What's wrong with my Jotul F400

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With dry wood you will get a lot more heat and longer burn times. Keep working on getting more wood ready for future years.
 
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That's what I have to work with. I'm sure it would burn better being lower but 23% isn't all that bad..

I bet it's like 25 or better. Damp wood or wood with a higher MC really doesn't burn well with the air turned down all the way

You need to creat a larger supply of wood. The dryer the better, if you want to burn low
 
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Yeah, I went through a couple months with damp maple in the Castine. It was not fun.
 
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My Castine is connected to a 25' masonry chimney and drafts great even with a 90° elbow. I agree that you should spend some time getting to know how the stove operates, before leaving it unattended.
 
With dry wood you will get a lot more heat and longer burn times. Keep working on getting more wood ready for future years.

I need a bigger shed LOL.
 
I need a bigger shed LOL.
I was going to mention that, but didn't want to discourage you. Ours holds 6 cords and for some folks here that's not enough.
 
My Castine is connected to a 25' masonry chimney and drafts great even with a 90° elbow. I agree that you should spend some time getting to know how the stove operates, before leaving it unattended.

You're making it sound like I'm irresponsible. I just installed the stove as my main heating source never thinking it was a different animal than my previous stove. Turning it down low and leaving it 'unattended' isn't the same as leaving a camp fire unattended. After all as a main heating source my stove runs when I'm asleep not to mention when I leave my house.
 
I was going to mention that, but didn't want to discourage you. Ours holds 6 cords and for some folks here that's not enough.

I have been thinking about adding on to it. I did split more wood last year that is stacked on pallets cover with a tarp for now but won't be burned till next season.
 
I have been thinking about adding on to it. I did split more wood last year that is stacked on pallets cover with a tarp for now but won't be burned till next season.

If your going to burn full time I would definitely add to your wood shed or add to your existing shed. I would skip putting the wood on pallets and tarping. Your results will be better in the shed, facing south. Your shed design is good and i would stick with that. I would try to get at least 2 years ahead and then increase form there. Eventually getting to 3 years. I recommend getting to 3 years because some years it gets cold and you'll rip through wood and start to eat into next years wood, then your back to burning damp wood. Your burning experience with your stove will be much better with dryer wood.
 
If your going to burn full time I would definitely add to your wood shed or add to your existing shed. I would skip putting the wood on pallets and tarping. Your results will be better in the shed, facing south. Your shed design is good and i would stick with that. I would try to get at least 2 years ahead and then increase form there. Eventually getting to 3 years. I recommend getting to 3 years because some years it gets cold and you'll rip through wood and start to eat into next years wood, then your back to burning damp wood. Your burning experience with your stove will be much better with dryer wood.

I agree! I built this shed about 3 years ago and wish I had done it 20 years ago. Without question it makes a difference. I can get almost 3 cords in my shed, that is what I average tru a season. I put the wood on the pallets because I ran out of room as I came across more wood that I needed.
 
Aside from the perfect seasoning time for wood, reading the manual for my stove, the recommended chimney height is 15'. Never having a problem with the 2 previous stoves I never even knew what length I had. I did the math and have come up 2' short to only 13'. In examining my chimney I decided to replaced 2 - 3' sections with 2 - DuraVent DuraPlus 36 in. Triple-Wall Stainless Steel Chimney Pipes. I'd like to add another 3' piece but I'm not sure if that will be safe. Does anyone know the length limitations for this chimney pipe?
 
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You can safely add 3 ft and it will make a difference. The chimney pipe will need a proper brace at 5 ft above where it exits the roof.
 
Thanks, I did call DuraVent today and they did suggest the roof bracket. DuraVent did tell me I could install as much as 30' of pipe which I did think was a little crazy. I hoping the extra 3' of pipe will give me the needed draft I need.
 
Here's my latest update on my stove. I've add enough pipe to give it a total of 15' which the manual minimally calls for. I probably had 11' when I started. I've also installed a chimney bracket. My draft has improved substantially but I still cannot run this stove with the dampener completely shut down. For the most part when the stove has a good burn going I can bring the dampener down to about 10-15% without having the glass lightly coated with creosote. Maybe with dryer wood that wouldn't be an issue but it is what it is with wood only cured for 1 year.

I would like to hear from someone else running a Jotul F400 to compare with.
 
Good to hear there is progress. Many EPA stoves would be unhappy with just 11 ft of flue.

10-15% open is about what I experienced when burning hardwood except in very cold weather when draft was stronger. This will vary with the wood species and wood moisture content. With doug fir I could close the air all the way down, but not with locust.
 
Here's my latest update on my stove. I've add enough pipe to give it a total of 15' which the manual minimally calls for. I probably had 11' when I started. I've also installed a chimney bracket. My draft has improved substantially but I still cannot run this stove with the dampener completely shut down. For the most part when the stove has a good burn going I can bring the dampener down to about 10-15% without having the glass lightly coated with creosote. Maybe with dryer wood that wouldn't be an issue but it is what it is with wood only cured for 1 year.

I would like to hear from someone else running a Jotul F400 to compare with.
F500 here. Kind of a standard start up here includes a final close of the damper down to about 10%. Less than that will shut off too much air and get what you describe with clouding glass. Above that will allow the stove to run hotter. Except - we almost always shut it down to 10% or so, but outside temps influence the heat output also. Warmer outside temps, less draft, lower stove temps. Colder outside temps, more draft, higher stove temps. So leaving it turned down supplies ample heat in a lot of different conditions.
 
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Maybe with dryer wood that wouldn't be an issue but it is what it is with wood only cured for 1 year.

Why not try using a couple of 2x4 scrap lumber (not enough to overfire) which you know would have low moisture and see how that affects your damper setting. Just a test, but if you think its the wood moisture that's holding you back, try this and then you know going forward for next year if that was the main issue. Otherwise it may simply be a stove limitation in your setup that keeps you at 10% minimum.
 
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It's not really a limitation, it's a variable. Every fire will be different as the wood and outside temps change. Leaving the air control open just a little is fine.
 
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Then it sounds like I'm doing pretty good. It's warmer now and with the coming of spring I'll have to wait till the fall for further burns. One thing that has change significantly is starting a fire. It's been a lot easier with the added chimney pipe. Another thing I've noticed is the ash is at a minimum with this stove compared to the Jotul 3CB I had before. It did seemed like it took forever to get a good ash bed and I haven't emptied the ash pan yet and it's been a little over a month since I started this post, granted some days I kept the stove running as low as I could just to keep the fire going. I'm glad I upgraded even considering the added unexpected expense of upgrading my chimney. I think I will be a lot happier next season with this stove.

Thanks again for everyone's help and suggestions!
 
We rarely blacken the glass anymore. But back in the day, we would blacken the glass every weekend. Thought it was just going to be that way. Found a great chemical cleaner, and kept it clean, as we love the fireview.

But now today, we rarely blacken the glass. After a few weeks, maybe bit of white hase. That cleans up with a wet paper towel. What happened. The secret is. Yes better 3 year old seasoned oak wood. And how we burn. We start cold stove and burn fires that get the stove to 400F for a few reloads. To do this with a cold Oslo, cast iron stove takes 3-5 reloads This develops a 2" bed of red coals. With the bed any wood added will burn well, no smoldering So then we can cool it down. The bed of coals will not blacken glass. A few weeks ago, we did wake up to blacken glass. What happened, we added a few splits in the middle of the night choked the air before they got going, without a bed of coals. In the morning we found half burned splits and blackened glass. I burned hot for a while and burned the glass clean.
 
I just picked up a used Jotul F400 that looks like it is in Great condition. Fired it up for the 1st time and everything seemed okay. Loaded it up after a couple of hours and set it on low. Went out to dinner came home 5 hours later and noticed the glass was almost completely black and what wood that was left in the firebox was pitch black also. What the heck is going on?

I don't know what is causing your stove condition, but I have always had to clean the glass regularly on my F400. I can burn bone dry wood, but, I always find some residue (usually black or dark brown) at the lower corners and some whiter ash residue toward the middle. I think this stove is more particular about draft (and some other conditions) than many stoves from what I have read and my draft (chimney height) could be better.

Anyway, still an awesome stove IMHO.
 
Sounds like we have the same stove for sure. I've come to the conclusion the chimney height was my main problem AS PER the manual specs. My wood is another problem at 23% but not as big an issue as was the draft with a short chimney I started out with.
 
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