Jotul F500 Oslo Burn Time Issues

NewEnglander said:

I really disagree that I'm asking too much of the stove.
All the wood is gone from fully packed to hardly anything within 3-4 hours, 4 is pushing it, the temps are 400-600 for about 3 hours!
If that's asking too much ......

As for the dollar bill there is pretty much no resistance on the side door, but I can't pull it through the front or ash door

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Again, is this your first wood stove? 4 hours is all you're going to get of 400 degree stovetop.

As said, how hard do you need to run it? How I need to run overnight at 0 is a big difference from 30F Although I can heat the whole house at 0 the stove needs to be cycled back up when it hits 300. But even at 0 I don't need to get it any hotter than 500. At 0 I refill ever 3-4 hours at night. Yours and mine has a lot of draft, which burns wood faster. I need to get my air control all the way off when it gets hot, and it still burns. Not out of control, just can't choke it off.

Watch the air control sticking issue. When it gets near the fully closed position it can stick and cause the slide to jump up, opening the air flow.

But safe to say you have real good draft. If you can't get secondary burn happening , sounds like you may also have a air leak. Check gaskets and air control. But it may be all draft a good burning wood.

All stoves cycle up and down. If you can't keep the place comfortably with the cycle the stove may be to small for you situation.

I think the stove is running as intended, but you are either trying to heat too big of a space, or are expecting the stove to do more than it can in low temperatures. 3-4 hours of solid heat (400-600 stovetop), and then coaling stage for at least another 4 hours (200-350 stovetop). What stove is the Oslo replacing? If your draft was a problem I would think you would have overfire issues, like 700+ stovetop temps when shutting the air down. When the air is completely shut down you shouldn't see any flames coming from the bottom of the firebox, do you?

NewEnglander said:

I agree, it's not over firing, it never goes beyond 600.

I think like I said the side door is leaking air in, the dollar bill pulls through with zero resistance! It's brand new stove! We tried a brand new door replacement, it was worse!

I'm not getting 400-600F temps for 4-6 hours, far from it!

I'd say 500F temps for two hours, and by hour 3-4 it's under 400F

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I said 400+ for 3 to 4 hours, max. If the side door was leaking you should see flames coming off the wood on that side of the firebox when the air is shut down. What stove did you have prior to the Oslo, and how big is the home?

NewEnglander said:

I agree, it's not over firing, it never goes beyond 600.

I think like I said the side door is leaking air in, the dollar bill pulls through with zero resistance! It's brand new stove! We tried a brand new door replacement, it was worse!

I'm not getting 400-600F temps for 4-6 hours, far from it!

I'd say 500F temps for two hours, and by hour 3-4 it's under 400F

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Yep all sounds about normal. What square footage and condition of the space are you trying to heat?

If you have gasket leak and a good draft that's not helping. Replace the gasket.

NewEnglander said:

I've replaced the gasket it didn't change, I even tried a larger gasket, a new door also, still not tight

The room is 24x20, oil heats the remainder of the home, the home is well insulated

Previous stoves, Vermont Castings, Stanley's, Olymberyl, among a few

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You can't heat that sized space effectively with the stove, or you are looking for a longer burn time? You should easily heat that space, plus some.

I'm heating 28' x 36', two floors. The stove room is 28' x 16' with cathedral ceilings. Well insulated with good windows. I really have to watch what were doing with the stove as we have a lot of candles that could easily be melted.

Oak cannot be seasoned in a year. Cut and stacked it is sorta burnable in two years, but three is really required for full seasoning.

You are not going to get 400 - 600 deg. temps for four hours. That would be pretty much max output for that period, and the amount of wood you can put in the stove does not have enough btus to achieve that. A four to five hour cycle is about right for that size fire box, with temps dropping to 350 deg. for the last couple of hours. I hold mine at 500 for maybe an hour, at most, then around 400 deg. for a couple of hours, then 350 or so for a couple more. This provides enough heat for our house of 2500 sq. ft. here in SW Missouri under all but the most extreme weather conditions.

Over night burns should leave you with a significant bed of coals after eight hours. The last three are going to give stove top temps of 250 to 300 deg.

It is absolutely possible you have an air leak.

By the way, where are you all measuring your stove temp on the stove? I've a Rutland thermometer and I've tried it in different places.

Right now I reloaded the stove, and it's up at 700F, yellow flames, despite the air inlet fully closed[/quote]

That is definitely an air leak. I suspect the ash pan door if you are getting that high a temperature.

Jotul recommends placing the thermometer at any of the four corners on top. Most people use one of the rear corners.

NewEnglander said:

Temps up over 700F now despite the air inlet fully closed now for over half an hour, the temp is still rising

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NewEnglander said:

I agree, it's not over firing, it never goes beyond 600.

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If you're getting over 700 peak then start then cutting the air earlier may help extend your burn time. If you cannot get the temps up then the wood may be a bit wet.

I have not seen anyone mention split size. You may need to split larger in the future but large splits of hardwood will need more than 1 yr to season (heck small splits of oak/locust/hard maple need more than 1 yr).

You have to understand why everyone here will question the wood. If we all had a nickel as they say...

A key damper may be the ans. if your draft is overly strong. In that case the overdraft may be strong enough to pull air even if the gaskets are good and everything is pretty OK.

700+ degrees is very high for an Oslo, or any stove for that matter!
Is the thermometer correct?

NewEnglander said:

Temps up over 700F now despite the air inlet fully closed now for over half an hour, the temp is still rising, and I even put more steel wool in the air inlet in the bottom of the stove

I think that Jotul need to replace this stove, and while we are at it add the butterfly damper

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Your story has changed within 2 hours. I asked if you were getting overfire temps, you said no. Your burn times are being shortened by the high initial temperatures, which is most likely because of the strong draft, or an air leak. Start with a damper in the pipe.

Valhalla said:

700+ degrees is very high for an Oslo, or any stove for that matter!
Is the thermometer correct?

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My Rutland was never accurate. Always off 50-100 degrees but I can't remember if it was high, or low.

Could you put an incense stick near the edges to see if there is a draw?

Have you got your stove under control? Did the temps stop rising? Last you posted was 750 half an hour ago. Hope that was as high as t got...

NewEnglander said:

The story may have changed because this stove has become so unpredictable!
Its now down to 450F, we are only 1 hour and 15 mins into this burn……

I am trying to be exacting as possible

By the way someone asked earlier is the gas coming from the tubes on the top of the firebox or the wood, its coming primarily from the tubes but only from the middle to the right hand side of the stove

Air inlet fully closed, 1 hour 15mins, temp 450 and falling

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If the flames are coming mainly from the tubes I would guess that an air leak is not the issue, but rather the strong draft. You'll need to shut the air down sooner to avoid the overfire temps and prolong burn times. Next time you load the firebox full, snap a picture so we can see how much fuel you're actually getting in there.

Rearscreen said:

Could you put an incense stick near the edges to see if there is a draw?

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This is a good test as well.