How do you get your Oslo stovetop to 600 degrees?

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logger said:
pen said:
logger said:
When its colder out, I like to keep the air open full on a load or two until I hit 600, then when I shut her down it stays hotter longer. If your draft and wood are good, you should be able to hit 600 no problem with the air open. Id try resplitting your wood to skinny splits and keep feeding the box with the air open or 3/4 open until you reach 600. Then you can load bigger splits, let them char, then shut her down in increments and cruise in the 500s and 400s for a while. If you cant do that, than something is hindering your burns (wood or setup?).

Sorry, but something is wrong here. What you just described is a system that is not operating correctly.

It could be from less than optimal draft, or it could be from wood that is too damp, but regardless, leaving the air wide open for 2 loads to get the unit to stay hotter is not right. If it is staying hotter longer I would assume it is because the stove is 1/2 full w/ coals by the time you get the 3rd load in there.

That stove should be hitting 600 w/ the air at 50% or less no problem.

Running with the stove's air wide open will really speed up the rate that air moves through the stove and up the chimney, taking a lot of heat up and out with it.

If it is necessary to keep the air open this far to get temps around 600, there is a problem

pen
I disagree 100%. Im talking my first fire of the day here, Pen. Im on my 3rd yr w the Oslo and have absolutely no problem heating the entire house all winter w nothing but the stove. I use small splits to get a new fire going. They burn pretty quick so I dont always get to 600 on this initail load of kindling, but If I want the house warm quickly, I leave the air open to get coals quicker so I can get that next load in and start to shut her down sooner and get my heat. Im aware of hot air going up the chimney with the air open, but with kindling my goal is to establish some coals to get the big stuff in and start shutting her down for secondaries.

Maybe you misunderstood but my 1st load is kindling, in which case I leave the air open. Then my second load is reg splits and once it chars, I shut her down.

For my 1st fire in a cold stove, I will hit 600 much faster with the air open than partially closed. Loading on coals is a whole diff ball game.

If it works for you, it works for you is my motto Logger . . . but I'm curious why your first load is only kindling. On my first load with coals I typically only use 2-3 pieces of kindling and then load the whole kit and kaboodle up with splits and rounds . . . and on a cold start I may use 3-5 pieces of kindling, but go with the top down method of fire starting so I don't have to do a reload for several hours. I do keep the side door ajar until the temp in the flue is plenty hot though . . . and then start shutting things down which generally brings the temp up in the stove.

But again . . . if it works for you, it works for you . . .
 
firefighterjake said:
logger said:
pen said:
logger said:
When its colder out, I like to keep the air open full on a load or two until I hit 600, then when I shut her down it stays hotter longer. If your draft and wood are good, you should be able to hit 600 no problem with the air open. Id try resplitting your wood to skinny splits and keep feeding the box with the air open or 3/4 open until you reach 600. Then you can load bigger splits, let them char, then shut her down in increments and cruise in the 500s and 400s for a while. If you cant do that, than something is hindering your burns (wood or setup?).

Sorry, but something is wrong here. What you just described is a system that is not operating correctly.

It could be from less than optimal draft, or it could be from wood that is too damp, but regardless, leaving the air wide open for 2 loads to get the unit to stay hotter is not right. If it is staying hotter longer I would assume it is because the stove is 1/2 full w/ coals by the time you get the 3rd load in there.

That stove should be hitting 600 w/ the air at 50% or less no problem.

Running with the stove's air wide open will really speed up the rate that air moves through the stove and up the chimney, taking a lot of heat up and out with it.

If it is necessary to keep the air open this far to get temps around 600, there is a problem

pen
I disagree 100%. Im talking my first fire of the day here, Pen. Im on my 3rd yr w the Oslo and have absolutely no problem heating the entire house all winter w nothing but the stove. I use small splits to get a new fire going. They burn pretty quick so I dont always get to 600 on this initail load of kindling, but If I want the house warm quickly, I leave the air open to get coals quicker so I can get that next load in and start to shut her down sooner and get my heat. Im aware of hot air going up the chimney with the air open, but with kindling my goal is to establish some coals to get the big stuff in and start shutting her down for secondaries.

Maybe you misunderstood but my 1st load is kindling, in which case I leave the air open. Then my second load is reg splits and once it chars, I shut her down.

For my 1st fire in a cold stove, I will hit 600 much faster with the air open than partially closed. Loading on coals is a whole diff ball game.

If it works for you, it works for you is my motto Logger . . . but I'm curious why your first load is only kindling. On my first load with coals I typically only use 2-3 pieces of kindling and then load the whole kit and kaboodle up with splits and rounds . . . and on a cold start I may use 3-5 pieces of kindling, but go with the top down method of fire starting so I don't have to do a reload for several hours. I do keep the side door ajar until the temp in the flue is plenty hot though . . . and then start shutting things down which generally brings the temp up in the stove.

But again . . . if it works for you, it works for you . . .

Hi FFJ,
Maybe I wasnt clear. I was speaking of when its cold out and Im starting my first fire of the day in a cold stove with no coals. My first load is only kindling because it gets my stove hotter faster than reg splits of my oak and locust. So does leaving the air open on this initial load to get the stove up to temp faster. Then I load reg splits w air open only at first and gradually shut down. On hot coals its different. I open air, load her up, shut her down. I've read many of your posts on the Oslo and run her pretty much exactly as you do. I just prefer to use small splits in the begining to get the temp up and for that I leave air open or 3/4 open til Im up to temp.

Also, I was helping a poster who has trouble reaching 600. Since thats the case, I figured the best way for them to try reaching that would be to use smaller splits with the air on the open side. I too have used kindling w splits in together, but I get high temps faster with all little guys in the first load. To each his own.
 
logger said:
Maybe you misunderstood but my 1st load is kindling, in which case I leave the air open. Then my second load is reg splits and once it chars, I shut her down.

Got it, that makes much more sense. I didn't realize it was a kindling fire. Was envisioning the first load of the day in cold weather being a stove full of wood on hot coals! If you do that w/ the air wide open in a good system things could get pretty interesting :gulp:
 
pen said:
logger said:
Maybe you misunderstood but my 1st load is kindling, in which case I leave the air open. Then my second load is reg splits and once it chars, I shut her down.

Got it, that makes much more sense. I didn't realize it was a kindling fire. Was envisioning the first load of the day in cold weather being a stove full of wood on hot coals! If you do that w/ the air wide open in a good system things could get pretty interesting :gulp:

Yah, the misses did that once but I walked in from work thankfully and caught it a little over 700. Probably couldla got a lot hotter. She was in the kitchen cooking my dinner so I didnt yell for too long. lol
 
logger said:
pen said:
logger said:
Maybe you misunderstood but my 1st load is kindling, in which case I leave the air open. Then my second load is reg splits and once it chars, I shut her down.

Got it, that makes much more sense. I didn't realize it was a kindling fire. Was envisioning the first load of the day in cold weather being a stove full of wood on hot coals! If you do that w/ the air wide open in a good system things could get pretty interesting :gulp:

Yah, the misses did that once but I walked in from work thankfully and caught it a little over 700. Probably couldla got a lot hotter. She was in the kitchen cooking my dinner so I didnt yell for too long. lol

Been there before air was left wide open the stove was 700 the probe read 1300.
 
I guess I don't know why you would want an Oslo run up to 600. To me that just means you're blowing btu's up the chimney instead of heating your home. The way I run my stove I'm very happy when it gets up to around 550 and cruises around 500 for a couple hours. I get a little nervous if it gets to the upper 500's....... :)

Then again, the brakes on my car always last longer than the brakes on our son's cars....... :)
 
I like the car brakes analogy. In some respects, I am in a race... although it's a race against the clock and not against cars.

I'd like to be able to get the Oslo to 600 because of the way we use it in our home. We use it as a space heater for our basement, and we love it. On a typical Saturday morning, our basement is around 50 degrees. I get up early and build a fire in a stone-cold stove in a stone-cold room. I have my coffee wearing a coat and watching the kindling burn. The race is on, because I know the family will want to come down to the basement once they're awake.

The stove temperature makes a big difference in how much heat our Oslo gives off. At a stove top temperature (STT) of 400, the room temperature rises about 1 or 2 degrees per hour. At 500 degrees STT, the room temperature rises about 5 degrees per hour.

So, every bit of higher STT helps me warm up our basement faster, which means the family enjoys it more. That's the goal, nothing more. I don't mind sending some extra heat up the flue. With a tall flue, hotter exhaust also means less chance for creosote build up.
 
I dont mean to sound as if 600 degrees is some sort of goal i seek for. Could it be done with my set up, yes it could. I like to know how to fully control the device, any thing for that matter. That means targeting a temp and through good wood, patience and practice i can.
On average i typically was looking for longest burn with heat output, and will remain the same when shes up on her new hearth. 500s is where i see the longest burn thats cranking usable heat for hours. For me.
Pm01, those temps saturday morning...i would try to have a nice fire friday night. You wont be waking up to stone cold anything down there. Stove should still be in the upper 100s at least with a good fire 8hours later. If anything it should be higher. Then theres no race needed, because youve gotten a head start. I had a small stove that was started cold everyday. I went bigger and better to strech out the burns. I dont come home to cold anymore. But i remember and understand your point.

Shari, brakes last longer with age...and i dont mean the pads or shoes...just ask me, good comparison.
 
Shari said:
I guess I don't know why you would want an Oslo run up to 600. To me that just means you're blowing btu's up the chimney instead of heating your home. The way I run my stove I'm very happy when it gets up to around 550 and cruises around 500 for a couple hours. I get a little nervous if it gets to the upper 500's....... :)

Then again, the brakes on my car always last longer than the brakes on our son's cars....... :)

Dont get me wrong, Im usually burning in the 500s and 400s, but why the heck not run it to 600 on a cold day when you come home from work to a dead stove and a chilly house (manual says 400-600 is optimum)? If you fully read all the above posts, you would've read that the initial problem was the poster could not not get their stove up to 600 no matter what they tried... this is a red flag that something is up, wood or setup maybe. You say you like to get your stove up to 550 and then cruise. Is there that much difference between that and 600 that you really have to post a silly analogy? And you've never put the air down after a load and have the stove at 600 in midwinter? How in the world is that blowing btus if your heat is off and the house is warm? Everyones got different heating situations.
 
Mine will go up to 700+ on a packed load of dry oak, seasoned 3 years, smaller size splits.

It'll go up to 600+ on almost any load, packed, smaller size splits.

I can shut the air completely off if I run it up to 650 on a packed load.

I normally run it up to 550 to 600 before turning the air back.
 
logger said:
silly analogy?

Really?

We heat 24/7 with wood.

I haven't turned our furnace on in over a year.

I live in Wisconsin.

It gets cold here.

I'm warm.

:)
 
Nothing wrong running up to 600, says so in the manual. But 24/7 heating, sole sourced from a stove, not needed most of the time. Insulation in the home helps.

No furnace here either. Have to figure out what works best for you of course. Certain situations apply.
 
Shari said:
logger said:
silly analogy?

Really?

We heat 24/7 with wood.

I haven't turned our furnace on in over a year.

It gets cold here.

I'm warm.

:)

Impressive... you and most people on this forum. I just dont think the car brakes comment was needed.
 
Best of luck getting those temps up, pmo1. Unfortunately, I think many here did not read your original post on how you cant get the stove up to 600.
 
Excellent point on the post before this one, many of us got off on a tanget including me and didn't really help. You should be able to get to 600F pretty easily. I know I can with my Lopi insert. I think the most variability in this business is in the wood and the dryness thereof, the type adds variety too but dryness or lack of dryness is the king of determining heat output. Try a load of Eco Bricks as there is no doubt on how dry these things are. 6 to 8 packed close together ought to be able to get your stove top up to 600F, just be careful they don't run away from you when/if you approach 600F+. I know the only time I got a little scared is when I packed in about 12 of them on a bed of coals and let them get rolling before shutting down all the way which didn't help much as the secondaries where going wild for an hour or so sending my stove top temperatures to around 750-800F, opening up the door didn't help either. I stayed up a few extra hours that night.
 
I have a whole 5 month's experience burning an Oslo. I have hit 600 degrees once or twice. I burn mostly at 450-500 degrees. I have yet to experience a "runaway stove" in this temp range. Stove temp always comes down as I close off the primary air. The couple times I pushed it to 600, I was able to do it by just keep feeding the fire with 2-4" spilts after the initial start of the fire (air wide open and keeping the side door open longer than normal with reloads). This took 45-75 minutes to get there. As some previous posts have stated, seemed like I was burning way more wood than needed. I need to experiment more with the air at 50% open. I get into the routine of 100%, then 40%, then 10-30% open for my burn cycles.

To hit 600 ==> smaller wood loosely placed in the stove, hot bed of coals and air wide open.
 
logger said:
Hi FFJ,
Maybe I wasnt clear. I was speaking of when its cold out and Im starting my first fire of the day in a cold stove with no coals. My first load is only kindling because it gets my stove hotter faster than reg splits of my oak and locust. So does leaving the air open on this initial load to get the stove up to temp faster. Then I load reg splits w air open only at first and gradually shut down. On hot coals its different. I open air, load her up, shut her down. I've read many of your posts on the Oslo and run her pretty much exactly as you do. I just prefer to use small splits in the begining to get the temp up and for that I leave air open or 3/4 open til Im up to temp.

Also, I was helping a poster who has trouble reaching 600. Since thats the case, I figured the best way for them to try reaching that would be to use smaller splits with the air on the open side. I too have used kindling w splits in together, but I get high temps faster with all little guys in the first load. To each his own.

This explains things a little more . . . however I must admit that even on cold starts I tend to use more kindling . . . but there is still some medium to large splits in the firebox . . . although as the kindling burns down in that first cold start fire I often add another split or two well before the coaling stage . . . pretty much the only time I am comfortable doing so . . . to both bring the temp up and fill up the firebox with the good stuff.
 
pm01 said:
I like the car brakes analogy. In some respects, I am in a race... although it's a race against the clock and not against cars.

I'd like to be able to get the Oslo to 600 because of the way we use it in our home. We use it as a space heater for our basement, and we love it. On a typical Saturday morning, our basement is around 50 degrees. I get up early and build a fire in a stone-cold stove in a stone-cold room. I have my coffee wearing a coat and watching the kindling burn. The race is on, because I know the family will want to come down to the basement once they're awake.

The stove temperature makes a big difference in how much heat our Oslo gives off. At a stove top temperature (STT) of 400, the room temperature rises about 1 or 2 degrees per hour. At 500 degrees STT, the room temperature rises about 5 degrees per hour.

So, every bit of higher STT helps me warm up our basement faster, which means the family enjoys it more. That's the goal, nothing more. I don't mind sending some extra heat up the flue. With a tall flue, hotter exhaust also means less chance for creosote build up.

When we first started heating part time, weekends we would arrive to our cabin Friday night with the temp 45. We sat bundeled up, stuffing the stove with as much wood as it could hold. Your temp rise per hour is about what mine was. Stove temps of 600 to 750 was not uncommon. I think the fastest way I found to get a cold stove up to 600, was a lot of wood surface area with room to burn. As it burnt and there was any room I'd add more wood. once i got above 400, 600 was no problem. That said I don't do this much anymore, we have the heat come on about noon time. 6 hours later the house is 65.
 
Glad Im not the only one who likes to get the beast hot, especially on that first fire when the house is cold. Id think we'd all agree that when the house is already toasty, theres really no reason to spike to those temps, but everyone should be able to if they need to. That is where pm's (the original poster) problem lies.. not being able to get those temps no matter what method was tried. Lots of good advice here to try, pm. Let us know how it goes.
 
I agree -- lots of great information, and I'm grateful for the input. I look forward to trying some of the suggestions.

If I can get my operating technique improved, then I can start experimenting with draft adjustment as well. With a 40-foot 6-inch insulated flue, I think I probably I have draft to spare when the stove is hot. If I shut down the air control when the stove is really running, I can get secondaries shooting all the way to the glass, down the glass, and back to the wood below.

By restricting the intake port, I can go all the way from raging secondaries down to snuffing the fire almost completely out, depending on how much I cover the port. I think I need some draft restriction when things are hot -- but I just don't know how much. I keep wondering if I've got too much draft or too little, depending on the restriction amount.

Now I can work on my operating technique, and then start experimenting with different draft adjustments to see how things go.
 
40 ft, without knowing the rest of the setup, id say your a canidate for a pipe or key dampner.

Id think it would be better to cut the draft, over the intake air as a way to control the burn.

Good luck.
 
I honestly don't know whether a pipe damper or an intake restriction would give better results. The intake restriction is easier for me to test, and it requires no drilling or disassembly of the stove pipe. It also means I never have worry about smoke backing up into the room -- there's always an open flue trying to suck it up, even with the stove door wide open.

I've always thought that draft was just a function of the pressure difference the stove sees between intake and exhaust, and that the fire didn't really care where the restriction was. There's also a comment in the "Florida bungalow syndrome" writings that intake restrictions might work well, and the logic presented seemed to make sense to me.

I'm always trying to learn, though, so if others have seen that a pipe damper works better, I'd love to hear about it.
 
Interesting thread. So many variables to consider. Split size, placement, draft, pipe damper, wood moisture, timing on shutting the air down, increments, etc.
If you are into it, like me, figuring out the stove and getting optimal performance will be fun. If your not into it, like my wife, it's more like a frustrating pain in the ass. :zip:
 
I read through the prior messages quickly, so maybe this was mentioned already - but I didn't see it. I start a fire with 1/4 of a fire starter stick, some kindling and small logs. After the fire has started, I have the air control shut down until I have mostly blue flames. Orange/yellow flames are needed during start-up, but I go for blue flames and efficient burning after that.

The Oslo is/was already the cleanest burning Jotul, but I think setting the air control for blue flames gives the highest temps using the least amount of wood, with the cleanest burn. The glass stays cleaner with this setting, too.

If the wood is not dry enough, or if the air intake is too high, I get yellow flames and lower stove top temps. A walk outside means I easily smell the smoke, so the primary and secondary burns are not converting enough of the wood to heat.

If you're burning "wide open" to try to hit 600 degrees after your fire is already fully engaged, what's the flame color? Yellow flames (IMHO) means a less efficient burn and that some heat/smoke is going up the chimney and energy is being wasted. (My energy too - I have to cut, stack, tote that firewood!) Dial the air intake back, get more blue flames, and then check your temps.

Positioning the logs and setting the air flow for mostly blue flames is like adjusting the gas barbecue's air controls. Blue flame with a bit of orange means the flame is hottest and most efficient.

A great feature of the Oslo is the side door for feeding/adjusting the fire. Shift the wood around a bit so it is cross-stacked and there is good airflow - that also gives a hotter cleaner fire.

Rich
 
Mine routinely slides up to 600. Most often on lading a hot stove beginning to back down and being distracted with air intake at 1/2. With my particular set up it will get hot quickly. I don't really worry if the stove doesn't get past 700-50. Like others said though, it's not the most efficient use of fuel, we heat 24/7.
 
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