Jotul 118 burning

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Battenkiller said:
Hey, Brian. I found this one for you on my first try:


http://www.kschimney.com/store/product.php?pid=210

I meant locally. :) EDIT: apparently you meant pretty locally too - just found out where K's is. But thanks, if I strike out locally I'll be ordering one online! I'm a man, so instant gratification is something I war against. :) I'd HATE to wait days for something to ship; like a child on Christmas morning.

I hear those baffles on these stoves can be expensive, I'm hoping that mine don't go bad anytime soon. With what I've spent on fuel oil so far this year, I'm running out of fun money.
 
BK, looks like I'll either be driving to Jasper or ordering one. Went to Home Depot, Tractor Supply Company, PC Lumber, and a place called Fireplace Solutions, who didn't want to have the door unlocked or answer the phone, and none of them had 5" pipe. Two had flue dampers in 6" and 8". Darn, now I get to wait wait wait. Fun! Get get a thermometer for the flue though. =D
 
Waiting in this case is a good thing. Take advantage of the time to learn more about the stove. The more you know about how it behaves under varying conditions without the damper the better. It will help guide you about the effect of using the damper. Try moving the thermometer back and forth between the stove top and the flue pipe to correlate how hot the stove is vs how hot the pipe is getting. Let us know what you are reading at various points in the burn.
 
BeGreen said:
Waiting in this case is a good thing. Take advantage of the time to learn more about the stove. The more you know about how it behaves under varying conditions without the damper the better. It will help guide you about the effect of using the damper. Try moving the thermometer back and forth between the stove top and the flue pipe to correlate how hot the stove is vs how hot the pipe is getting. Let us know what you are reading at various points in the burn.

Will do - I've got a stove top thermometer and I just purchased a flue thermometer and will have them both on. I'll do some tests tonight and log some data to see how it goes through the burn. Thanks all.
 
how many sq ft are you heating with that stove?
and what have you outside temps been?

just wondering, I might be getting one of those stoves too. might be the newer one, but should be some what simaliar.
 
Lynch said:
how many sq ft are you heating with that stove?
and what have you outside temps been?

just wondering, I might be getting one of those stoves too. might be the newer one, but should be some what simaliar.

I've only burned it twice, but it is in an unfinished basement of approx 1300 sq.ft. I'm hearing that it would easily heat the open space in the basement if my walls were insulated - not sure how this is going to work with uninsulated cinderblock walls. When I get the stove running more than 4 hours, I'll let you know how it heats during what temps. I am at a couple of distinct disadvantages in that I don't have 'seasoned' wood this year and the lack of insulation on my walls. Either way, I'll report back in the next day or so. I CAN tell you that this stove lights easier than anything I've ever tried to start.
 
Alright! Burned this evening and it is still burning at 11pm. Began around 5:15pm. So I've had about 6 hours of burn time now with a stove top thermometer and a flue thermometer. Here's what I can say so far:

First, this stove is awesome! I finally got it up to temp by turning down the air and adding wood. Got up to 650f. Get this! Flue temp was around 325f. I'm seeing about half the temps on my flue as I am in the stove - and it's pretty consistent across the temp ranges. So when I dropped to 500f I was literally right around 250f on the flue.

I'm guessing this is a good thing and it's making me pretty happy that I don't need a flue damper; just don't need any more confusion to the mix. The wife could run this stove if what I'm seeing now is the right way to run the stove.

As far as the heat output, I'm a bit disappointed. Don't get me wrong, this stove cooks, but in the extremely drafty, walk-out, uninsulated basement, I'm not realizing any heat more than about 4'-6' away. It looks like I'll be doing some serious insulating of the basement - which will amount to practically finishing the walls.

I do believe that once I've stopped the drafts in the basement that I'll really see some heat down there that will probably translate to a warmer second floor. I'm excited, but my excitement is really for next year when I've got seasoned wood and an insulated basement. I don't see fuel oil prices dropping anytime in the near future, so I'll continue down this path. Of course, it's rather enjoyable and I could see it becoming a hobby.

Run this is the basement and then pick up a Morso 7642 upstairs for the living room and I think I'll be set. :D
 
Even without the insulation, you'll start to see an improvement in the room temps you as the basement starts to store some heat. Keep it burning hot for a couple of weeks and things will start to look up. No substitute for insulating, though. At least a third of your heat can flow into those uninsulated walls. Plan the walls and insulation today. I used that same stove here the year we moved in and it did nothing but leave us freezing upstairs until we got the insulation done. Night and day difference afterwards. Haven't used the electric baseboards here in 20 years now, except for emergencies and when we are out of town. 2x4s, fiberglass, and sheetrock are cheap compared to oil. They'll pay for themselves the first year.

Get a cheap IR thermometer from Harbor Freight or similar place. Use it to check the accuracy of your thermometers, but also to shoot the surrounding area for surface temps. You will learn a ton about where your heat is disappearing to.

One thing I should warn you about is the 8x8" flue. They have an ID of about 7", for a cross-sectional area of 49 sq.in. A 5" round pipe is only 19 sq.in. When your hot gases expand inside that flue, they will cool to roughly half of what they are in the 5" pipe, and get worse as they rise. Don't go chucking that stove full of extra-dry wood and choking it down too much or you will end up with a massive creosote buildup in no time. I did that many years ago for an entire season burning pallet wood. Driest stuff I've ever burned, totally nuclear unless I smoldered it to control it. Towards the end of the season I started to get smoke back up into the room even with the key damper completely open. The following fall the sweep pulled out about 15 gallons of the stuff. The flue was nearly plugged solid about halfway up. Lucky I'm still here.
 
you’ll start to see an improvement in the room temps you as the basement starts to store some heat.
That's a bit optimistic, methinks. I've never met a basement that does that without huge quantities of btus being stuffed into them. They're great thermal sponges.
 
Agreed. I don't think of basements as heat storage. However, I could see it working moderately well in a basement with good convective venting to upstairs -and - fully insulated walls.
 
Well, after living with this type of setup for 20 years now, I'll have to respectfully disagree with both of you. Theoretical heat losses are not the same as observed heat losses. Same with stoves, that's why they are tested in labs to get the true nature of their burn profiles.

There are numerous reasons why a basement will hold a lot of heat. The "sponge" theory is just a mental construct. Heat gets transferred at a situation-specific rate, it doesn't get sucked away as fast as it is produced. Cement block does have insulating properties. An 8" 3-core block made with a cinder aggregate has an R-value of about 1.7. Many newer basements use insulating concrete forms that are left in place after the concrete is poured. Even the soil itself has insulating qualities, especially if it is high in organic matter. Undisturbed soil will gradually develop air channels and decaying root material from grass growing in it over the years. These significantly impede heat flow through the soil.

Many slabs now are being poured with foam board underneath. Even without the insulation, the contact between the concrete and the gravel below is very imperfect, with the gravel settling slightly and getting pulled away from the slab in numerous spots, creating millions of tiny dead air spaces. Plus, the dear air spaces within the gravel fill itself provide a degree of insulation. Dead air is one of the most effective insulators on the planet.

Even very small spaces can seriously impede heat flow. In spite of the smooth texture of finished soapstone, folks here are reporting a 50-100º temperature differential between cook stone temps and the other side of the stove top, even after hours of steady burning. I personally measured a 50º temp diff between the two sides of a Fireview top at the Woodstock factory, some 8 hours after the stove was first fired. That's why they use thermally conductive paste in the heat sinks use in the electronics industry. If mass alone provided the most effective heat sink, there wouldn't need to be cooling fins and fans sitting on top of the aluminum heats sinks in computers. Just use a more massive block. In practice, the cooling fins create a a steeper temperature gradient across the thickness of the heat sink, so heat flows much faster than using the heat conductance of the material alone.

Aside from how significant any of that is, I only have to look at the measured temps in my home to convince me. Right now, my stove is a uniform 105º, while the floor surrounding it is still 96º - 12 1/2 hours after I filled it last night. I shot the floor last night with the IR gun and is was about 160º. That can only mean that the stove cooled down a lot faster than the floor did, even though it still has some active coals in there. The upstairs temp was 72º last night, it's now 68º. Outside temp has finally risen to 20º. Seriously, is that 105º stove down there putting out enough heat by itself to warm the entire upstairs here through convection from the stove alone? Why, then, will it take all day for me to get this place back up to 72º again, when the stove will start to put out massive quantities of heat almost immediately after startup? The reason is that heat is being pumped into the basement walls and floor and being stored there. It is so extremely capable in regulating the temps in my home that I have to remember to start a fire most days because the temp stays basically the same throughout the entire house.

Yes, there are a lot of heat losses from an uninsulated basement, but in real life, they turn out to be less than you might think at the end of the day, and the benefits of mass heat storage more than compensate for the losses involved. Personally, you can have your convective space heaters in your living spaces, and the ups and downs of home temperatures throughout the burn cycles that come with them. I much prefer the stable temps I get from the basement installation and opt to just burn a little more wood to overcome the heat losses. One complete day spent here has made many a convert.
 
i agree!

b/c my dad heats his home with 2 stoves one in the basement and one on the 1st floor

and with out the basement stove there is a pretty big difference in the heat.
i cant give you numbers and temps but you can walk around bare foot and and feel warm.
plus it has to help dry the wood even more with all that heat in the basement near the wood.

and i agree with alot of heat being lost in just heating a space that is rarely used or even visited, unless to tend the fire.
But having warm floors and a few vents in the floor make a big difference.
 
I respectfully disagree. Personal experience in this case seems subjective. It's good that it is working well in your case, but this can vary dramatically with different environments.

First, many of the folks here are not in modern houses with isolated slab floors or insulated block construction, or even 3 core block walls. The heat loss via the walls and slabs in conventional construction (say up until the past 20-30 years) is a common case and the losses are significant. You should be able to derive test data on that if you look for it. I know I found some on the HVAC sites for heat loss calcs a while back. Second, many folks here do not have good heat transfer from the basement to the upstairs and do not see this benefit.
 
Well, I finally went down at 3:00 and started the stove. I was getting nervous. Upstairs temp never budged from 68º the whole time, I thought I was hallucinating or sumpin'. 16 hours of stable heat, and I don't think much was coming from an inactive stove. Now I'll have to run it a little harder to make up for the heat I lost earlier today.

Stove was 98ºF, the floor way underneath was 105º. The floor was actually warming up the stove at that point. Coldest floor temp was 55º - in the farthest corner from the stove - but the rest of the floor felt nice on my bare tootsies.
Insulated walls were down to 67º, non-insulated storage room walls were 58º. 9º difference. Big deal.

The heat built up rapidly in the basement soon after I got the stove up to temp. I can feel heat come up at the top of the stairs, but ironically, the place just dropped a degree during the last 45 minutes of hard-running stove time. Figure that one out.

Over and out.
 
BeGreen said:
I respectfully disagree. Personal experience in this case seems subjective. It's good that it is working well in your case, but this can vary dramatically with different environments.

First, many of the folks here are not in modern houses with isolated slab floors or insulated block construction, or even 3 core block walls. The heat loss via the walls and slabs in conventional construction (say up until the past 20-30 years) is a common case and the losses are significant. You should be able to derive test data on that if you look for it. I know I found some on the HVAC sites for heat loss calcs a while back. Second, many folks here do not have good heat transfer from the basement to the upstairs and do not see this benefit.

well, i respectfully disagree too, it does have its benifits.
 
Anyway, back to the OP... The question isn't if, but how. His stove is already installed down there, so it's gonna be there for a while. Let's all chip in and help him get the most heat into the living space. If he doesn't notice any improvement at all after a couple weeks steady burning, he'll need to at least put something up against the walls.

Just standing up the sheet rock (unless he plans a horizontal installation) he intends to use against the wall will create a dead air space behind it that will cut down on some of the heat loss. Personally, if I was going to do this place again, I'd use two layers of 5/8" rock. Gypsum has a fairly high specific heat capacity, so he'd get more heat storage, and it would be on the warm side of the basement wall, with insulation behind it.

Any other helpful thoughts?
 
First, BK, you, my friend, are the master of mental constructs, not I. Perhaps you have a magical basement.

My house has a full daylight basement under, where my lab is. It is a massive concrete pouring, some places 5-6 feet thick. Insulation varies from R4 to R8, averaging R6. All the windows have R8 over them in the winter. Every weekday I go down and light the Nestor Martin. I typically burn 2-3 loads during the workday to get it in the low-mid 70s. On Mondays, when no fire had been lit over the weekend, it is 55F down there. On days when a fire had been lit the previous day, it is 58-59, maybe 60 if its not cold outside.

Based on those numbers, I see little retention of heat. Almost everything I put into it during the day is absorbed by the next morning. Hence my description of the basement as a thermal sponge. It does a great job of wicking btus into the earth. The only way to get any retention to speak of would be to feed it constantly.

Does it impact the comfort levels upstairs? Absolutely. On weekends, when the basement is cold, the upstairs floor is definitely colder feeling, and the heat loss into the evening is definitely more rapid. But - the difference is not enough to justify keeping the basement warm. Maybe it takes one more log in the upstairs stove to make up for the temporarily warm basement's contribution. And that is where the inefficiency shows.

It is always going to be more efficient to have the stove be located in the occupied space.
 
Nice stove! I'm envious - this is the model I wanted but wouldn't fit in my limited space.
 
Already I'm beginning the basement insulating. Deciding to do this has not hampered my burning this year, I'll be burning as much as possible as long as I still have wood. Stove has been getting in the 5-600f range and flue sitting right around 250-300f. This house was built in the mid 30's, so whatever new concrete block insulating properties exist, you can be my house has none of them. :) I'll be putting up R10 foam board, studs and then drywall. I'll start on the exposed portion of the basement (walk-out) and slowly move to the front. You can definitely feel lots of cold coming THROUGH the blocks. Touching the wall proves it to be sending lots of cold in. I think if I heat the stove up and keep it that way for a couple of days (which is hard when I'm gone all day to work), I believe I would see some noticeable differences. I definitely will be keeping this stove hot all weekend and we'll see how 3 days of heat does.

Thanks dvellone - when my neighbor showed it to me I was pretty enamored with it. Then to have him just GIVE it to me! WOW!
 
precaud said:
First, BK, you, my friend, are the master of mental constructs, not I. Perhaps you have a magical basement.

So I take it you're going to disrespectfully disagree with me? :smirk:

That's OK, I can handle it. You're in New Mexico and I'm thousands of miles away in New York. And there are billions of Internet miles between us.

Have a nice day. :)
 
Calm down, guys, or I'll send you a gift subscription to the New York Times...
 
Battenkiller said:
So I take it you're going to disrespectfully disagree with me? :smirk:

No disrespect intended at all. We're drawing quite different conclusions from different sets of experiences. It isn't the first time that's happened. Not a big deal.
 
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