Kuuma Vapor Fire 100 in-progress install pics

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JRHAWK9

Minister of Fire
Jan 8, 2014
2,064
Wisconsin Dells, WI
Here are some in-progress photos of my Vapor Fire 100. I have 98% of the wiring done and just waiting for the HVAC guy to make/install the plenum and duct it over to the existing ductwork so I can wire in the powered damper and high temp limit switch. I found a used 40 gallon electric water heater which I cleaned out, removed the heating coils, installed new fittings/anode rod/pop-off & drain valves and have it ready to be connected to the water coil on the Kuuma. Also have everything wired and set for the humidifier I'll be installing on the plenum. Daryl has been a tremendous help and the build quality of the furnace is amazing. This coming winter and all future winters will be completely different than what we are used to.....which was burning 4+ cords of wood while still using ~$2,000 worth of propane a year all while keeping it 50°-52° at night & when at work. Then having to build a fire in the fireplace after getting home from work to "heat" the house while we were home. Repeat every day throughout the winter. It sounds a bit crazy, but I've been excited for winter since about March! lol



vp1.jpg vp2.jpg vp3.jpg
 
Yep. they're a solid piece of equipment. I just installed my first one up the road from you. Both I and the customer are looking forward to seeing what it'll do.
karl
 
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really.....where? Did you do the sheet metal work?
 
yeah, I was contemplating moving it closer. I plan on using pipe insulation on all the hot water lines too.
 
Not to hijack your thread, but does the Kuuma burn like my US Stove/Clayton? Do you just fill it full and it controls draft and temperature from the thermostat, or do you adjust your load size with the temperature you want in the house? That might sound a little confusing, but I was just wondering if the Kuuma is all manual like my current US Stove set up, or if can just load it and set temperature on the thermostat? Thanks
 
Not to hijack your thread, but does the Kuuma burn like my US Stove/Clayton? Do you just fill it full and it controls draft and temperature from the thermostat, or do you adjust your load size with the temperature you want in the house? That might sound a little confusing, but I was just wondering if the Kuuma is all manual like my current US Stove set up, or if can just load it and set temperature on the thermostat? Thanks



No, it's different than your US Stove. The Kuuma has a computer on it which allows you to control how much heat output you want, from low to high. It has, what looks to me like, a variable potentiometer; meaning you have more than just three settings to control how much heat you want from it. It's marked low, medium and high, but you are not limited to just those three settings. The computer uses a thermocouple to determine current heat output and automatically adjusts the damper (which is also controller by the computer) for whatever rate of burn you have it set at. The hotter you have it set the more air it allows in through the damper and the more heat you will get. The draft is auto regulated by using a barometric damper which is set at 0.06" W.C. There is a two speed fan, which is controlled by an included wall mounted thermostat. When the thermostat calls for heat, the blower system automatically kicks on high. When the temperature is satisfied and the thermostat "kicks off", the blower system switches back to low where it stays until the thermostat calls for heat again. All this means you can fill it full and not worry about adjusting anything but a little dial to control the heat output you want. The burn times are dependent on what heat output setting you have the computer set as well as how much wood you put in the firebox. More wood + low setting = longest burn times. It will still be possible to overheat the house during the shoulder seasons when it's not as cold, but you can help control that by the type & quantity of wood you use during the shoulder seasons. Anything that burns hot and quick would probably be your best bet to take the chill out on those somewhat warmer days.

 
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No, it's different than your US Stove. The Kuuma has a computer on it which allows you to control how much heat output you want, from low to high. It has, what looks to me like, a variable potentiometer; meaning you have more than just three settings to control how much heat you want from it. It's marked low, medium and high, but you are not limited to just those three settings. The computer uses a thermocouple to determine current heat output and automatically adjusts the damper (which is also controller by the computer) for whatever rate of burn you have it set at. The hotter you have it set the more air it allows in through the damper and the more heat you will get. The draft is auto regulated by using a barometric damper which is set at 0.06" W.C. There is a two speed fan, which is controlled by an included wall mounted thermostat. When the thermostat calls for heat, the blower system automatically kicks on high. When the temperature is satisfied and the thermostat "kicks off", the blower system switches back to low where it stays until the thermostat calls for heat again. All this means you can fill it full and not worry about adjusting anything but a little dial to control the heat output you want. The burn times are dependent on what heat output setting you have the computer set as well as how much wood you put in the firebox. More wood + low setting = longest burn times. It will still be possible to overheat the house during the shoulder seasons when it's not as cold, but you can help control that by the type & quantity of wood you use during the shoulder seasons. Anything that burns hot and quick would probably be your best bet to take the chill out on those somewhat warmer days.



Sounds like it's as close to an OWB as you can get, but still have the furnace in the house and burn just a fraction of the wood?? I'm also guessing it will burn less wood than the Clayton/US Stove?
 
No, it's different than your US Stove. The Kuuma has a computer on it which allows you to control how much heat output you want, from low to high. It has, what looks to me like, a variable potentiometer; meaning you have more than just three settings to control how much heat you want from it. It's marked low, medium and high, but you are not limited to just those three settings. The computer uses a thermocouple to determine current heat output and automatically adjusts the damper (which is also controller by the computer) for whatever rate of burn you have it set at. The hotter you have it set the more air it allows in through the damper and the more heat you will get. The draft is auto regulated by using a barometric damper which is set at 0.06" W.C. There is a two speed fan, which is controlled by an included wall mounted thermostat. When the thermostat calls for heat, the blower system automatically kicks on high. When the temperature is satisfied and the thermostat "kicks off", the blower system switches back to low where it stays until the thermostat calls for heat again. All this means you can fill it full and not worry about adjusting anything but a little dial to control the heat output you want. The burn times are dependent on what heat output setting you have the computer set as well as how much wood you put in the firebox. More wood + low setting = longest burn times. It will still be possible to overheat the house during the shoulder seasons when it's not as cold, but you can help control that by the type & quantity of wood you use during the shoulder seasons. Anything that burns hot and quick would probably be your best bet to take the chill out on those somewhat warmer days.



Very good description mr. Hawk. But the high limit will also turn hi speed on, not just the t-stat. Also just my opinion but use 45* fittings instead of 90's. Or better yet soft copper for a nice swoop. You want the least amount of (friction) that's not the right word but a am having a major brain fart right now. Resistance!!!! is the word ha. For the most of the thermo syphon flow.
 
Sounds like it's as close to an OWB as you can get, but still have the furnace in the house and burn just a fraction of the wood?? I'm also guessing it will burn less wood than the Clayton/US Stove?

I can't comment on the amount of wood, as I have yet to use mine and have only a fireplace to compare it to.....lol

Very good description mr. Hawk. But the high limit will also turn hi speed on, not just the t-stat. Also just my opinion but use 45* fittings instead of 90's. Or better yet soft copper for a nice swoop. You want the least amount of (friction) that's not the right word but a am having a major brain fart right now. Resistance!!!! is the word ha. For the most of the thermo syphon flow.

Dan, yeah, I'm planning on telling them 45° fittings, as I want to maintain a grade for the water to thermo cycle and to help eliminate any flat spots. I will mention soft copper to him and see what he says. True, I forgot about the high limit switch also turning the high speed fan on.

I also have an update. My dedicated main power was made live today after having an electrician verify my wiring (which was all correct BTW :) ). Flipped the main 110V switch and my Humidistat upstairs came to life (which it is was supposed to, as it's powered by the 24V R & C on the VF). I then flipped the dip switch on the VF100 (after temporarily connecting the high limit switch) and the VF's computer came to life and gave the correct read-out (damper closed cold). Gettin' closer! :cool:
 
really.....where? Did you do the sheet metal work?
Near Manawa. We're out of Stevens Point, and Manawa is about halfway between us and Appleton. I did all the installation with the exception of the bonnet which a local shop built for us. also put an electric boiler with a hot water coil in the plenum for backup. I do 95% boiler and solar hot water work so duct and forced air is not my stong point, but when push comes to shove, I can get it done. The last month we've put in a GARN Jr. a Kuuma, and a Windhager. Been busy.
 
Although I have no experience with the VF, I think I would also try to raise the hot water tank as high as possible too, for better convection. Maximize the vertical rise coming out of the VF, and minimize the horizontal. And biggest practical diameter pipe.

Sounds like it's as close to an OWB as you can get, but still have the furnace in the house and burn just a fraction of the wood??

Not sure I'm understanding - in what ways would it be close to an OWB?
 
Although I have no experience with the VF, I think I would also try to raise the hot water tank as high as possible too, for better convection. Maximize the vertical rise coming out of the VF, and minimize the horizontal. And biggest practical diameter pipe.

Sounds like it's as close to an OWB as you can get, but still have the furnace in the house and burn just a fraction of the wood??

Not sure I'm understanding - in what ways would it be close to an OWB?

I was comparing the 2 by the having the ability to just fill the firebox full of wood, set the thermostat where you want it, and not worry about it anymore, until you're out of wood. I didn't know if the Kuuma worked this way or if it had all of the manual adjustments that my US Stove/Clayton does.
 
Although I have no experience with the VF, I think I would also try to raise the hot water tank as high as possible too, for better convection. Maximize the vertical rise coming out of the VF, and minimize the horizontal. And biggest practical diameter pipe.

But don't you still want the lower cold water supply on the tempering tank to be below (or at least equal to) the bottom intake tube on the water coil in order to facilitate proper water flow? The coldest water should be at the bottom of the tempering tank and as you move out of the tank into the water coil the water will be getting warmer and warmer which will help thermocycle the water. If the water coil supply is actually higher than the low nipple on the tempering tank I would think it would then hinder the thermocycling.

I can raise the tank ~4" or so more, this would place the bottom nipple on the tank at approximately the same height as the bottom nipple on the water coil.
 
But don't you still want the lower cold water supply on the tempering tank to be below (or at least equal to) the bottom intake tube on the water coil in order to facilitate proper water flow? The coldest water should be at the bottom of the tempering tank and as you move out of the tank into the water coil the water will be getting warmer and warmer which will help thermocycle the water. If the water coil supply is actually higher than the low nipple on the tempering tank I would think it would then hinder the thermocycling.

I can raise the tank ~4" or so more, this would place the bottom nipple on the tank at approximately the same height as the bottom nipple on the water coil.

JR, why are you entering at the element heights? Why not cold from the drain, hot to the relief valve spot. Your other hot water tank relief will work for both tanks as the are/will be the same pressure.
 
JR, why are you entering at the element heights? Why not cold from the drain, hot to the relief valve spot. Your other hot water tank relief will work for both tanks as the are/will be the same pressure.

hmmm, I guess I never thought of doing things that way. ;em That would definitely make more sense now wouldn't it. Although, in the dead of winter I was hoping to isolate the tempering tank with valves to shut down my LP water heater all together just to see if just the VF heated water will be enough for us. With the limited amount of water we go through I'm guessing a decent amount of LP is used just to keep the water inside the LP water heater up to temp and doing this will cut down on our LP useage even more. Although, I don't know how hot the water will get inside the tempering tank and if it will even get hot enough to do this or if it will get too hot to where it's a danger to not have a blow off valve when the LP water heater is valved closed and therefore not seeing the same pressure.

comments?

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Just talked to the guy who will be doing it. We will be using the drain and relief spots as you mentioned. He will also be teeing in a place for the relief valve so I can use the tempering tank like I mentioned above. I wouldn't want to isolate the tempering tank if there was no relief valve. I don't need it turning into a missle!
 
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Sounds like it's as close to an OWB as you can get, but still have the furnace in the house and burn just a fraction of the wood??
It would be more accurate to say the opposite, that the VP is about as far from an OWB as you can get. The VP's combustion design, heat exchanger design, and computerized burn control, along with the quality of its manufacture, puts the VP at the top of the field of hot air wood furnaces. And the very low emissions and high efficiency testing results probably put the VP nearly into a class by itself.
 
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hmmm, I guess I never thought of doing things that way. ;em That would definitely make more sense now wouldn't it. Although, in the dead of winter I was hoping to isolate the tempering tank with valves to shut down my LP water heater all together just to see if just the VF heated water will be enough for us. With the limited amount of water we go through I'm guessing a decent amount of LP is used just to keep the water inside the LP water heater up to temp and doing this will cut down on our LP useage even more. Although, I don't know how hot the water will get inside the tempering tank and if it will even get hot enough to do this or if it will get too hot to where it's a danger to not have a blow off valve when the LP water heater is valved closed and therefore not seeing the same pressure.

comments?

<edit>
Just talked to the guy who will be doing it. We will be using the drain and relief spots as you mentioned. He will also be teeing in a place for the relief valve so I can use the tempering tank like I mentioned above. I wouldn't want to isolate the tempering tank if there was no relief valve. I don't need it turning into a missle!


One additional comment from here would be not to do anything to the tank that would prevent re-installing the elements in the future. Or maybe go even further, and just install them now while it's empty. There is not much that is more efficient for home DHW heating than a conventional (well insulated) electric hot water heater - if it ever came to the point that the only reason you have LP at the house is for DHW heating (not knowing what else you use it for), it would be very easy to send the LP tank down the road & hook some juice up to your tempering tank as it would be all ready for it.

My sidearm/FPHX heating loop is tied in to my relief port on top (tied into the bottom feed entry at the bottom) - I just unscrewed the relief valve, screwed a T in there, then screwed the relief valve into one side of the T while the other side is my heating loop. Use lots of ball valves to isolate everything, including one on the loop side of that T - but make sure you leave enough room between the T & the valve (like with a 2 or 3 inch nipple) so the valve won't pinch or bring up on the stem of the relief valve when you go to close it. Learned that one the hard way.
 
I was comparing the 2 by the having the ability to just fill the firebox full of wood, set the thermostat where you want it, and not worry about it anymore, until you're out of wood. I didn't know if the Kuuma worked this way or if it had all of the manual adjustments that my US Stove/Clayton does.

I think most any wood burning central heating unit operates the same way once the fire is going - fill it up & let it go until it needs wood, or you need more heat, again. But comparing the Kuuma to an OWB is kind of doing a big disservice to the Kuuma. The OWB 'accomplishes' that in a very clumsy way with lots of downsides - it just closes the air off & smolders the wood. I think the Kuuma neither works that way, nor has manual adjustments your US Stove does.

If any appliance that heats water with wood is being touted, or considered for purchase, on the basis of long burn times - beware.

All that said assuming you were referring to long unattended burns - if the 'long' part is taken out of that assumption, that's likely worse, as that would mean lots of refilling & tending and a huge supply of wood.
 
Sorry - one more comment on the tank. Along with maybe getting it higher, try to get some insulation under it too. Mine is up on a wood stand, with 1.5" of foam board under it (maybe should have had even more), and a layer of fiberglass wrapped around it & on top. Very little stand by heat loss.

And plumb in heat traps at the top of the tank.

And I guess one more - see if you can find some 'real' fiberglass based pipe insulation. Like Knauf. That stuff makes a big difference especially in a convection/recirculation based heating setup. Keeps all the heat where it's supposed to be. I found it here at a drywall place. But if you can't find it, two layers of the black stuff isn't bad either. 1.5" stuff almost goes right over the 3/4" stuff like it was made to.
 
Sorry - one more comment on the tank. Along with maybe getting it higher, try to get some insulation under it too. Mine is up on a wood stand, with 1.5" of foam board under it (maybe should have had even more), and a layer of fiberglass wrapped around it & on top. Very little stand by heat loss.

And plumb in heat traps at the top of the tank.

And I guess one more - see if you can find some 'real' fiberglass based pipe insulation. Like Knauf. That stuff makes a big difference especially in a convection/recirculation based heating setup. Keeps all the heat where it's supposed to be. I found it here at a drywall place. But if you can't find it, two layers of the black stuff isn't bad either. 1.5" stuff almost goes right over the 3/4" stuff like it was made to.


thanks for all the info!

I thought about setting it on some foam board, but then I questioned the integrity of the foam with all the weight on it. I didn't want the foam failing and have the water heater tip to one side.

As far as getting it higher....can the drain on the tempering tank (cold supply) be higher than the lower "cold" intake on the water coil? One would think you'd want the lower connection on the water coil to be at least at the same level or higher than the cold water supply coming from the tempering tank. Does this matter?

I also heard some not so good things about those heat trap nipples, so I decided against them. Unless you are referring to something different...?

As far as valves go, I think I have a total of 7 of them. I have it valved it such a way where I can isolate the coil, tempering tank or water heater.
 
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My tank is 80 gallons, and has been sitting on a piece of 1.5" cheap foam board for almost 2 years now. No issues seen. I did run a piece of strap around it & fastened it to the underneath of a stairwell right behind it - just in case something weird happened. Don't think there's issues with weight on foam board though.

Heat trap - just a short section in your pipe that goes down & back up again (8"+ or so) right after the tank exit. Principle is that heat won't leak out of your tank & make it past the down part.

I don't think it matters about the tank inlet (which actually is an outlet in the convection flow) being higher - but again I'm not familair at all with a Kuuma. The more you can vertically separate the generating part (Kuuma) from the absorbing part (tempering tank) of the convection system, and keeping it as direct as possible, the more flow will be generated. Straight up & down is optimum - try to get as close to that as possible. My heating zones will heat by convection - the upstairs ones a lot better than the downstairs ones although one of the downstairs ones has next to no horizontal separation. So giving it as much 'up' as practical will get more flow going.
 
valves are a must. You most likely will not be able to shut down the lp heater., The Kuuma is a helper coil not a heating coil. keep in mind if your tank was 120* and you took a 10 min shower at 3 gal a minute, you just mixed 30 gal of 50* water into the 50gal you have left. It takes a long time to heat an 80 gal tank via thermo syphon. Get a hp water heater tied in to that system and you can get the savings your looking for.
 
Here are some in-progress photos of my Vapor Fire 100. I have 98% of the wiring done and just waiting for the HVAC guy to make/install the plenum and duct it over to the existing ductwork so I can wire in the powered damper and high temp limit switch. I found a used 40 gallon electric water heater which I cleaned out, removed the heating coils, installed new fittings/anode rod/pop-off & drain valves and have it ready to be connected to the water coil on the Kuuma. Also have everything wired and set for the humidifier I'll be installing on the plenum. Daryl has been a tremendous help and the build quality of the furnace is amazing. This coming winter and all future winters will be completely different than what we are used to.....which was burning 4+ cords of wood while still using ~$2,000 worth of propane a year all while keeping it 50°-52° at night & when at work. Then having to build a fire in the fireplace after getting home from work to "heat" the house while we were home. Repeat every day throughout the winter. It sounds a bit crazy, but I've been excited for winter since about March! lol


View attachment 135531 View attachment 135532 View attachment 135533
Nothing crazy about longing for wood heat
 
OK, I re-did the fittings and raised it up about 14".

I put a tee on the top so I can still use the tp valve and one on the bottom so I can have a drain. I don't have everything tightened, I just placed them there and I may let the guy dope them and tighten them to the position he wants them in while sweating the pipes. I installed the original heating elements, solely for plugging purposes.

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