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greenhouse with a rocket mass heater vid  RSS feed

 
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no. the reason you are not getting (as you say) a straight answer is you are not asking a comprehensible question.  As suggested read the book so we can actually have some chance answering a question that relevant to the stove .
 
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Ernie wrote:
no. the reason you are not getting (as you say) a straight answer is you are not asking a comprehensible question.  As suggested read the book so we can actually have some chance answering a question that relevant to the stove .



I have removed any questions from the posts, so they won't be confusing to you.

To people in general:
I was interested in the rocket heaters, but have changed my mind as they do not look sufficient.

Most all of the people on the RH videos are all bundled up, even sitting there watching the heater.
I find that quite strange, as I could not sit close to my fireplace insert when all bundled up!

See the thing is I was thinking of removing the fireplace insert and building a RH in it's place.
But I'm getting more heat now from the insert then I would from a RH, from the same amount of wood used. 
I use about 1/2 a cord of wood each winter, to heat a 1400 sf house, and it is not cold inside.
There is no time that I need to bundle up when sitting right in front of the fire.

Really I do think a RH could be good, and could be useful, if it really put out more heat, for a similar supply of wood.  Apparently it does not.  The masonry mass heaters do, but they take much more planning and work to construct. 

I also get a strong feeling from some of the replies on here that the intent of these things is to sell books and seminars.  I certainly hope that's not the case.  But no answers, no results, don't seem to know how it works etc etc.  The results should be right there, the explanations easy to see, but they aren't.
 
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Miscommunication is an easy state to fall into for us all . . .

To help your understand John I would add that the RM stove is not designed to emit most of it's heat, as a fireplace/insert/wood stove are, right out the front.  It is designed to burn the off gasses more efficiently thereby recovering heat that would otherwise be lost straight up through the chimney. 

The RM stove is designed to store it's heat in mass for longer, even distribution over time, and not just provide a big heatwave during the burn.  So no, you won't get as much up front heat right in front of the unit as you do with fireplaces/inserts/wood stoves - however the mass of the RM stove will radiate heat long after the fire is finished, and the burn is very efficient because it's burning the gasses in addition to the wood.

Personally I like the Rumford Mass Fireplace/Stoves myself, but as you say they come with their own issues too.  So there are always trade offs, but in the case of heating a greenhouse the RM stove would be the best choice of the three designs hands down - due to it's long, steady heat distribution. 

The book isn't expensive and it is helpful, but you can wrap your brain around how this all works for free by doing research on the internet.

I hope this helps 

 
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johnlvs2run wrote:

But I'm getting more heat now from the insert then I would from a RH, from the same amount of wood used. 



How horribly frustrating.  For me.

I think the rocket mass heater is gonna kick butt on any insert.  You are saying that you are convinced that it won't because you saw a picture of somebody bundled up with one? 

As for selling books, I'm looking at your questions and I'm thinking "man, I don't wanna take the time to answer this, this guy is so far off the mark and is so dead set against understanding, this is gonna take six hours of my life and the guy still isn't gonna get it." - So, yeah, the book is crazy cheap and does an excellent job of conveying the message and none of us get royalties for it. 

So, you made your stand - you think what you have is gonna be superior.  Good for you. 

I am now going to make my stand:  I think a rocket mass heater will heat your home to just as comfy with five to ten times less wood.

Here's a thought:  check the book out from the library.  After you have read it, come back here and we'll talk more.


 
Ernie Wisner
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Evonne Smulders,
Your post was moved to a new topic.
I split this out
 
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Erica Wisner wrote:......... with a mass heater, it will stay warm for anything from hours to days after one brief fire session...........



Earlier Ernie had said that you get 1 hour of heating for 1" of mass. I am now a bit confused as I see this as saying that you would need 4 feet of mass for a couple of days heat. How long is a "brief" fire session to store a day of heating, and do I really need 2 feet thick mass?
 
Ernie Wisner
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"Earlier Ernie had said that you get 1 hour of heating for 1" of mass. I am now a bit confused as I see this as saying that you would need 4 feet of mass for a couple of days heat. How long is a "brief" fire session to store a day of heating, and do I really need 2 feet thick mass?"

think battery the longer you charge it the fuller it is to a limit; once you hit that limit it takes relatively little to recharge it or top up the charge. Two feet of mass is very little. and if you are building a bed, bench or something else it will almost be impossable to keep from having an appropriate amount of mass. if its water All of the water is mass. Air not so much.

Since we are discussing this have you read the book? its got a really nice explanation.
 
Roy Clarke
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Ernie Wisner wrote:
Since we are discussing this have you read the book? its got a really nice explanation.



The book? Maybe not, which book? I've got Ianto's book "Rocket Mass Heaters".
 
Ernie Wisner
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Thats the one Roy.
Erica says i should change the explanation i gave cause it confuses everyone (english to english translation is one of her strong points). OK Cob absorbs heat at 1 inch an hour it also releases heat at 1" an hour. depending on the thickness of the cob the peak heat absorbed while firing will reach the surface. so if i Have 9 inches of cob on the pipe and i fire the bench at noon I will get a burst of heat around 9:00 in the evening. the bench will still radiate heat as long as it is "charged".
Our little stove here needs to be fired about every 20 hours to keep the house at 70 degrees, we have 8 inches of Cob over the pipe. if I go to sleep and get up on time the house is a few degrees warmer when i take my shower and have my coffee. Then that burst of heat evens out and the house is back to 70 for most of the active day. in the evening about 11:00 we fire the stove for an hour before we go to bed (this is idealized to illustrate what i am trying to explain) then i get up and this happens.

now the way we fire our stove is we fire it for about one or two loads of wood an evening (about 2 cubic feet) depending on how warm we want the house for the evening (radiant heat off the barrel). As Paul can attest the stove can run me out of the house and make every one else sweat. We go to bed when the work is done for me thats around 9 or 10 for Erica its about 1 or 2 (she writes allot and does her best work when i am not bugging her). I get up usually around 7 and answer e mail and do business and household stuff. Erica needs 10 to 12 hours so she gets up a the appropriate time for her. The house maintains 70+ degrees with the burst happening around 2 in the morning (Erica gets Ice-cube feet and this helps me not hit the ceiling so hard when she puts her feet on me). When i wake up the house is 70+, when Erica wakes the house is 70+ and the cycle starts over again. Hopefully that clears up any confusion on this subject.
 
Roy Clarke
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Yes, that's clear. Just one thing, is your 2 cubic foot of wood the solid amount, or 2 cubic feet of logs/sticks/etc including airspace. If it's solid that means you use about 75 to 80 lb/day, is that correct? For say 100 day's heating, that's 4 tons which is over 2-1/2 cords.
 
Ernie Wisner
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Air included. if you look at the Vid Paul put up you can see the carrier i use. That thing full is what we burn for the day. currently we are living in a place where folks burn about 10 cord a heating season. so far we have not burned a cord and its February 23rd.
What i think is happening is folks are taking a general conservative estimate i am making (and I am being very conservative while some folks are giving numbers observed this is not wrong) i am myself building padding in because RMH's have to span a huge range of usage and building types. Some folks build carefully and others not so much.

By nature any estimate i make will be wrong; its a ball park. if you want a better number this is it it took me about 3 weeks to burn 75 lb of wood in our 6 Inch system and it took a person using a 3000 dollar airtight a single day. i came out with 7oz of ash and the air tight came out with well over 2 lbs. the air tight is run full open just like our RMH. The best i can do is give you our usage numbers and you can get on the net to look for the average burned in our area.
 
Roy Clarke
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Thanks for that. I guessed it probably included airspace otherwise you would be using loads of wood. If I could just get Mrs. RC to agree to a RMH, our heating bill could plummet. (Actually we'd save around $150 (equivalent) a year, but we could store many years of wood).
 
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Was another video ever done (part 2) to show the further greenhouse construction?
 
paul wheaton
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Another rocket mass heater vid


 
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