Jotul F500 oslo burn times

[PASmoker]

Having issues with getting more then 5 hr burn times out of it, I try and fill it as late at night as possible, around 11pm, usually have a nice bed of coals and the stove top is around 400* . Couple of big pieces of red oak on the bottom and fill the rest with whatever fits till its nice and packed.
Close the damper all the way and go to bed, if I don't wake up by 3-4 am its down to 200* and very little coals to get it going again.
Says 8 hr burn times but it would be totally out if I left it that long.
This is a weekend house and would love to be able to sleep in on the weekends but I'm getting up every 4hrs to keep feeding to keep the house warm.

Any advice to get 1-2 hrs more burn time?

 

[Woody Stover]

Having issues with getting more then 5 hr burn times out of it, I try and fill it as late at night as possible, around 11pm, usually have a nice bed of coals and the stove top is around 400* . Couple of big pieces of red oak on the bottom and fill the rest with whatever fits till its nice and packed.
Close the damper all the way and go to bed, if I don't wake up by 3-4 am its down to 200* and very little coals to get it going again.
Says 8 hr burn times but it would be totally out if I left it that long.
This is a weekend house and would love to be able to sleep in on the weekends but I'm getting up every 4hrs to keep feeding to keep the house warm.
Any advice to get 1-2 hrs more burn time?

I'm assuming that in a vacation home, you don't have a tall stack with strong draft that is pulling a lot of air through the stove and burning up the loads too fast. Have you got good control with the air lever? After establishing a new load, are you able to cut the air back and get lazy flames coming off the wood? What stove top temp does a new load peak at?
If your stove is burning too fast and hot, bigger splits will gas in a slower, more controllable manner. What do your splits measure on a side?

 

[Nigel459]

I try and fill it as late at night as possible, around 11pm, usually have a nice bed of coals and the stove top is around 400*

At 400 that’s pretty hot to reload. Things may be off gassing faster, making things hotter and your draft pull faster hich all contribute to a shorter burn cycle.

 

[PASmoker]

I'm assuming that in a vacation home, you don't have a tall stack with strong draft that is pulling a lot of air through the stove and burning up the loads too fast. Have you got good control with the air lever? After establishing a new load, are you able to cut the air back and get lazy flames coming off the wood? What stove top temp does a new load peak at?
If your stove is burning too fast and hot, bigger splits will gas in a slower, more controllable manner. What do your splits measure on a side?

I have a 20' + stack with good draft , when I load it and turn the level all the way down I have little to no flame for the first hr or so, not sure when it takes off but at some point it burns through everything. I was thinking my splits may not be big enough but I already split everything I had for this year so not much left to test with.
First year with a wood stove so I'm figuring things out as I go, only have a handfull of weekend burns.

 

[Woody Stover]

First year with a wood stove so I'm figuring things out as I go, only have a handfull of weekend burns.

We've all been there. Me and my SIL are trying to figure out the secondary-burn stove I got her; It's our first season as well. She got a burn the other night that she said absolutely filled the box with roiling flame; I got a sweetie-pie of a burn tonight with two big and three small splits. I'm finding that when and how much you cut the air during startup is critical. Let the load get flaming a bit, then start cutting the air in small increments when flue temps get around 200. Cut too much and she stalls, don't cut enough and you get too much wood burning and the secondary goes nuts. Let the fire build again and cut some more, until you get 'er cruising at the final air setting.
I'm going to alter the air intake so it will close further. That way, if we overshoot our mark and get too much wood burning at first, we can cut the legs out from under it..
Trademark on the above procedure, property of begreen.

 

[kennyp2339]

I'm going to alter the air intake so it will close further. That way, if we overshoot our mark and get too much wood burning at first, we can cut the legs out from under it..

If it the primary air your after or control on the secondary air, I'd figure once a certain internal temp hits and secondary combustion takes over, the secondary air gets brought in through a separate air channel and that creates a vacuum which will only get stronger as the fire box gets hotter giving an unlimited air supply

 

[Simonkenton]

I get about 5 hours out of mine.
After 8 hours, still a bed of good hot coals, easy to relight.

 

[xman23]

That's about my night time burn time as well. Can you control the burn rate well, with the primary air? I'd make sure all the door gaskets are good. Check the ash door gasket. It may need the next larger size rope. Most of the time we set the thermostat to 65, and it kicks in by morning.

 

[XmasTreefarmer]

I'll echo Simon's comments - that's what I'd say I get with my Oslo too. Can I go longer - yes. With a tight load of Oak or other dense hardwood and controlling the burn tightly in the beginning, I can go longer and sometimes I am surprised how much longer. The other day I had what *could* be called a 12 hour burn. I had good coals for an easy reload - surprised the heck out of me. I had used good dense oak the night before around 7:00pm and I didn't reload before going to bed. When I went to start the stove around 7:00am, as I stirred things up in there - there were the coals. One of the factors here, and it gets mentioned, but is still often overlooked is ... wait for it ... ASH volume. With that 12 hour burn I had a lot of ash in the stove and was thinking that I'd clean it out in the next few days.

Ash is very insulating and it covers the coals well, restricting the oxygen and air flow over the coals which helps to hold them. I'd suggest giving it a try.

 

[PASmoker]

Another night, loaded it up at 11:30p with just coals at the bottom, no flames when I left it, fully closed, woke up around 4a with a large amount of coals left and the house still at 70* ,< 30* outside , loaded it again , still 70* at 9am. It seems like that's the norm ? And this is heating the whole house with a good size great room with 20' open ceiling

 

[jotul8e2]

I get about 5 hours out of mine.
After 8 hours, still a bed of good hot coals, easy to relight.

Pretty much my experience as well. Usually a decent coal bed up to about eight hours. I am burning white oak with some hickory, which makes a difference.

One "trick" to extend the coal bed life is to place a larger round - five or six inches, say - on the bottom at the back of the final load for the night.

 

[kennyp2339]

A little trick I use to do with my tube stove when I had it, was to do a small reload (small splits) on hot coals, just enough splits to cover the bottom of the box, let that catch with the air on a higher setting, after 20 - 30 min of burning, I would load the bigger splits packing the box and turn the air down letting the flames from the smaller splits catch the bigger stuff, worked pretty well for me, you just need to be mindful of your minimum air setting.

 

[weatherguy]

I'll echo Simon's comments - that's what I'd say I get with my Oslo too. Can I go longer - yes. With a tight load of Oak or other dense hardwood and controlling the burn tightly in the beginning, I can go longer and sometimes I am surprised how much longer. The other day I had what *could* be called a 12 hour burn. I had good coals for an easy reload - surprised the heck out of me. I had used good dense oak the night before around 7:00pm and I didn't reload before going to bed. When I went to start the stove around 7:00am, as I stirred things up in there - there were the coals. One of the factors here, and it gets mentioned, but is still often overlooked is ... wait for it ... ASH volume. With that 12 hour burn I had a lot of ash in the stove and was thinking that I'd clean it out in the next few days.

Ash is very insulating and it covers the coals well, restricting the oxygen and air flow over the coals which helps to hold them. I'd suggest giving it a try.

You maker a good point, with just the right amount of ash you can extend the burn by quite a bit. I used to almost take all the ash out when I did a clean out, now I just take a couple shovel full and spread the rest out.

 

[RyanJ]

We've all been there. Me and my SIL are trying to figure out the secondary-burn stove I got her; It's our first season as well. She got a burn the other night that she said absolutely filled the box with roiling flame; I got a sweetie-pie of a burn tonight with two big and three small splits. I'm finding that when and how much you cut the air during startup is critical. Let the load get flaming a bit, then start cutting the air in small increments when flue temps get around 200. Cut too much and she stalls, don't cut enough and you get too much wood burning and the secondary goes nuts. Let the fire build again and cut some more, until you get 'er cruising at the final air setting.
I'm going to alter the air intake so it will close further. That way, if we overshoot our mark and get too much wood burning at first, we can cut the legs out from under it..
Trademark on the above procedure, property of begreen.

Hi Stover,
I'm getting the same short 5 hr burn times and this stove was supposed to be 12? Did you alter the air intake, if so how did it work out for you and what did you do? I'm considering the same option because I think this thing is getting too much draft. If I can't get this stove to burn where I don't have to do a kindling start every morning I'm going to try to trade it in for a longer burning stove like the Blaze King or Hearthstone. I just feel this thing is going to be a pain in the spring and fall where I want a slow low burn. If you put less wood in it it will just be out in 4 hrs.

 

[Woody Stover]

Hi Stover,
I'm getting the same short 5 hr burn times and this stove was supposed to be 12? Did you alter the air intake, if so how did it work out for you and what did you do? I'm considering the same option because I think this thing is getting too much draft. If I can't get this stove to burn where I don't have to do a kindling start every morning I'm going to try to trade it in for a longer burning stove like the Blaze King or Hearthstone. I just feel this thing is going to be a pain in the spring and fall where I want a slow low burn. If you put less wood in it it will just be out in 4 hrs.

No, I haven't altered the stove. I did install a second flue damper, and that gave a similar reduction in burn rate as the first flue damper I already had in there with her previous stove. It hasn't been very cold for an extended period but when it did, draft got a little stronger.
Even burning loads that are half-full or less, she has had plenty of coals to reload in the morning. She has 15' of stack, but draft is still pretty strong.
If you would, detail your chimney setup. Double-wall connector pipe, straight up, how tall, etc?
What species of wood are you burning? Obviously, soft Maple won't give you the burn time of Oak..