JUCA Non-Airtight Insert

[laynes69]

I was wondering if anyone has ever heard of these here? Heres the debate....http://arboristsite.com/showthread.php?t=38965
Was wondering some thoughts about this. Im not trying to open worms here, but to get some input on these.

 

[[email protected]]

HA!

 

[Corie]

I looked over their website, and while the heat transfer science they use isn't anything that spectacular it is correct.

However, I still have a hard time seeing where the clean burning comes from? Heat transfer efficiency is great, but where does the emissions reduction join the equation?

 

[Mike Wilson]

Don't waste your time. My understanding is that they are no longer in production. Notwithstanding that, the whole concept appears specious, at best.

-- Mike

 

[laynes69]

Its an open fireplace with glass doors and tubes going through it, or so thats how it seems. I dunno.

 

[stoveguy2esw]

i couldnt make sense of it , the fact that they are reducing chimney temps and still not having creosote, and especially moisture related issues is beyond me. the part about burning large logs was interesting , they didnt list burn times specifically that i saw. how long is "long" and what is actually happening in the flue with the "lower chimney temps" water vapor (steam) changes to liquid at 211 degrees F if the start temp coming out of the top of the stove (im assuming that is where they are reading temp) is below 300F how is the vapor staying above transitional temperature all the way out the top? burning green wood? i dont care how hot the fire is, the wood has to dry out and create steam as it does before pyrolisis occurs. and this is going to put large amounts of moisture in the flue which will cool the flue, this is not even taking into account the water which is a natural byproduct of pyrolisis. the only answer i can think of is that the air budget must be massive. i do see as well that the epa certification was deftly sidestepped stating that the unit does not fall into the criteria that requires an epa certification , this means it is epa exempt or 35/1 air fuel that in itself is going to drasticly cut down on where the unit is legal to operate. as for efficiency , i'd like to know what it would rate at. and what kind of PM reading it would regester at , not bashing , just real dang curious.

 

[[email protected]]

If you navigate around that site you will see that they also have a way to stop Hurricanes form happening. No kidding.
http://mb-soft.com/public/hurrican.html

 

[stoveguy2esw]

geez,
did al gore write that stuff ??????

 

[Mike Wilson]

If you navigate around that site you will see that they also have a way to stop Hurricanes form happening. No kidding.
http://mb-soft.com/public/hurrican.html

I think its time that they put the bong down....

 

[stoveguy2esw]

i dunno about you , but i wanna see sombody fly at mach 1.1 within 50 miles of a hurricane and try to bank the aircraft. there is no way that would fly , for starters there likely is not a supersonic plane fitting that description that has a big enough seat to hold the cojones of any pilot who would even think of flying that sortie

 

[stoveguy2esw]

i dunno about you , but i wanna see sombody fly at mach 1.1 within 50 miles of a hurricane and try to bank the aircraft. there is no way that would fly

 

[laynes69]

Well thought it was just me. Guess not. I think there are 130 something pages on that site about these things. Brainwashing People.

 

[stoveguy2esw]

i dunno laynes, i have been in the stove manufacturing buisness since 1993 and ive never heard of this brand before today. i think i would have to have some clearer answers as to why they have to limit production, not advertise, and even more important , i wanna know who did the safety testing on the unit. even if it does not have to be tested to meet epa standards , it still has to be safety tested to meet ul standards before it can be installed inside of a residence. im afraid i would have to stay clear of this brand unless they could provide me with this information.

aside from that , i have had a few laughs at the spinoffs from your post , and i hope you didnt take offence from them. but what i said above in this post is how i would look at it were it me.

 

[laynes69]

I have wondered the same thing everyone else has about these. I think these things are a joke, and your right who or are they tested by? The man that has this one thats posted says he will use 3 cords this year to heat his home bragging he burns 1 x 2' green logs in this thing. I was just wondering what others thought of this super insert. Also a 12 cubic foot firebox........I'll just keep it at that.

 

[stoveguy2esw]

well, 3 cords is 3 cords , may be a good bit less than some use in here , more than i ever have, but the variables in that are quite wide, im my home i have 2 of our stoves ( i work for englander) i have a 24-ac catalytic woodstove , and i have a 25-pdvc pellet unit. never have i run both at the same time , no need i have a 1250 sq ft ranch , live in south central Va and im pretty well insulated. now if i lived in montana and had a 2500 sq ft home and was not as well insulated , 3 cords would be a steal for me. so the variation between locations alone is quite a bit. i burned (when i just had the woodstove , about 3 ford ranger pickup truck loads in a season ,if that. now that im using the pellet unit mostly (wife likes the simplicity) i burn about 1.5 ton of pellets on average per season. i have customers who burn 4 to 5 tons in a year up north. like i said there are a lot of variables.

i cannot say " the thing is a deathtrap" on the contrary , it may very well be fully listed and a very solid unit , i just do not know of it personally and before i would back off my stance i would need to know more specifics. if sombody shows these things to me , i will retract my statement live and in color right here in this forum. i have been corrected in the past and have been happy with the knowledge i gained from the correction. but i would like to know about the answers to the concerns i have about this brand. and i will stand with my opinion until i am(not proven wrong) but educated. my biggest concern isnt that another company is showing up my product (hey there are a lot of great manufaturers out there who by the way do not dance around like this one does)my biggest concern is safety, plain and simple. my posts are my way of showing that i have your best interests at heart

 

[DiscoInferno]

My parents have a unit that looks suspiciously like some of the pictures on the JUCA site; a glass-enclosed fireplace with a huge black steel pyramid (heat exchanger) above and a big blower below in the crawlspace. It's in their (mostly summer) vacation house (built around 1977) and thus has had limited use; the blower went out years ago and has not been replaced, and I don't think it can run without the blower. I do recall that it easily heated the whole house, but I have no idea how much wood it used or how much gunk is in the heat exchanger or chimney. My guess is that it has never been cleaned. They've asked about replacing the blower, if I do that I'll get the chimney cleaned also.

 

[mtarbert]

I looked over the web site last evening...some of it.Some of their equations are mis applied (at best) .The units seem inexspensive enough to give on a try .I would like to see one in use.

 

[_CY_]

just now found this thread discussing my custom JUCA insert at Aboristsite... Yes I love chainsaws!

yes it's real and very well constructed out of 1/4in steel.
yes it's got a 12 cubic feet firebox..
yes it uses a ton of air which is feed via ash dump. no inside air is used for combustion.
yes key to it's efficiency is it's super high heat transfer abilities. it's one big hollow heat exchanger with a high volume blower... controlled by a thermal fan switch. all electrical components are UL rated.

the plan is to add a secondary burn system. which should double it's burn efficiency.
no.. it doesn't creosote... 3 season with almost no creosote in chimney. high temps generated results in a complete burn, means no creosote.

no I don't burn green logs all the time. example was posted to showcase JUCA's clean burn ability. when I first started burning wood... didn't have time yet to cut and season wood. when one runs out of wood... and all you have on hand is green wood. one finds the best green wood available which is ash. that and dead standing oaks.

in Tulsa, OK... my home is a well insulated 2500 sqft single level ranch style home built mid 50's. My JUCA has been the only source of heat for 3 seasons. last season burnt a little over 4 cords of hardwood. a mixture of Oak and Pecan.

yes.. there's some wacky topics on the JUCA site... but it also happens to contain the most information of wood burning on the WWW. where else would one find out which wood burns the best green. or how to properly duct your heat output into your existing HVAC. there's diagrams on how to construct flappers to handle air flow direction. etc..etc..etc.

yes.. JUCA wall angles are very carefully designed to draft. when doors are closed, the fire noticeably increases in intensity.

have no idea about JUCA production status... one thing is for sure... JUCA could care less about selling you one or not...

ordered all the options possible for my insert. which by the way, was custom built to fit my fireplace. based upon the dimensions I sent in. since I have a large fireplace... I ended up with a large insert... with a 12 cubic feet firebox. fit was perfect with close tolerances from insert to fireplace interior, including interior angles. Custom all the way!

received a world class product at a super reasonable price... paid a total of $1,850 including shipping to Tulsa dock. don't know of any mfg that could even come close to what I received for $$ spent.

well, 3 cords is 3 cords , may be a good bit less than some use in here , more than i ever have, but the variables in that are quite wide, im my home i have 2 of our stoves ( i work for englander) i have a 24-ac catalytic woodstove , and i have a 25-pdvc pellet unit. never have i run both at the same time , no need i have a 1250 sq ft ranch , live in south central Va and im pretty well insulated. now if i lived in montana and had a 2500 sq ft home and was not as well insulated , 3 cords would be a steal for me. so the variation between locations alone is quite a bit. i burned (when i just had the woodstove , about 3 ford ranger pickup truck loads in a season ,if that. now that im using the pellet unit mostly (wife likes the simplicity) i burn about 1.5 ton of pellets on average per season. i have customers who burn 4 to 5 tons in a year up north. like i said there are a lot of variables.

i cannot say " the thing is a deathtrap" on the contrary , it may very well be fully listed and a very solid unit , i just do not know of it personally and before i would back off my stance i would need to know more specifics. if sombody shows these things to me , i will retract my statement live and in color right here in this forum. i have been corrected in the past and have been happy with the knowledge i gained from the correction. but i would like to know about the answers to the concerns i have about this brand. and i will stand with my opinion until i am(not proven wrong) but educated. my biggest concern isnt that another company is showing up my product (hey there are a lot of great manufaturers out there who by the way do not dance around like this one does)my biggest concern is safety, plain and simple. my posts are my way of showing that i have your best interests at heart

 

[DiscoInferno]

the plan is to add a secondary burn system. which should double it's burn efficiency.
no.. it doesn't creosote... 3 season with almost no creosote in chimney. high temps generated results in a complete burn, means no creosote.

If there is room to double the burn efficiency then complete combustion obviously isn't taking place despite copious amounts of combustion air. Certainly in my parents' unit the firebox is huge and uninsulated, and there is seemingly no way it could get hot enough outside the immediate flame area for complete combustion. The incomplete combustion products have to go somewhere; if not deposited as creosote in the chimney, then the only remaining option seems to be that it sends them out as smoke. That's also how my Majestic fireplace works, for example; it has tons of excess air and leaves absolutely no creosote, but the firebox design doesn't allow complete combustion. So stuff is coming out of the chimney. It even generates a decent amount of heat, and would do better with a better heat exchanger, but efficiency-wise it's no match for my EPA Ultima.

 

[_CY_]

good point... my figure of doubling efficiency is probably wrong...

currently my JUCA is using an open burn system, meaning it's operating similar to a conventional fireplace. firebox air is not dampened, huge amounts of air is used from outside via original ash duct.

the art of fireplace construction has been around for centuries. it's not unusual to find fireplaces that have burned for decades without cleaning. meaning that particular fireplace burned hot enough to not creosote. there's also poorly constructed fireplaces that require cleaning every season.

proof is output of chimney.... do you see bellowing smoke ... or barely a wisp...
after wood burner gets up to temps ... if it's burning cleanly, exhaust should be almost clear

if/when switch is made to secondary burn... fresh air entry point will routed to top of burn chamber vs coming from bottom currently. then entire firebox will need to sealed to control air. in other words switching to a conventional secondary burn system that dampens air intake to control rate of burn.

currently rate of burn is controlled by size/species of wood used. JUCA already has small sliding doors to control air intake. all I have to do is seal edges to make airtight. but if I do that without installing a secondary burn system. it'll then become a smoke/creosote making wood burner.

note comments are only valid for my JUCA insert. I've never seen another JUCA in person.

these two pic's show JUCA in action. both pictures were taken at same time. (can't seem to get pic's to post)

http://arboristsite.com/showpost.php?s=70d6169cdd97b10a34a1a2fa78dd3f48&p=510576&postcount=1

the plan is to add a secondary burn system. which should double it's burn efficiency.
no.. it doesn't creosote... 3 season with almost no creosote in chimney. high temps generated results in a complete burn, means no creosote.

If there is room to double the burn efficiency then complete combustion obviously isn't taking place despite copious amounts of combustion air. Certainly in my parents' unit the firebox is huge and uninsulated, and there is seemingly no way it could get hot enough outside the immediate flame area for complete combustion. The incomplete combustion products have to go somewhere; if not deposited as creosote in the chimney, then the only remaining option seems to be that it sends them out as smoke. That's also how my Majestic fireplace works, for example; it has tons of excess air and leaves absolutely no creosote, but the firebox design doesn't allow complete combustion. So stuff is coming out of the chimney. It even generates a decent amount of heat, and would do better with a better heat exchanger, but efficiency-wise it's no match for my EPA Ultima.