Learning the Jotul Oslo

[rgram]

I get the stove top temp up to about 500-550 when its cold out, then start backing it down and it will cruise in the mid 400s range for a few hours.

Firefighterjake I've been impressed myself and I'm not just a weekend burner.
I'll have the stove going 24/7 for several weeks on end all these years.

 

[Toploader]

For me it definitely depends on how much heat I need, but if it's just cold, say 32 F, I'll start reducing the air when the stove top is around 350 and try to make it hold at 400. On a full load this is very doable, however, if loaded on a good bed coals with temps already close to 300 the temps will likely rise up to 450-500 once the secondaries kick in. If it's very cold I'll let the stove run a little harder 550-650 is the high range. Generally the temps always seem to rise for me once I close the air off completely, if they drop you know you've shut it down too much or too soon.

 

[Sniper8541]

I haven't quite correlated the look of the fire with stove top temps yet. I've been paying more attention to the look of the fire than what the thermos say. Once I feel proficient at being able to control the look of the fire, ill start dialing in temps. So far it's been getting to 450-500 before I turn it down, but I'm having trouble keeping the flu under 200. Too much air I'm guessing, or maybe an in line damper is needed to control that better? The house was at 79 last night, and that was with the air closed and just a couple splits every couple hours and temps around 300. Haven't figured out what temp to run it at to not over heat the house. Big difference between this and the VC! Thanks to everyone who has offered help.

 

[firefighterjake]

I haven't quite correlated the look of the fire with stove top temps yet. I've been paying more attention to the look of the fire than what the thermos say. Once I feel proficient at being able to control the look of the fire, ill start dialing in temps. So far it's been getting to 450-500 before I turn it down, but I'm having trouble keeping the flu under 200. Too much air I'm guessing, or maybe an in line damper is needed to control that better? The house was at 79 last night, and that was with the air closed and just a couple splits every couple hours and temps around 300. Haven't figured out what temp to run it at to not over heat the house. Big difference between this and the VC! Thanks to everyone who has offered help.

Ummm . . . Part of your problem with such high temps might be adding just a couple of splits every two hours . . . plus it was rather on the mild side here . . . assuming it may have been the same with you as well.

This stove, like most modern secondary burner stoves, really runs better in cycles. Load it up, burn down to small coals, load it up, burn down to small coals, repeat. With practice you can avoid a big temperature difference in the house while at the same time keeping the temp at warm temps and not having to reload so often. Reloading so often will result in high temps, a lot of wood used up and in the end a whole bunch of coals building up in the firebox.

Part of the problem by going by the way the fire looks (at least at first) is you can have a fire that looks very intense and it may not be putting out much heat . . . I'm pretty good at gauging the fire now by the way it looks and sounds, but I still trust my thermometers more than I do what own senses.

 

[Sniper8541]

Ummm . . . Part of your problem with such high temps might be adding just a couple of splits every two hours . . . plus it was rather on the mild side here . . . assuming it may have been the same with you as well.

This stove, like most modern secondary burner stoves, really runs better in cycles. Load it up, burn down to small coals, load it up, burn down to small coals, repeat. With practice you can avoid a big temperature difference in the house while at the same time keeping the temp at warm temps and not having to reload so often. Reloading so often will result in high temps, a lot of wood used up and in the end a whole bunch of coals building up in the firebox.

Part of the problem by going by the way the fire looks (at least at first) is you can have a fire that looks very intense and it may not be putting out much heat . . . I'm pretty good at gauging the fire now by the way it looks and sounds, but I still trust my thermometers more than I do what own senses.

Good tip! With the VC I always wanted a nice bed of coals so I would load more frequently to keep the bed going for the overnight burn. Ill let it burn down then reload, thanks.

Also, when the secondaries are going is it good to only have flame at the tubes? And if so, what if they go out then reappear a second or two later? Kinda nervousness of the gasses flashing when they build up then reignite.

It's been really warm here too so far this season. Not complaining considering its saving wood for next year (fingers crossed)!

 

[firefighterjake]

Good tip! With the VC I always wanted a nice bed of coals so I would load more frequently to keep the bed going for the overnight burn. Ill let it burn down then reload, thanks.

Also, when the secondaries are going is it good to only have flame at the tubes? And if so, what if they go out then reappear a second or two later? Kinda nervousness of the gasses flashing when they build up then reignite.

It's been really warm here too so far this season. Not complaining considering its saving wood for next year (fingers crossed)!

Mixed feelings on the weather . . . seemed like a relatively mild Fall . . . but I snowmobile so I wouldn't mind seeing some cooler weather and snow.

Yes . . . reload when the coals are fairly low . . . I tend to reload with small splits once I have the coals down to the size of plums . . . sometimes smaller even. A lot depends on the heating needs -- when it's mild out you and the house is still warm you may be able to reload on coals that are even smaller, but when it's cold out you may need to reload when the coals are quite large to keep the heat output.

Some folks get caught up equating the flame of a fire with heat . . . when truthfully you get as much heat from those hot coals. The way I look at it . . . the fire heats up the stove and the stove stores up a lot of that heat and radiates it out for a very long time, well after those flames are no longer burning.

Secondaries can manifest themselves in many ways . . . some folks have reported seeing what look like propane BBQ jets coming out of the secondary burner tubes . . . I typically get the Portal to Hell has opened up in the upper part of the firebox (at least with the billowing flames it looks like I've managed to open up a Portal to Hell. What I like to see best is a more gentle rolling fire in the top third of the firebox or what you've described . . . I call them the Secondary Fireworks . . . you see nothing for a second or two and then a blast of fire in the upper part of the firebox as the collected combustible gases ignite and then there is a pause and then they burst into flames again.

There is no real reason to worry unless a) you've got something smoldering in the firebox and it is building up a huge charge of combustible gas -- I've seen this when I tossed in some cardboard on to hot coals and then left the air control shut all the way and the door shut or b) you've shut down the air so much that it suffocates the fire completely or lowers the flue temp to the "making creosote temp." Typically you can open the air up just a dite and this should give the stove enough oxygen to get a sustained secondary burn.

 

[Sniper8541]

I guess I was a bit misleading with watching the fire not temps. I don't shut it down if the fire looks like it's burning really hot, ill check the thermo of course. If its not past 500 ill let it go until I feel like it's ready to start shutting down. If I let it stay open to 500, the flu temps get up past 200 though. Don't like that. I guess what I meant was I don't know what stove temps I need to heat the house yet, so for now I'm paying more attention to how the fire behaves.

The first thing I thought when I saw the secondaries was it looks like the northern lights. Pretty cool.

Thanks for the help.

 

[Sniper8541]

What's that blue/green flame about?

 

[firefighterjake]

I guess I was a bit misleading with watching the fire not temps. I don't shut it down if the fire looks like it's burning really hot, ill check the thermo of course. If its not past 500 ill let it go until I feel like it's ready to start shutting down. If I let it stay open to 500, the flu temps get up past 200 though. Don't like that. I guess what I meant was I don't know what stove temps I need to heat the house yet, so for now I'm paying more attention to how the fire behaves.

The first thing I thought when I saw the secondaries was it looks like the northern lights. Pretty cool.

Thanks for the help.

That's how I described them as well! . .. Northern Lights . .. as they would flicker in and out of existence.

 

[firefighterjake]

What's that blue/green flame about?

Could be a bit of mineral that the tree took up . . . or the flame there is a little hotter than normal . . . personally I would guess it was a bit of mineral taken up by the tree.