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With that much height you'll be fine with an extra 90...but I would still try to avoid it if possible...use 2 45s instead of 2 90s. Put one 45 at the furnace...run up to the height of the chimney breech, then another 45. That way the only 90 will be at the bottom of the chimney. If you don't have the room to pull that off, meh, don't sweat it, should be OK with 90s (better with 45s though, just to be clear)
And I would still install a baro damper...with that much chimney height you'll have crazy high draft...at least when its windy, if not all the time.


So winter is getting closer to it's end. All that you told me about the Ashley 1440E and U.S Stove came true. What a pile of junk! Firebox cracked in multiple places, would not stop over firing and I could not control it even with drafts. So I looked more into the Kuuma and spoke with Dale on many occasions and jump right into the Kuuma family.

I have a Vapor Fire 100 on the way in about a week. Done screwing around.
 
So I looked more into the Kuuma and spoke with Dale on many occasions and jump right into the Kuuma family.

I have a Vapor Fire 100 on the way in about a week. Done screwing around.
Congrats man! Good job getting in under the wire for the price increase!
BTW...you notice my updated sig line?
 
Congrats man! Good job getting in under the wire for the price increase!
BTW...you notice my updated sig line?

Brenndatomu why did you get rid of your Tundra? Was it giving u problems? Or did the lure of the Kuuma overwhelm you? I must admit I’m tempted by them and their long burn times and fire regulation.
 
Pretty much...:innocent:
My first two stoves never came close to the burn times that they were marketed under. They also always left a heavy bed of coals. Had to constantly stir them with very little BTU value in return.

How will the Vapor Fire differ and are you getting the burn times Kuuma engineers are claiming?

Dale is a breath of fresh air in a world where a product is sold with not even so much as a reach around. These folks are knee deep into customer care/satisfaction.

Thank you for any feedback you can give me before I install mine in April.
 
I'm not sure what real world tests they put the furnaces under or what they consider a burn time. I dont think a burn time means constant steady quality heat for 8 hours.

I don't know anything about the kuuma but for that price and claiming to be the best wood furnace I'd think they would be accurate on their burn times. They also take a lot of the operator error out of wood burning.

Did they reccomend what wood to use and split size?

I'm having that issue with my new furnace I split all my wood smaller for my old furnace and I think its reducing my burn times.
 
I'm not sure what real world tests they put the furnaces under or what they consider a burn time. I dont think a burn time means constant steady quality heat for 8 hours.

I don't know anything about the kuuma but for that price and claiming to be the best wood furnace I'd think they would be accurate on their burn times. They also take a lot of the operator error out of wood burning.

Did they reccomend what wood to use and split size?

I'm having that issue with my new furnace I split all my wood smaller for my old furnace and I think its reducing my burn times.

I certainly can understand your frustration, heating ones home with a wood furnace is a very physical and exhausting experience. Nevertheless I totally enjoy every aspect except the over stating what the products capabilities are, then struggling to teach every one in the home how to use it.

I am on my 5th stove move in and out of the basement through a bulkhead because of each of the furnace manufacture has steered me wrong. It has been quite costly and time consuming. The wife has nearly reached the end of her rope with my obsession to burn. The "Vapor Fire" is my last opportunity.

I certainly am hoping this next furnace "Vapor Fire" is everything Kumma claims.

Dale has told me directly as he does with every customer that it can be fed with 20" wood between 18 - 28 % moisture content. Each species of wood will obviously produce it's own BTU value. If I am not mistaken I believe it is the trees with tight fiber strands perform better.
 
I loaded my Kuuma at 11pm last night. Didn't fill it all the way since it was in the 20s overnight. The fan was still coming on most of the morning. Added a little more wood at 10:30 this morning.

I think the thing that helps the Kuuma give even heat is that at the end of the burn cycle, the computer opens the draft to help get heat from the coals. Yes, it'd be even more effective with a way to agitate the coals and bring them forward towards the air vents, but that'd be a much more complicated system.

Now, I will say that the experience Dale relayed about filling the furnace at 5pm and not adding wood again until 10am (17 hours later) has not been my experience. I think that's perhaps because they only heat their shop to 45-50 degrees and pretty much only run the furnace on low. It takes a lot more heat to bring my house to 70+ degrees, so at least thus far I've been running at medium or higher overnight.
 
I loaded my Kuuma at 11pm last night. Didn't fill it all the way since it was in the 20s overnight. The fan was still coming on most of the morning. Added a little more wood at 10:30 this morning.

I think the thing that helps the Kuuma give even heat is that at the end of the burn cycle, the computer opens the draft to help get heat from the coals. Yes, it'd be even more effective with a way to agitate the coals and bring them forward towards the air vents, but that'd be a much more complicated system.

Now, I will say that the experience Dale relayed about filling the furnace at 5pm and not adding wood again until 10am (17 hours later) has not been my experience. I think that's perhaps because they only heat their shop to 45-50 degrees and pretty much only run the furnace on low. It takes a lot more heat to bring my house to 70+ degrees, so at least thus far I've been running at medium or higher overnight.

Your comments are encouraging. I would not expect to get 17 hr burn times. That would be one overly engineered furnace.

I will be extremely excited to get 7-8 hr burn times. Work nor sleep would be effected. That right there is my dream furnace. Fingers crossed.
 
even though the volume of the load to be burned might be the same - small splits will be consumed faster due to the larger exposed area created by the increased number of smaller splits to match large splits volume wise.
 
I loaded my Kuuma at 11pm last night. Didn't fill it all the way since it was in the 20s overnight. The fan was still coming on most of the morning. Added a little more wood at 10:30 this morning.

I think the thing that helps the Kuuma give even heat is that at the end of the burn cycle, the computer opens the draft to help get heat from the coals. Yes, it'd be even more effective with a way to agitate the coals and bring them forward towards the air vents, but that'd be a much more complicated system.

Now, I will say that the experience Dale relayed about filling the furnace at 5pm and not adding wood again until 10am (17 hours later) has not been my experience. I think that's perhaps because they only heat their shop to 45-50 degrees and pretty much only run the furnace on low. It takes a lot more heat to bring my house to 70+ degrees, so at least thus far I've been running at medium or higher overnight.

I loaded my Kuuma at 11pm last night. Didn't fill it all the way since it was in the 20s overnight. The fan was still coming on most of the morning. Added a little more wood at 10:30 this morning.

I think the thing that helps the Kuuma give even heat is that at the end of the burn cycle, the computer opens the draft to help get heat from the coals. Yes, it'd be even more effective with a way to agitate the coals and bring them forward towards the air vents, but that'd be a much more complicated system.

Now, I will say that the experience Dale relayed about filling the furnace at 5pm and not adding wood again until 10am (17 hours later) has not been my experience. I think that's perhaps because they only heat their shop to 45-50 degrees and pretty much only run the furnace on low. It takes a lot more heat to bring my house to 70+ degrees, so at least thus far I've been running at medium or higher overnight.


This is what my current furnace looks like after a single season of burning. This thing over fired the first time I lit it, could not control it even with drafts fully closed and flue managed.

It took many burns to just get it to a manageable burn. Friggin wife nearly lost her mind with it. Don't blame her... DANGEROUS!
 

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How will the Vapor Fire differ and are you getting the burn times Kuuma engineers are claiming?
Dale is a breath of fresh air in a world where a product is sold with not even so much as a reach around. These folks are knee deep into customer care/satisfaction.

I'm finishing up my 5th winter of using my Kuuma VF100. In a single word, a resounding yes.

When I was first doing my research I immediately noticed the huge differences in rated BTU output of most everything on the market vs the Kuuma's. It was even worse back when I was looking, as you had Caddy's claiming MUCH higher numbers than they do now after they were tested to a standard. (read post #16 and on down -HERE-). I was pretty sure the only ones being truly honest about their real world output was Lamppa. They had the latest EPA tests to show for it.

When I called and talked to Daryl (the owner) and explained the style house I have (log cabin w/ loft) and how much volume I'd be heating (~32,000 CF), his response was, "good thing it's not any bigger" and he also mentioned how I may have to use some LP when it gets cold if the Kuuma can't do it solo. He never tried blowing steam up my a$$. The past three seasons, when we are home, 99.8% of my BTU's have come from wood. We average less than $5 per heating season in LP usage, based on total number of minutes the LP furnace runs, when we are home. Total BTU percentage from wood varies from 96%-98%, as it depends on how many weekends we are away during the winter.

As far as burn time, yes, they are what they are said to be. Solid fuel heaters will always have a bell shaped ramp up/down period with a time frame in between of maximum output. The automatic computer controlled damper of the Kuuma helps flatten that curve out though. Can load for as little as 2-3 hours of low heat output (~15lbs) or as much as 18-20 hours of low heat output (~95lbs). I've done 18-20 hour loadings twice this winter when I packed the firebox full of Black Locust and left for the weekend. The sole purpose was to keep the LP furnace run time to a minimum while we were gone. On max burn, I find it impossible to get any less than 9 hour burn times out of it with a full firebox. Keep in mind, a typical full firebox of well seasoned, normal sized red oak splits is around 65-75lbs. Those 95lb loads were of some very large splits of black locust (like 15lb splits).

Burn times and how the Kuuma burns the wood and extracts heat from the wood has never been an issue. What I have optimized for our house is to more effectively get those BTU's produced into the house. I believe I am done experimenting now, after only 5 winters. :laugh: I made changes/improvements to the return air and supply air. I added a speed controller to my blower which speeds up and slows down based on plenum temps. This means my plenum temps are always being kept at the max and my blower NEVER shuts off during a burn, only when I have hardly any visible embers left at all will the blower finally shut off at ~96°. This speed controller also allowed me to really slow my blower down, our house heats MUCH better with real slow blower speeds (lower volumes of hotter air). Also did a few other things as well.

Here it is after my tweaks. BTW, after 5 seasons of burning too. :)

DSC00651.JPG
 
Your comments are encouraging. I would not expect to get 17 hr burn times. That would be one overly engineered furnace.

I will be extremely excited to get 7-8 hr burn times. Work nor sleep would be effected. That right there is my dream furnace. Fingers crossed.

If you have tried several furnaces then you know that the heat and burn time will be much different when it's based on the outside temp. Switching from a non EPA furnace to an EPA furnace I have noticed a big difference but I'm still working on those 6 to 8 hours of solid heat output. Yea it still puts out heat once the secondary burn is done but not the same heat. There seem to be a lot of positives to it. I hope you are very happy with your new furnace and it lives up to your expectations because that is a steep price you will have paid. Even if mine has not lived up to my expectations yet, I am producing less emissions as well as no crazy swings in heat and it's much safer. The daka started getting scary I'd load some wood in and 10 min later smell burning paint and I'd go check it out, the flue pipe would be 500 plus. It happened a couple times. If I wasnt home and around I'd have no house.
 
Your comments are encouraging. I would not expect to get 17 hr burn times. That would be one overly engineered furnace.

I will be extremely excited to get 7-8 hr burn times. Work nor sleep would be effected. That right there is my dream furnace. Fingers crossed.

You will be able to work and sleep longer than those 7-8 hours. Jeez, I would have been extremely pi$$ed off if all I saw was 7-8 hours. During ALL 5 winters my loads were as follows; night load was from 10pm to 7:30am (9.5 hours) and morning load was 7:30am to 5pm (9.5 hours). How large the loads were depended on how cold it was outside. They varied from 30 to 60lbs. I then did a small partial load for those 5 hours in between, again, size of load depended on outside temp. This loading schedule heated the house the WHOLE winter for 5 winters, except the two nights this winter I mention below. I know of a guy who did two 12 hour loads most of the winter in his VF100, at least last I heard he did. @brenndatomu

We did have a couple nights of -35+°F temps in which I purposely did four smaller ~4-5 hour loads in place of the two larger 9.5 loads, as I'm able to burn more wood overall per day (which equals more BTUS in the house) when doing numerous small loads.

DSC00768.JPG
The basement temp above is the temp inside my blower box of my wood furnace. It's the temp of my return air being sent through the furnace to be heated.

Over the years I've figured out I can load my furnace based on looking at the day's HDD. When it's warmer I shoot for ~2lbs/HDD. When colder it's more like 2.5 - 2.75lbs/HDD. Those real cold -35°+ days, I was burning 210lbs a day, which is about as much wood as it could possibly consume in a day. If it could consume more I would have burned more. :)
 
I know of a guy who did two 12 hour loads most of the winter in his VF100, at least last I heard he did. @brenndatomu
Yup, that has been my experience...1 to 2 loads per day...mostly 2. Varying load size and load timing to weather, and house temp.
The only time I went to 3 loads per day was when we had a week of real cold weather (I think many of us experienced that system) and it was at or below 0* F for 3-4 days straight. I didn't keep track of my load sizes like @JRHAWK9 does, but I don't think I ever used more than 150# in one day...and I never did set the computer anymore than medium...set on low 98% of the winter.
And we have not supplemented with fossil fuel either...100% wood...house stays between 70-73...71-73 mainly.
Its nice being able to load and go most of the time too...usually have enough coals for a matchless relight...some times I will throw an unlit match on the coals, just to get active flame even faster...mainly to limit "start up" smoking as much as possible.
The reason for the unlit match is it sparks up fast once dropped on the hot coals...gets things going pretty quick...but if I light the match, then drop it in, half the time it goes out before doing its job.
I am on my 5th stove move in and out of the basement through a bulkhead because of each of the furnace manufacture has steered me wrong. It has been quite costly and time consuming. The wife has nearly reached the end of her rope with my obsession to burn. The "Vapor Fire" is my last opportunity.
I know how ya feel, I have been through a few different wood heaters too...started out with a "free" Wondercoal circulator stove, then went to a Yukon Big Jack add-on furnace. Then came the Yukon Husky wood/coal/oil furnace (its technically still hooked up...slated to be gone this summer) Then I tried a Drolet Tundra (liked that one pretty well after some aftermarket control mods)
Then I came across a cheap Kuuma Vaporfire VF200 (the smaller one) and just had to try it out, even though is was likely to be too small for our house. It impressed me once I got everything set up right on it...but only ran it one winter because all my wood ~20 cords is cut to 22"...VF200 takes 16-18" max...one winter of cutting 6" off everything was enough! So it went down the road. Then Dale at Lamppa told me of a VF100 that was only used part of 1 winter and was for sale due to not being big enough for the house it was in...I ended up buying that one...oh and I forgot, my VF200 sold thanks to Dale telling someone that called in looking for a used one about mine being for sale...never even advertised it.
In this same time frame I also installed a Vogelzang stove in the living room fireplace...and then after a couple winters I found a Drolet 1400i insert stove that replaced the VZ (the VZ was a decent stove, just a bit small, and I wanted an insert style stove so I could service the blower without pulling the whole stove out)
The saving grace for me in all this is that I have a basement garage, so all this moving in-n-out has been pretty easy compared to having to deal with stairs...that said...I think my wife is about done with all my changeouts for a while too...last fall she said this better be the last one for a while (referring to the Vf100)...I just grinned and said "yup...for this year" :D
It will be the last though...pretty happy with it...about the only thing I miss on any of the past furnaces is the window in the door of the Tundra...and also the super easy heat exchanger cleaning procedure on the Tundra (Caddy and Max Caddy are the same too)
Bottom line @Nickatnite , you will not regret your purchase...I have only ever heard of 2 people that did, both were trying to heat big old leaky house that were just too much heating load for the Kuuma (and probably any modern forced air wood furnace) I know the one guy went to an OWB, the other I think just went back "payin the man" for gas heat. :surprised3:

Well...that turned into a novel! :omg:
 
Dale has told me directly as he does with every customer that it can be fed with 20" wood between 18 - 28 % moisture content.
Anything 22" and under will fit...20" is optimal. I have wedged a 24" piece in, but you will only get 1 or 2 smaller pieces in if they are that long.
They will burn 28% MC stuff...but it cuts down on the heat output noticeably...stick to 20% and below for best performance.
 
I certainly can understand your frustration, heating ones home with a wood furnace is a very physical and exhausting experience. Nevertheless I totally enjoy every aspect except the over stating what the products capabilities are, then struggling to teach every one in the home how to use it.

I am on my 5th stove move in and out of the basement through a bulkhead because of each of the furnace manufacture has steered me wrong. It has been quite costly and time consuming. The wife has nearly reached the end of her rope with my obsession to burn. The "Vapor Fire" is my last opportunity.

I certainly am hoping this next furnace "Vapor Fire" is everything Kumma claims.

Dale has told me directly as he does with every customer that it can be fed with 20" wood between 18 - 28 % moisture content. Each species of wood will obviously produce it's own BTU value. If I am not mistaken I believe it is the trees with tight fiber strands perform better.

When will the unit arrive? Will be watching this thread to see how it all works out.
 
This is what my current furnace looks like after a single season of burning. This thing over fired the first time I lit it, could not control it even with drafts fully closed and flue managed.

It took many burns to just get it to a manageable burn. Friggin wife nearly lost her mind with it. Don't blame her... DANGEROUS!
Just wow! What a POS!
 
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