# Jotul 118 Efficiency



## brianbeech (Feb 7, 2011)

I've got the "old school" 118 from Jotul and I absolutely LOVE it.  Suffice it to say that I am now fully addicted to burning wood inside of a wood stove.  I liked burning wood before, but now that I've got a stove, it has been taken to a whole new level.

Anyway, I was curious about how efficient my old stove is.  I know that I don't have the secondary burn, but I tend to believe I'm really getting some good efficiency out of it - when I finally burn it correctly.  It seems that when I'm in the 200-450f mark, it is a typical inefficient beast, but when I get up to 500+f, I don't see any negatives and this thing is throwing out the heat and I barely see any smoke coming out of the chimney.  I'm assuming this is a good thing?


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## begreen (Feb 7, 2011)

The less smoke out of the chimney the more efficiently the fire is burning. With a modern epa stove that is typically no visible smoke once the stove is hot. The original 118 did a bit of a reburn with air leaking in from the dial wheel air intake. This has an upper and lower slot. I am guessing that the upper slot is to inject a little air high enough to mix with the gases making the trip around the baffle. Precaud, is that a correct assumption? 

But there is also heating efficiency. This is where the 118's upper chamber really helps. It scavenges heat off the flue gases as they travel the length of the chamber and greatly increases the radiant surface for this heat to be released into the room. The trick is to keep it hot enough for a clean burn. It sounds like you are starting to get it dialed in nicely.


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## Peter B. (Feb 7, 2011)

It's very easy to add secondary 'plumbing' to the 118 if so desired.  I did so with a friend's way back in 1989, and as I recall, some secondary combustion was achieved, though I might now alter the design I used then.

Peter B.

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## brianbeech (Feb 7, 2011)

BG, I think I AM finally getting a hold on how to burn this stove.  I read a post a while back about leaving the stove alone - now that I'm able to do that, I see some really good burn times (relatively) with the stove staying around 550f for hours on end.  I think when I finally get some good seasoned wood I'll be seeing some higher temps and I'll be able to get longer burn times too.  I CAN'T WAIT!  The upper chamber was rather intruiging to me, glad to hear some theory on how it's used.  Keeping the stove hot enough for a clean burn can be a challenge when you have wet wood.  Oh, next year will be so fun!

Peter, I'm assuming I'd have to make some structural changes to the stove?  Unless there is a plate that can be fashioned to fit the side flue outlets, I doubt I'd do any drilling on this baby.  It's a good looking stove and if I ever decide to replace it, I'd just give it back to my neighbor.


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## Peter B. (Feb 7, 2011)

Because it was (only) an experiment (and my friend felt the same way about drilling or modifying the stove's exterior), I drilled through the stove pipe just above the outlet flange in use and ran some 1" copper through the pipe, then down into the stove... obviating any 'scars'.

I'm not advocating similar, just saying it's eminently possible.

Yes, if it was a permanent installation, I would have made a plate to replace one of the unused flue outlets... and employed something more durable than the copper.

But it was a fun experiment.

Peter B.

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## begreen (Feb 7, 2011)

Yes, with an almost virgin, enameled 118, I wouldn't go about modifying it anytime soon. That is almost a museum piece it's in such nice condition. It's great to hear that it's giving you so much pleasure.


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## gpcollen1 (Feb 7, 2011)

Burning good wood in that thing will produce a ton of heat.  We had one in teh late 80s and 90s in a very drafty old farmhouse and it kept the place warm for sure...


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## bgman (Mar 1, 2011)

I have a scandia  stove like the 118 cb. I bought it used and it was probably at least 10 years old. I've been using it in my basement for the past 8 years. The house is a 2400 sq ft ranch ( basement is 70' long)  I leave the basement door open and have cut 12"x4" grates in 3 rooms. I try to cut all logs to 24-25 inches. At bedtime 12:30am I fill the stove with split wood fitted tight and there will be a nice bed of coals in the back at 7:15 when I get up. I will combine red oak and maple to get a clean hot burn. I clean the 5" flue every 2 weeks and the chimney every 4 weeks. Creosote build up is minor but it just drafts way better clean. Been thinking of putting a 6 "dia pipe and would probably not have to clean the pipe as often. The stack temp will easily go over 1000 degree if I let it. I run the stove inlet a little more than 1/4 open and pipe damper 1/2 open with stack temp running about 600-300 as wood burns down. When home I stoke stove(not full) every 4 hours. The t stat in living room is set at 68 and the boiler will start every 1 1/2- 2 hours at outside temps 15-30 degrees. Bought this stove for $50.00 and like it so much I bought another on C/L last year that was NOS. The original cast side plates over the years have warped, so I made new ones out  of 1/4" diamond plate and cut 4 rectangular holes to allow flame/ heat to hit the sides of the stove. If anyone is using 6" pipe out of stove, how often do you clean it?


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