So that seems to be a good sign.

Overall, I question if we might be burning too hot continuously. I know smaller, hotter fires are desired. And, something to be said for establishing some nice hot coals and they do most of the heating. But I feel like the temps drop off significantly, and the warmth in the room drops as well, if there isn't at least some degree of an active fire going. So we do load a log every hour or two, depending on its size. But I wonder if we're not also losing too much heat up the stovepipe rather than truly heating the room. On the other hand, if we close the air supply down, that buys some time (longer burn), but it does seem to stifle the fire as well almost too much (meaning sometimes, the temps still drop off and opening the door it is smoking more than anything, which makes me worry about creosote, so I increase the air supply again).

I just feel like I'm constantly fighting to find the right balance. What feels warmest and most natural seems like maybe too fast of a burn and therefore maybe wasting too much heat up the chimney. But if I try to control that aspect at all, even a slight adjustment, then it seems to choke the fire too much to where there isn't a comfortable heat and I wonder about creosote...especially given the total length of stove/chimney pipe and our winter temps usually in the teens to thirties. And, to go with all of that, I also wonder if our flue gas temps may be too high, even though there is no current sign of strain and my only point of reference for temps are the cheap magnets. I've read some threads that indicate the stove temp is going to be lower than the flue gasses, so if that cheap magnet is anywhere close to being accurate at say 600 degrees, could that mean my flue gas temp is 800, 900, or higher???

I'm a rookie at this. I grew up on a regular fireplace, not a wood stove. My wife grew up on wood stove and/or wood burning furnaces, but they had automatic thermostats, blowers, and dampers. So none of that completely translates to our use. I'm not overly concerned with it while we are in the room, but we're trying to use it overnight as well and to some degree it is obviously burning when we leave for the store, eat, or run other errands. I'm trying to reach a higher degree of comfort, mostly for those unattended or overnight situations. And that is where no matter how much reading and research I do, I seem to have more questions than answers and comfort.

Any words of wisdom from this group would be greatly appreciated in terms of whether or not our temps seem "ok" or too high/low, what else to look for, and if by some slight chance anyone has a guess on the brand based on this single picture? Thank you so much, all! The other threads I've read through have been very informative, and I look forward to learning more from your experience and wisdom. Thanks again!

View attachment 270678
Did you ask the industry expert what stove it was?

It doesn't look like a tulikivi Stove to me but possibly. Possibly one of the vermont bun baker stoves.
 
Dec 29, 2020
6
Indiana
Yes, I asked and he looked all over for markings and also unable to determine. So if there are any tags, they have to be blocked by the soapstone.
I do know it is not a Vermont Bake Oven, as I've sent them a pic and they've replied confirming none of their models over the years looked like this.


I also realized I forgot to include in the original post the wood we burn is well-seasoned (minimum of 2 years in all cases, and always stored under an open-sided but roofed series of wood sheds) and mostly maple and ash.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,638
South Puget Sound, WA
600º on the stovepipe is hot. How tall is the flue system from stove to chimney cap? Is the stovepipe single-wall? Is there a key damper in the stovepipe?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,564
central pa
Yes, I asked and he looked all over for markings and also unable to determine. So if there are any tags, they have to be blocked by the soapstone.
I do know it is not a Vermont Bake Oven, as I've sent them a pic and they've replied confirming none of their models over the years looked like this.


I also realized I forgot to include in the original post the wood we burn is well-seasoned (minimum of 2 years in all cases, and always stored under an open-sided but roofed series of wood sheds) and mostly maple and ash.
I would check with tulikivi
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,638
South Puget Sound, WA
I am pretty sure the Vermont Bun is made by Nectre in Australia. It might be asking if this is an earlier variant of their stove.

Also check with Obidiah's. They have a long history with wood cookstoves.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,638
South Puget Sound, WA
Dec 29, 2020
6
Indiana
Thanks, all. I'll do some further checking with those possible manufacturers!

begreen - from the stove to the ceiling is 6-7 feet, and then the chimney outside is another 18-20. So stove to cap, we're talking a good 25 feet or more. The stovepipe (inside the house) is double-wall. There is no damper other than the one at the top of the stove itself, which can't be varied....it is either 100% open or 100% closed.
When you say 600 at the stove is hot, what would you call "ideal" (knowing every stove is different, and we're not sure what this one is)? And again, that is just based on a $5 magnetic dial thermometer, so take that reading for what it is worth.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,638
South Puget Sound, WA
When you say 600 at the stove is hot, what would you call "ideal" (knowing every stove is different, and we're not sure what this one is)? And again, that is just based on a $5 magnetic dial thermometer, so take that reading for what it is worth.
I thought you were reporting the temperature on the stovepipe in the earlier posting, not the stovetop. 600º stovetop temp is fine. 600º stovepipe temp is a different thing entirely. Actually, it looks like your thermometer is on the stove face. Stove face temp is not the same as flue gas temp. You will need a probe thermometer to read that in double-wall stove pipe. The flue is a bit tall and may benefit from a key damper section added to the stove pipe.
 
Dec 29, 2020
6
Indiana
begreen - thank you for the link to Grand Cook Stove. I have a message in to them to see if they can/will confirm, but everything does seem to match up. The dimensions listed, the design even down to the individual elements like handles, etc all appear to match. The only difference I can find is the handle on top for the damper - ours is on the opposite side of the stovepipe. The fact the site says Amish-made and that the site shows they are out of Michigan all even lines up with possibilities. So thank you very much for that lead!


Your comment that 600 on the stovetop is fine makes me feel better. It can spike to 700 or so after loading a fresh log in if it really takes off, but that is only for a very short time. I'm curious, then...if 600 is an accurate reading on the stovetop, what might you guess the internal flue gas temps could be? One of these days, I will get a laser thermometer and then perhaps in the off-season when we have it swept, look into a flue probe as well. But until then, I'm curious how much the flue gas temps can vary from the stove's surface temps (haven't run across that info yet in any reading).
 
Dec 29, 2020
6
Indiana
MYSTERY SOLVED! - begreen is correct, it is a Grand Cook Stove. They responded to my email and confirmed indeed it is one of their models. Thank you!!!

With that, they sent an owners manual. It is only a few pages long, most of which deals with installation rather than operation. Some of the other threads I've read seam to suggest the owners manuals usually give info regarding temperature targets or limits, etc. This manual does not, other than to say if the stove or the stovepipe connector begins to glow, you are too hot (seems obvious, even to this rookie).
But if I'm reading things correctly, it appears I should only have the damper to the flue pipe open when I'm going to open the front loading door. During operation, it appears the damper should be closed.
The stove is relatively simple in design - 2 air inlets on the door, the door itself, and the damper. No other levers or controls, no blower, etc.
Could I be interpreting that correctly? Is it reasonable to keep the damper closed during operation of a woodstove? It certainly would help with the heat, likely explains why I'm loading a new log every 1-2 hours, etc. I also think about the fact our house is nearly 4,000 sq ft and the prior owners used the stove as their primary heat source...yet for us, the best we can get the room it is installed in is the mid to upper 60's. So it all seems to make sense - we were sending our heat right up the chimney. But if all of that is true and we now keep the damper closed other than a brief period to load a fresh piece of wood, where does all of the "smoke" (exhaust) go while it is burning?

I think if I can wrap my head around that question, this rookie may have all sorts of light bulbs go off in his brain!
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,638
South Puget Sound, WA
That's great that they responded quickly and that you now have an ID. Did they do the soapstone too?

When talking about temps on this stove we are talking stove face temps because the stovetop is covered by the soapstone slab. Do you always engage the oven bypass once the stove is hot?

It's doubtful that this stove, or any one stove, would heat the house well in the dead of winter in Indiana. 4000sq ft is a huge home and Indiana can get some very cold temps when a polar express descends on the state. If the goal is to heat the home with wood, then it is going to require a lot more firepower.
 
Dec 29, 2020
6
Indiana
That's great that they responded quickly and that you now have an ID. Did they do the soapstone too?

They do not do the soapstone. My guess is you are correct it was a custom-build, very likely the prior homeowner. It would explain a couple of spare pieces we found in the pole barn next to an old rusted antique stove. I never thought much about it, as it appeared they were cutting pieces to try to refurbish that old one. If nothing else, it does show they had the material and could cut it, etc. So can't confirm, but definitely makes it a strong possibility.


When talking about temps on this stove we are talking stove face temps because the stovetop is covered by the soapstone slab. Do you always engage the oven bypass once the stove is hot?

It's doubtful that this stove, or any one stove, would heat the house well in the dead of winter in Indiana. 4000sq ft is a huge home and Indiana can get some very cold temps when a polar express descends on the state. If the goal is to heat the home with wood, then it is going to require a lot more firepower.


Until today's confirmation, we'd never "engaged the oven bypass" in the manner you are probably asking. What I mean is I had no idea it was an oven bypass. I just thought it was the damper and had to be open in order to allow the fire to burn and exhaust up the chimney! I had no idea it could be closed and the stove still function. In fact, I still didn't know that from the owner's manual...which is why I asked the additional question. But since posting that, I found a random YouTube video not from the manufacturer, but a person that bought one and they happened to describe how closing that circulated the air/exhaust down to and around the baking oven, and then still flow up behind the damper in the firebox and therefore still exhausts up the chimney. So that helped seeing/hearing that. As noted in my original post, my only real point of reference is a traditional fireplace and you'd never have the damper closed or else the house would fill with smoke and fumes quickly.
Knowing one can "close" the damper (it was a damper to me, but oven bypass to you all) and it function fine and properly is one of those complete unknowns to a newbie but 2nd nature to all of you. Thank you for sharing that wisdom and helping me understand the design of these things!

As for the heating of the space, that is probably a little misleading. A portion of that 4,000 is a basement area and I would not expect the stove to heat that space. Above grade is more in the 2,500-2,800 range I would estimate. Still a lot of space for a relatively small stove, but we visited the house a few times between Christmas and mid-February when we were going through the purchase process. Every time, the house was nice and toasty throughout...far warmer than we've been able to achieve (and now know why - we were sending most of our heat right up the chimney).
 

WoodScrounger

New Member
Oct 11, 2020
48
Ontario
But if I'm reading things correctly, it appears I should only have the damper to the flue pipe open when I'm going to open the front loading door. During operation, it appears the damper should be closed.
Could I be interpreting that correctly? Is it reasonable to keep the damper closed during operation of a woodstove? It certainly would help with the heat, likely explains why I'm loading a new log every 1-2 hours, etc.
I grew up with a different stove than this but it sounds similar in configuration. On that stove the damper control in the top was like a baffle bypass, opened straight up the chimney. When it was closed the smoke/heat had to go around a baffle system which was a bit more constricted. We were only supposed to open it to load the stove and we used a draft control that was in the bottom to control the burn.
I remember getting yelled at :rolleyes:for forgetting to shut the damper as it tended to over fire the stove and wasted fuel.