How hot do you burn your Jotul?

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I have the 550 insert and it likes to cruise in the upper 500's to the upper 600's. It usually gets into the 700's every few days for awhile and handles it just fine. My comfort range is in the 600's.
 
I get our Oslo up to 500-550 to start then let her settle somewhere around 400, give or take. Im sure as it progressively gets colder out I'll increase these numbers, but she's been doing her job just fine. Did I mention I love this stove?
 
xman23 said:
In north east PA mountains it's a winter wonderland 6 inches so far and snowing hard now. The oslo has been crusing for it's first 24 hrs this year. Stove top tempi is 325, stack is 280. Going down to 20's tonight. I love it, This is what it's all aboit.

Those numbers seem a bit low . . . are you getting secondary combustion with the Oslo at that low temp? Also, at that low a temp on the flue there is a good chance you will be producing some creosote.
 
nelraq said:
I'm confused! Most of the posts above refer to "running" the stove at 400, 450, 550, 650 etc. What do you mean by "run?" Yes . . . by "run" or "cruise" folks are talking about what temps they tend to have their woodstove running at . . . which generally is reached by getting the woodstove to that point or a point slightly below that temp.

Are you talking about getting the stove up to 650; then maintaining the 650 burn temp. for several hours after that. How can you do this? Here's what works for me . . . After getting a fire established with a good bed of coals I'll place my small to medium splits on the coals and open up the air. This has the result of increasing the flue temp and the stove top temp to a certain degree. Once the flue temp is above the creosote producing stage and/or the wood is coaling nicely and/or the stove top temp is around 400-450 degrees I'll start to cut back on the air . . . and what generally happens is the secondary combustion starts . . . and then the magic really starts as the flue temp drops a bit and the stove top temp starts to rise a bit . . . and typically I can hear some clicking and ticking as the stove begins to really throw off the heat. If the stove gets up to 650, will it not continue to rise unless you restrict the air - and if you restrict the air does the stove not fairly quickly start losing temp? Actually, it's just the opposite . . . once you're at the temp high enough for secondary combustion and you start to cut back the air you will find that as you start reducing the amount of air you will get fewer flames and more secondary combustion (i.e. look for the Northern Lights or Bowels of Hell) and the firebox temp will actually increase. Or do you add more splits every so often during the burn cycle? There are only two times when I add splits: when the wood has gone to the late coaling stage or occasionally when I'm doing a cold start and the fire is established, but it is still pretty small as most of the kindling has burned up . . . what I never do is attempt to add wood when I'm seeing any signs of secondary combustion.

Alternately, when you say that you run your stove at 650, does this mean that you get the stove up to 650 then shut the air down? ie. you run the stove up to 650, then let it cool down gradually to 2 or 300 degrees then fill the stove and let it run up to 650 again? Well kind of . . . I actually prefer to let my stove run up to 450-500 on the stove top before starting to cut back the air. I also like to make sure the wood is good and charred (it typically is at this point) and I like to make sure the flue temp is above the creosote producing stage . . . I start by cutting the air back to the halfway point . . . monitor the temp and fire for 5-10 minutes and then cut it back to the 1/4 mark . . . again watch the temps and fire (usually at this point the stove is starting to make the ticking noises and the stove top temp begins climbing . . . flames are subdued, but you are seeing secondary burning) . . . if your wood is very well seasoned you can then cut the air back to nothing (well technically these stoves are always getting air, but you know what I mean) . . . and at this point you just need to watch the temps for a bit and enjoy the light show for several hours . . . when the wood reaches the late coaling stage I reload the start the process over again.

I have a new Oslo, and have been trying to figure it out for the last couple of weeks! This morning, I finally got the stove top up to 600; and the kettle, for the first time, actually boiled! I used progressively larger splits on the fire - but didn't put anything on over about 3 inches! This seems to be the answer for me. At 600, I gradually dampered the stove down until it was all the way to the left. I easily got a 7 hour burn and actually had lots of red hots to get the fire going again. Stove top temp at refill was about 250. HehHeh . . . 3 inch round and splits are most definitely not large. I use this size wood on a cold start . . . I generally use larger wood for longer burns . . . but that said I think you did well and it sounds as though your wood is well seasoned which is fantastic.

When the weather gets colder, I'd sure like to "run" my Oslo at 550-ie. keep it at 550 for 6 or 7 hours. I simply have no clue how to do this. Not going to happen . . . what you will get is what you had the other day . . . you will have visible flames for 3-4 hours and wicked good heat from the coals for 5-8 hours . . . a lot will depend on how well seasoned the wood is, type of wood, etc. However, you will not have 550 stove top temps for the whole 6-7 hours . . . it will hold there for a while and then slowly begin to drop off . . . the good news is a well insulated house and the heat that continues to radiate from the coals will keep the house warm for a while.

Your input would be appreciated!
 
Since a) Jotul's manual for the Oslo specifically mentions 400-600 degree temps and b) one member asked a Jotul dealer at what temp would there be a problem with overfiring the number they gave was 700 degrees I tend to keep my stove top temp at 450-550 degrees . . . it gives me a little bit of a buffer and keeps me away from the "Oh crap Temp Zone."
 
perplexed said:
I have the 550 insert and it likes to cruise in the upper 500's to the upper 600's. It usually gets into the 700's every few days for awhile and handles it just fine. My comfort range is in the 600's.

Perplexed, where/how to you measure your temps?
 
Great info Jake.
 
450 to 500 normally. Then to 550 when
the outside temp goes to zero.

Great Norse design!
 
Interesting to note in the manual that it appears only the US section goes into temperature detail. The other languages just warn not to get it so hot that the stove glows red.
 
I have had my stove in the high 700's a couple of times by accident with no ill affects. Not trying to make a habit of it though.... Jakes overview seems right on, though i tend a little hotter.
 
I like to keep mine between 450 and 550. I've gone to 600 a few times...then back it down from there. I'm still experimenting, but it's really neat when I can get it loaded right and the air control right and it'll just hang at 550 happily for awhile. Based on the owner's manual, I was under the assumption that 600 was the "max" temp you should run the stove at. I thought anything over that was over firing. So I guess there's about a 100 degree "buffer" zone before it overfires?

Anyone notice the low rumble you get when the fire gets ripping and the secondaries kick in? It's funny, I can almost tell just by the sound, when it's time to start backing the air control down. It's almost like I don't need to look at the thermometer.
 
Skier76 said:
Anyone notice the low rumble you get when the fire gets ripping and the secondaries kick in? It's funny, I can almost tell just by the sound, when it's time to start backing the air control down. It's almost like I don't need to look at the thermometer.

Yeah, it was a bit unsettling the first time I experienced it. I'm still amazed by it. I'll get the stove up to the 400* range, shut the air down and the secondaries just roar. Very impressive to see the small lazy flames on the wood and the gasses furiously igniting above. There's nothing like efficiency!
 
The secondaries put on quite a show. It reminds my wife and I why we went with the Jotul...a nice view of what's going on inside of the firebox.
 
Yes, the sweet spot for the secondary is 450 to 550 F.
A bit more during deep winter.

Much like seeing a small Aurora Borealis inside our stoves.
Other brands do it nicely too.

But we prefer the Norse way!
 
op_man1 said:
perplexed said:
I have the 550 insert and it likes to cruise in the upper 500's to the upper 600's. It usually gets into the 700's every few days for awhile and handles it just fine. My comfort range is in the 600's.

Perplexed, where/how to you measure your temps?

I use an IR therm. pointed onto top center of firebox where blower air exits my insert mid-way between opening and the flue - probably 4" in from the opening.
 
cycloxer said:
Gotcha. Yeah Jotul just recommends 400-600 for the optimal burn. Then they say not to overfire your stove and make it glow. They don't specify a # there.

The color of hot iron or steel is how an experienced blacksmith judges the temperature of his work. A so called "black body" will begin to glow a faint, dull red at about 900ºF. That is true for just about any material - it's a quantum physics thing (and, hey, I don't argue with those guys). My wife's torch-fired glass beads begin to glow at that temp in her kiln, and so would a stove (regardless of the color... a "black body" doesn't actually have to be colored black).

A full stove can easily runaway from 600ºF to 900º very quickly. It won't continue to rise above a certain point unless you can feed it more air. Chimneys with very strong draws can help this to occur, but a well designed stove is somewhat limited in air consumption by the size of the max draft opening. A forge, OTOH, has air forced through the tuyére by a bellows or an electric fan. With an increase in air like this, temps in the 2500ºF+ range are possible.

If your stove ever hits 2000ºF, it will glow bright yellow-white. But if you see it glow at all, it is about 900ºF at the point you can first detect it in a darkened room. If it looks bright red, it is surely well over 1000ºF.

My old Scandia (a clone of the Jotul 118) never got red no matter how hot I tried to get it. I never had a thermometer on that one, but I'll guess I had it well over 800ºF on numerous occasions. It just didn't have a large enough draft opening to get glowing with the existing chimney.

For the record, although it's not a Jotul, my VC Vigilant seems to want to climb up to about 800ºF in updraft mode and stay there, even with a full load. Shutting the damper down, both flue temp and stove top temp drop quickly, but the stove temp will rise again during the burn and then seems to want to stabilize at about 650ºF for a few hours before very slowly dropping over several more hours. I'm starting to just trust the design and let it run that hot. Stove has a nice clean look inside after several weeks of burning not-so-dry cherry. No warping, and no sign of creosote anywhere.
 
op_man1 said:
perplexed said:
I have the 550 insert and it likes to cruise in the upper 500's to the upper 600's. It usually gets into the 700's every few days for awhile and handles it just fine. My comfort range is in the 600's.

Perplexed, where/how to you measure your temps?

opman, there a few threads on where to put the thermometer on a Jotul insert. The best place is right inside where the air blows out. Put the 500 degrees setting pointing out, that is the most normal place you will see it + or - a 100 degrees. It is nice also because you will still not see the thermometer unless you try, and it is accurate because it is right on the top of the stove.
 
I've had my Castine run away a couple of times when it had a hot bed of coals and I crammed the firebox full of wood. Temp spiked to 800 a couple of times, which I know is not good. The majority of the stove was fine, but the front air deflector was glowing a bit. I inspected after the first time this happened and everything looked okay. The dealer told me he gets warped top plates from over-firing, probably from people who let the stove get away and didn't pay attention. I know once you get the Castine to 600 it doesn't take much to hit 700+ if you don't back off the air significantly.
 
when you guys state tems, you mean the stove top temp?
since i have a zero clearance insert, will using a ir thermometer on my stoves inner side walls provide an accurate measurment of what temps i should shoot for?
i assume 700 on a sidewall in my stove box is not as hot as a 700 degree stove top?
 
Battenkiller said:
cycloxer said:
Gotcha. Yeah Jotul just recommends 400-600 for the optimal burn. Then they say not to overfire your stove and make it glow. They don't specify a # there.

The color of hot iron or steel is how an experienced blacksmith judges the temperature of his work. A so called "black body" will begin to glow a faint, dull red at about 900ºF. That is true for just about any material - it's a quantum physics thing (and, hey, I don't argue with those guys). My wife's torch-fired glass beads begin to glow at that temp in her kiln, and so would a stove (regardless of the color... a "black body" doesn't actually have to be colored black).

A full stove can easily runaway from 600ºF to 900º very quickly. It won't continue to rise above a certain point unless you can feed it more air. Chimneys with very strong draws can help this to occur, but a well designed stove is somewhat limited in air consumption by the size of the max draft opening. A forge, OTOH, has air forced through the tuyére by a bellows or an electric fan. With an increase in air like this, temps in the 2500ºF+ range are possible.

If your stove ever hits 2000ºF, it will glow bright yellow-white. But if you see it glow at all, it is about 900ºF at the point you can first detect it in a darkened room. If it looks bright red, it is surely well over 1000ºF.

My old Scandia (a clone of the Jotul 118) never got red no matter how hot I tried to get it. I never had a thermometer on that one, but I'll guess I had it well over 800ºF on numerous occasions. It just didn't have a large enough draft opening to get glowing with the existing chimney.

For the record, although it's not a Jotul, my VC Vigilant seems to want to climb up to about 800ºF in updraft mode and stay there, even with a full load. Shutting the damper down, both flue temp and stove top temp drop quickly, but the stove temp will rise again during the burn and then seems to want to stabilize at about 650ºF for a few hours before very slowly dropping over several more hours. I'm starting to just trust the design and let it run that hot. Stove has a nice clean look inside after several weeks of burning not-so-dry cherry. No warping, and no sign of creosote anywhere.

Thanks for this temp. info. I have never gone above 825* (accidental) with our 550 BUT

this morning I was not in the stove room with first load of the day. Had it at 1/4 closed down only. Usually story - got side tracked - realized stove was on it's own. Checked temp. and it was 915* center top 625* on the top sides away from flue. Your info. on the temps. at which metal glows I knew I was okay as nothing was glowing - I can see the flue collar through the blower vents. I knew I had several more degrees to go.....SO BIG THANKS FOR THE NUMBERS!!!!

Thanks to all info. here I knew exactly what to do without panicking. Simply shut air down. Turned on blowers and opened back door to let cold air in and placed a small fan in front of the blowers to cool it back down.....Came back into mid 800* so I was able to relax a bit knowing it was on it's way down and not climbing.

All of the above I learned here reading through threads over the years. Without the knowledge I have gained here I really would have panicked and probably would have thrown water on the fire. :shut:

I am glad I entered the room when I did. Glad it was me and not one of the Kids or husband - they don't listen when I tell them ANYTHING and they would have panicked. And glad for all who share their experiences here. You do make a difference. ;-)
 
Hehe, it gets exciting the first time you have a raging inferno inside the box and you see the big # on the thermo. You kind of do the ruh ruh, whadda i do now?
 
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