Another help me choose add on furnace

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True...but I would think when most people are asking about burn time, they mean when its really cold out...in other words, when its -20*F out, am I gonna need to get up in the middle of the night to feed this thing to keep from freezing to death in my sleep?! ;lol

I would disagree. Most people want to know the maximum burn time which means at the lowest possible clean burn rate so that the house temperature might fall but so it doesn’t fall too much and you can just reload and go! Has a lot to do with how long you’re away from home for work and sleep.

It’s a hugely important performance specification of any solid fuel burner and completely independent of the house heat demand.

Wouldn’t it be great to have a wood furnace as large as the max caddy but with a low burn rate for 24 hour burn times and still the ability to efficiently blow the same wood load on 3 hours?
 
That's crazy to have 2x4 construction where you are wow! You are making a good case for the tundra, and thank you for reaffirming the Heatpro would be too much for the house.

This might help you figure out what to expect: our coldest night -15f (-26 celcus) kept easy 75f on 3/4 quarter load. After 8 hour reload house was still 70f. If I were to have waited till the 10 hour mark I'd expect the house to be around 65f in that weather. I'll have to wait till it gets cold again to find out what burn times I get if I fill the box right full.

And for what iv been hearing the Kumma, (having a slightly larger firebox) would be able to add a couple hours ontop of that burntime. The question you will need to figure out is if it's worth the extra 3 grand.
 
Most people want to know the maximum burn time which means at the lowest possible clean burn rate so that the house temperature might fall but so it doesn’t fall too much and you can just reload and go! Has a lot to do with how long you’re away from home for work and sleep.
Not entirely different from what I said.
The tundra is computer controlled dampener right? Or is it manual?
Basically manual...can hook a Tstat up though...there is a computer, but I'm not sure what all it is involved with, blower control for sure...probably high limit controls too...I'm pretty sure it is not involved in the everyday go-ins on of the damper.
But it is pretty easy to "computer control" them, right @Case1030 !? ::-)
 
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And for what iv been hearing the Kuuma, (having a slightly larger firebox) would be able to add a couple hours ontop of that burntime. The question you will need to figure out is if it's worth the extra 3 grand.

The extra $$$ doesn't just get you that, it's the completely automated computer control of the fire. In just a few minutes I can go from lighting a fire in a completely cold firebox to walking away and leaving it completely unattended for the rest of the burn knowing the fire will be burning -optimally- throughout the full burn cycle. Heck, even my GF can light a fire from scratch with it and she's never ran a wood fired anything in her life. The only learning curve is knowing how much wood to load for the weather. This is in addition to it being hand built in a small factory in N MN by a company who pays good wages to their handful of employees. To me this is worth something and something I'm willing to pay more for.

Having said that I've actually got to go downstairs now and start a fire in a cold firebox. :)
 
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The extra $$$ doesn't just get you that, it's the completely automated computer control of the fire. In just a few minutes I can go from lighting a fire in a completely cold firebox to walking away and leaving it completely unattended for the rest of the burn knowing the fire will be burning -optimally- throughout the full burn cycle. Heck, even my GF can light a fire from scratch with it and she's never ran a wood fired anything in her life. The only learning curve is knowing how much wood to load for the weather. This is in addition to it being hand built in a small factory in N MN by a company who pays good wages to their handful of employees. To me this is worth something and something I'm willing to pay more for.

Having said that I've actually got to go downstairs now and start a fire in a cold firebox. :)

Your right I took for granted the tempurature controller that moderates the heat output was a tool I added on to my tundra to allow load and go. Doesn't cost much about $60.
 
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Dont get me wrong if I could of bought a new Kumma for a price I was willing to spend I would have. But with exchange rate Cad/Usd and shipping it wasn't and option at the moment. Those extra features are nice.

As the tundra sits it's all manual. With little modification you have the capability to load and go. Like a knock off kumma.
 
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It obviously works and improves the Tundra, but controlling it via flue gas temps is not quite the same as by firebox temps. I monitor all sorts of temps (including firebox temps with a MYPIN wired to the factory thermocouple connected to the computer) and the flue/firebox temps are not locked to each other. It's actually kinda cool to sit and watch how the firebox/flue temps relate to each other. At times one can be going up while the other is going down and visa versa.
 
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It obviously works and improves the Tundra, but controlling it via flue gas temps is not quite the same as by firebox temps. I monitor all sorts of temps (including firebox temps with a MYPIN wired to the factory thermocouple connected to the computer) and the flue/firebox temps are not locked to each other. It's actually kinda cool to sit and watch how the firebox/flue temps relate to each other. At times one can be going up while the other is going down and visa versa.

I understand and agree with what your getting at. That means a cleaner burning stove. Very impressed that a small family owned company can get done what large stove manufacturers can't.

At least with the 2020 emissions I expect more companies will be coming up with similar clean burn technology.

You do get what you pay for, and with the funds I saved by purchasing an economy furnace that still performs upto my expectations and needs. (Paid $1800 CAD for Tundra 2)

Just for speculative sake if I didn't already own the following, I'd be able to buy a 20 ton gas log splitter, huaquavarna 372xp, sthil ms290, and cover the 16 foot chimney for the Tundra. If my math is correct, I should still have a bit of cash left over. For some one just starting out burning wood that's exactly what would help a guy get a good start.
 
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Speaking of cleaner burning.

Just went to see if the EPA released a new list of the certified furnaces yet as they did recently release one for stoves. Looks like they haven't, as they still show the June '18 one as the latest. Anyway, looked at the results a bit closer and something surprised me. With all the negative real-world reviews of the Hy-C furnaces, they actually tested out 2-4 times CLEANER burning than SBI's lineup even though they are not nearly as efficient. SBI's furnaces tested out among the 'dirtiest' of the whole group. Very strange. :confused:


EPA.JPG
 
Speaking of cleaner burning.

Just went to see if the EPA released a new list of the certified furnaces yet as they did recently release one for stoves. Looks like they haven't, as they still show the June '18 one as the latest. Anyway, looked at the results a bit closer and something surprised me. With all the negative real-world reviews of the Hy-C furnaces, they actually tested out 2-4 times CLEANER burning than SBI's lineup even though they are not nearly as efficient. SBI's furnaces tested out among the 'dirtiest' of the whole group. Very strange. :confused:


View attachment 235990

Efficiency and emissions are not directly related. There are many low emissions and low efficiency wood burning devices. It’s great when you can have high efficiency and low emissions.
 
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Speaking of cleaner burning.

Just went to see if the EPA released a new list of the certified furnaces yet as they did recently release one for stoves. Looks like they haven't, as they still show the June '18 one as the latest. Anyway, looked at the results a bit closer and something surprised me. With all the negative real-world reviews of the Hy-C furnaces, they actually tested out 2-4 times CLEANER burning than SBI's lineup even though they are not nearly as efficient. SBI's furnaces tested out among the 'dirtiest' of the whole group. Very strange. :confused:


View attachment 235990
They (HY-C) must have run them balls out to get them that clean for the test...but then when people try to run them more realistically...puff the magic furnace.
I did rifle through the EPA test report on the FC's a while back, and they did have some pretty short burn times...
 
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Efficiency and emissions are not directly related. There are many low emissions and low efficiency wood burning devices. It’s great when you can have high efficiency and low emissions.

I understand that, I'm just surprised the SBI's stuff is many times "dirtier" than those o so well designed Hy-C's. ;lol
 
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They (HY-C) must have run them balls out to get them that clean for the test...but then when people try to run them more realistically...puff the magic furnace.
I did rifle through the EPA test report on the FC's a while back, and they did have some pretty short burn times...

I guess that would make sense.
 
I didn’t realize the efficiency of the Caddy and VF100 were that close. I always thought the VF’s were a lot more efficient. The VF definitely has the edge when it comes to emissions though.
 
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I didn’t realize the efficiency of the Caddy and VF100 were that close. I always thought the VF’s were a lot more efficient. The VF definitely has the edge when it comes to emissions though.

The vf is very clean and pretty efficient.
 
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I didn’t realize the efficiency of the Caddy and VF100 were that close. I always thought the VF’s were a lot more efficient. The VF definitely has the edge when it comes to emissions though.

Same here didn't realize that ether. I thought the Vapor Fire would have had at least a 10% if not more efficency advantage over the Tundra.

I honestly believe the only way Sbi will come close to meeting the 2020 emissions will be removing the fire picture window and insulating the door to increase firebox temps.

I know this might be off topic for this thread but when it comes to emission standpoint, remember when the new DEF systems first came out... burn more diesel to burn cleaner exhaust.
 
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Same here didn't realize that ether. I thought the Vapor Fire would have had at least a 10% if not more efficency advantage over the Tundra.
I was thinking about this last night after my post. I wonder what it would take to get a cord wood furnace in the 80% efficiency range with emissions low enough to meet the 2020 regulations. The boiler guys have had lambda controlled cord wood boilers for years now that have efficiencies over 80% maybe even 90%. I'd assume it is tougher to do in a furnace since you possibly can't have a downdraft design with a furnace. Maybe @lampmfg can give some insights on this.

I know this might be off topic for this thread but when it comes to emission standpoint, remember when the new DEF systems first came out... burn more diesel to burn cleaner exhaust.
International Harvester knows how that panned out. ;)
 
I was thinking about this last night after my post. I wonder what it would take to get a cord wood furnace in the 80% efficiency range with emissions low enough to meet the 2020 regulations. The boiler guys have had lambda controlled cord wood boilers for years now that have efficiencies over 80% maybe even 90%. I'd assume it is tougher to do in a furnace since you possibly can't have a downdraft design with a furnace.

Easy. The stoves, some not all, have been over 80% for decades. Catalysts. That’s the future. Just like your car.
 
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Easy. The stoves, some not all, have been over 80% for decades. Catalysts. That’s the future. Just like your car.
I had a catalytic wood stove. No thanks. I’d take less efficiency over that any day of the week.

I want something that is controlled by a computer ( lambda ) and that is smarter than what I am when it comes to burning the cleanest.
 
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I keep hearing about the new 2020 regs coming out on wood furnaces. IF they were to take effect (I just heard they are trying to push for 2 more years) would it be the 1st if the year they take effect? I am just wondering if that happens what will others besides Kuuma do? Or do you think they have furnace technology ready just in case the new regs do happen?
 
that's blasphemy for some on this site! ;lol
If I was purchasing a wood stove I would most certainly want a window, as it would be almost a piece of furniture in my main living quarters. However a furnace will be in my basement only seen by me most of the time. I don't really see the need for a window, except to see exactly what your fire is doing without opening the door. But it sounds as though Kuuma took this guess work out, so I shouldn't have to worry about what the fire is doing for the most part.
 
I keep hearing about the new 2020 regs coming out on wood furnaces. IF they were to take effect (I just heard they are trying to push for 2 more years) would it be the 1st if the year they take effect? I am just wondering if that happens what will others besides Kuuma do? Or do you think they have furnace technology ready just in case the new regs do happen?

As of now the new regs are effective May of 2020 .
 
I am just wondering if that happens what will others besides Kuuma do?

Either sh*t or get off the pot is a term which comes to mind. ;lol

<soap box>
Which brings up another reason why I made the decision I did. This extremely small company seems to be the only one who had the foresight and drive to do what the larger companies couldn't or were unwilling to do and all with a R&D budget minuscule compared to these larger companies. Instead these other companies were/are sitting around selling products in which they knew would eventually become outdated. Now some of them are whining because they don't have "enough time". It's laughable how a little mom and pop shop in the middle of nowhere can do it while these companies "can't". I don't believe it's because they can't though, it's my opinion it's because they don't want to spend the resources to do so. It's a shame guberment has to step in and force these companies to advance/better themselves while a few enthusiasts in N MN made it happen YEARS prior w/o any guberment intervention. </soap box>

==c
 
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Either sh*t or get off the pot is a term which comes to mind. ;lol

<soap box>
Which brings up another reason why I made the decision I did. This extremely small company seems to be the only one who had the foresight and drive to do what the larger companies couldn't or were unwilling to do and all with a R&D budget minuscule compared to these larger companies. Instead these others companies were/are sitting around selling products in which they knew would eventually become outdated. Now some of them are whining because they don't have "enough time". It's laughable how a little mom and pop shop in the middle of nowhere can do it while these companies "can't". I don't believe it's because they can't, it's my opinion it's because they don't want to spend the resources to do so. It's a shame guberment has to step in and force these companies to advance/better themselves while a few enthusiasts in N MN made it happen YEARS prior w/o any guberment intervention. </soap box>

==c

I believe most of the big manufacturers where/are trying to milk every last drop out of the old tech before investing in cleaner burning stoves.