I have a stove that can burn green pine and not get creosoted! Check it out!!
- Thread starter mlbeardsley
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
- Status
Karl_northwind
Minister of Fire
what's wrong with a 125+ degree delta T on a boiler/water heater?
sounds like solid engineering to me
K
maple1
Minister of Fire
I can only imagine the velocity of water that would be required to move a half million btu's through 1" pipe. I think I also read on that site that all of their boilers hold "10-15 gallons" of water. If I was really bored I'd love to briefly review the thermodynamics involved in transfering that much heat into into such a small amount of water.
AHAAA...eureka moment....with a velocity exceeding 32fps or even higher(maybe with anything over 50fps we make hot seltzer as well) the heat will get there faster....faster, better...
500kbtu into 1" at a 10 gallon capacity?? flowing into how many districts? one u say?
(broken link removed)
Interesting. wondering ..is this thing reviewed by any engineering/approval agencies?
Scott
Karl_northwind
Minister of Fire
just in case it didn't come across, that's sarcastic....what's wrong with a 125+ degree delta T on a boiler/water heater?
sounds like solid engineering to me
K
Masonry principle regarding heaters, no problem there, but boiler-wise engineering...not sure there.
Masonry mass absorption can be a detriment to the operation of the system in boiler principle design..heat should be delivered to district system and not absorbed by unit.
Scott
Agreed, but I thought this was an outdoor unit...so you are talking massive insulation.
I happen to like the masonry idea..but not outdoors.
I still do not see 1/2 million btu vs 1" outlet and limited capacity, as favorable..especially when the mass needs to be maintained.
On the flue comments again I concur and why not do a Finnish style masonry design with dual downturns to increase efficiency and absorption.
Scott
I happen to like the masonry idea..but not outdoors.
I still do not see 1/2 million btu vs 1" outlet and limited capacity, as favorable..especially when the mass needs to be maintained.
On the flue comments again I concur and why not do a Finnish style masonry design with dual downturns to increase efficiency and absorption.
Scott
This is true. Masonry/Stone/Soapstone heaters are nothing new and work well if done right using the stone or cement itself as the heat emitter. I have always questioned though, the efficiency of using the heated mass to heat water as a secondary output. Why not just heat the water directly via a good heat exchanger design?........"good heat exchanger design" being the key phrase here.
My unit has a baffled system in the cement so it has to travel through a few times. I think thats what makes these efficient plus they are insulated all the way around.
Thanks for this link. I don't know why, but I didn't see any links or pics of what this thread was about until you posted.
I welcome the discussion of this new-to-me gasser.
I trust the moderator to keep the sales pitch to a medium level, and let us chime in with our thoughts and experiences.
If the burning wood is drying out the green wood above it, the moisture is still making its way up the chimney.
You can't avoid the creosote, as far as I can see.
(There is no breakdown of the H2O in the 2000F gassification chamber, is there?)
I know burning green wood loses efficiency but that's what i have a times. The reason I like mine is that I can only get green wood for free and it doesn't get creosote all over. I think it happens because the walls being masonry let the firebox get that much hotter. When their is no flacky creosote on the wall the radiant heat can transfer better. There gasiers can burn a little wet wood they said but not alot. The primary chamber he said just isn't effected by the creosote. Also I think they are wrong about their system only holding 10-15 gals because mine has a 55 gallon storage tank.
RE: green wood.
We've gone over this a few times here but it's worth refreshing some memory's.
Simply put, in order for the fuel (wood) to burn, the water/moisture has to be evaporated out of it first. Evaporating that moisture from the fuel takes a significant amount of heat, on the order of about 1000btu's per pound at the point of phase change from liquid to vapor. Looking at just that aspect of the burning process, you can quickly calculate that wood having a 45% moisture content will "steal" 45,000 btu's of heat / hundred pounds of fuel, just to effect the change from liquid entrapped in the wood itself to vapor which can escape. One could say that using wood seasoned to around 20% automatically increases the system efficiency by 25% compared to the moisture content mentioned before. When you add the heat required to bring that moisture up from ambient temperature to the phase change point (212*F) the difference is even more pronounced.
This is a tremendous loss of efficiency and waste of fuel. I don't care if it's "free" or not. It's still a poor use of the resource and causes a much dirtier burn than one would see using seasoned wood.
I really have a problem with anyone bragging or advertising that their unit will burn "green wood". Claims like that are what got us to the point of EPA involvement in the first place and to see that poor practice "encouraged" just perpetuates the black eye the entire industry has sustained. We all as wood burning consumers, dealers, manufacturers and reps need to adopt a best practice attitude and actively discourage poor use of the resource or some day that option will be taken from us. Don't believe for a minute that elimination of wood burners entirely has not been discussed.
Don't brag on being able to burn green wood!!
PS: to answer your second question regarding H2O breaking down. No it does not. Temperatures required to do that are more toward the "nuclear" end of the scale. (hyperbole intended)
30years ago I built what was called a HASSA from mother news plans. It was a simular type using sand with heat exchangers pipe running thru it. Great consept but it had some problems. The way they can get by with I in outlets is they are using the concrete as storage and only pulling off heat with the water. So you can only get say 80000btu's per hour to your house but can fire at 500000 in a burn. The problem is if you fire continueously at 500000. once the concrete gets to boiling temp you can't pull the btu's off fast enough and things will get very interesting. The HASSA used a copper and pvc pipes. 3/4 in pvc can swell to over 6in and gets very thin if you over fire and get the sand (or concrete) over 240* at 25psi. Copper pipes can and will become unsoddered if the sand or what ever gets to high from putting in to many btu's. Been there done that. 3/4 pipe just won't move enough btu's for my house so I had to fire it on the edge and had baseboard also so needed 180*+. Heated the place for two years before it destroyed it self. Rebuilt it, ran with all copper, outside shell busted apart from thermo expansion and contraction , sand ran out letting chimney sag and tried to burn the shed down. Gave up...........
If I remember in the instruction it said. Build small fires and don't over fire. guess I missed that.
The point I'm trying to make is it may put out 500000btu's but with out proper piping size and pumps and distrubution you better have a place for those btu's. I do think they will burn cleaner than typical OWB's but you won't have the efficency as a commercial engineered gasser.
leaddog
If I remember in the instruction it said. Build small fires and don't over fire. guess I missed that.
The point I'm trying to make is it may put out 500000btu's but with out proper piping size and pumps and distrubution you better have a place for those btu's. I do think they will burn cleaner than typical OWB's but you won't have the efficency as a commercial engineered gasser.
leaddog
It would be interesting to be around to hear the noises that would come from that unit firing at 500,000 btu if the circulator should fail although I probably wouldn't want to be that close.
This is one of those things that one would assume to be self-evident, given that masonry is more dense than water, but it is incorrect by a large margin.
You have to go by the "specific heat" of the material, and water's specific heat is dramatically more than masonry (about a 5:1 ratio). Don't believe me? Ask the masonry industry:
(broken link removed to http://www.cmacn.org/energy/basics/mat_sh.htm)
I'm not trying to be snippy, but it _is_ essential to tie discussions and advocacy back to physics, not supposition.
Water's physical characteristics, specifically in regard to heat retention and heat-transfer, would be considered truly extraordinary in comparison to nearly all other materials (except for really exotic phase change materials), except we're all so used to having the stuff fall out of the sky that we don't stop to realize that it has these unique properties.
This whole thread still baffles me a bit.
M Beardsley, you clearly must be the same Marsha Beardsley who left a rave review on the Heiss website, correct? And it just so happens the person two or three "testomonials" above you on the website is the owner of Heiss Heaters according to a quick lookup of the LLC registration. Are you being compensated somehow for your efforts to evangalize the hearth.com masses as to the greatness of Heiss?
I hate to say it but anyone that comes to this site or any other wood burning site and claims that the material used to construct a boiler can somehow magically enable it to burn green wood creosote-free is just plain old misinformed. And it comes off as rubish when we read it. Furthermore, how many OWB operators really care about creosote? Most OWB owners I know expect a chimney fire once or twice a year - it cleans the pipe out quite nicely according to them.
If you want to bring some data that might back-up the performance claims of Heiss we'd absoltuely love to see it and discuss it. But I think anyone on this site would suggest that Heiss Heaters stop pushing the creosote marketing angle and the "steel boiler bashing" if they ever want to be taken seriously by a knowledgeable group of wood burners.
M Beardsley, you clearly must be the same Marsha Beardsley who left a rave review on the Heiss website, correct? And it just so happens the person two or three "testomonials" above you on the website is the owner of Heiss Heaters according to a quick lookup of the LLC registration. Are you being compensated somehow for your efforts to evangalize the hearth.com masses as to the greatness of Heiss?
I hate to say it but anyone that comes to this site or any other wood burning site and claims that the material used to construct a boiler can somehow magically enable it to burn green wood creosote-free is just plain old misinformed. And it comes off as rubish when we read it. Furthermore, how many OWB operators really care about creosote? Most OWB owners I know expect a chimney fire once or twice a year - it cleans the pipe out quite nicely according to them.
If you want to bring some data that might back-up the performance claims of Heiss we'd absoltuely love to see it and discuss it. But I think anyone on this site would suggest that Heiss Heaters stop pushing the creosote marketing angle and the "steel boiler bashing" if they ever want to be taken seriously by a knowledgeable group of wood burners.
Karl_northwind
Minister of Fire
the thing that makes masonry heaters work is that the inner bits get to a couple thousand degrees during and after a burn, unfortunately with water we're limited by the working delta T, that being the difference between the minimum useable temp and the boiling point. masonry for all it's good and bad points, doesn't have a phase change, (at least that we're going to reach in this situation)
there are some electric off peak storage units that heat (tons of) firebrick up to 2000F and store the heat there for later use.
water is just about the best, in that it holds a lot of heat, is easy to move around, is cheap, only mildly corrosive, and works in the ranges we want to work in. as long as you can keep it from boiling and or freezing, good to go.
Just so I am clear, I think that masonry heaters are an amazing technology- relatively low tech to build, relatively simple to run, quite efficient, and need no pumps, electricity, or complex controls- I just don't see that they necessarily make a revolutionarily different boiler (or even an optimal boiler).
Exactly. If you're going to use water as the heat transfer medium, why not just heat it directly and install enough storage for the parameters of the job?
At risk of playing devil's advocate against myself, I _can_ envision situations in which a hybrid masonry heater/ boiler might make sense- such as when the masonry heater part of the unit is located in a rather large relatively open space/ spaces (so that it can spread its heat easily and directly by unrestricted radiation and convection) but you also want to be able to send heat to a different area that would not be effectively warmed directly by the masonry heater. Seems like you lose the stone-simple near-failproof characteristics of the masonry heater in the process though, without fully gaining the ability that a high efficiency boiler + well insulated water storage yields of bring able to efficiently"bank" large quantities of heat for release only when or at the rate that is desired. Different strokes for different folks.
Water has a specific heat of 1 (one). You'd think you can't go lower than that, BUT, all other materials with the exception of phase change materials, ie, eutectic salts are lower in specific heat than water.
Water is truly a unique material. It expands when it's heated and it expands when it freezes. And it can be turned in to ice cubes to cool my scotch. We're lucky to have it!
- Status
Similar threads
