Rocket stoves in Greenhouses , our own forum topic

Michael R. : I'm doing a lot better than you, my biggest problem is that we adopted a feral Kitten ( no good deed goes unpunished) with "Worm Belly''
and the Difficult task to get him/her up to 6 weeks AND 2.2 pounds before our vet will dose her with standard medications ! This means sometimes we
need to help by squeezing her "Anal glands'' , and some times we have to cleanup after a bout of Diarrhea, the good news is the frequent baths has
cleared up a bad case of Fleas!

Life goes on, priorities are priorities, take them in the order you think appropriate, your fellow members will be here to respond to your needs ! For the
Good of the Crafts ! Big AL

Michael R. : I am doing much better than you! My Bigest problem is a new Feral Kitten that came into our lives complete with ''Worm Belly''! This means we are in self
imposed quarantine as we deal with alternate care needs to include squeezing his/her ''Anal Glands'' -to squeeze the crap out of her ! And alternately dealing with
leaking !

The good news is the frequent baths seems to have completely eliminated the Fleas !

1st, things 1st, take care of your primary duties and catch-up on the rest where you can ! For the Good of the Craft ! big AL

Alex K. : Yes to both heating and cooling, the last series of Paul W.s Audio logs (306~ish) Has a short discussion led y Ernie W. about Heat Tubes,

Using them to pump heat out of the Thermal Mass to a remote location, and the fact that they made the Alaskan Pipeline possible by reversing the
flow of heat from the pipeline down into the permafrost it was built on! A short mention was made on using heat tubes to pump heat

There is a proven history of building retaining walls and coffer dams out of mud using several Engineering tricks to freeze the mass and give a jello-like
Mass Rigidity !

This should be explored as a new topic ! For the good of the Crafts ! Big AL

Jeff F. : Your fellow members can only propose possible solutions to your problems, in the final event the choices are yours !

As designed your RMH will deliver a very efficient, very clean high temperature Burn, approximately 40 % of the total heat produced by Your Rocket
will be radiated off of the barrel. Without any Thermal Mass the remaining Hot exhaust gases 60% will be vented out of your Greenhouse at temperatures
dangerous to the poly-glazing ! As soon as your fire goes out you will experience instant cooling as you lose your radiant heat energy!

With a properly operating RMH and full Thermal mass The 60% that would otherwise go up the chimney will continuously re-radiate its stored heat energy
providing 12-24 hours worth of additional heating to carry your tender seedlings through the coldest part of the night !

Without the thermal Mass to provide this Buffering heat you will need to run the RMH near continuously to cover the lack of protection the Thermal Mass
provides!

A regular iron box stove that you can build a smoldering firkin to carry you through the night would actually serve you better !

The choice as I have said is yours, if you are contemplating Any Raised beds, I miss the point of not incorporating them into your RMH and recover the
remaining 60% of the heat energy produced by one of the most efficient Wood burning/heating units in the world ! For the Craft ! Big AL !

Big Al: I'm back!

You asked for photos of the window with measurements. Now you see inside and outside. We were planning to glass block this window once we had decided how the RMH piping would work going through the window opening. Thoughts?

Thanks.
Mike R.

Michael R. : Referring back to your original sketch, if you keep your original plans for Your RMHs location, we need to un-couple your floor and your Outside wall from
your Thermal Mass, otherwise you are going to be heating all outdoors. Because of that, I can see no easy way or any alternate set of building plans beyond the
Bonny convection bench done as a 8'' system! You will need some additional insulation along that wall starting at the window and running about 12' along that outside
wall, covered with ether sheet rock or hardy backer board and then an air gap/thermal break of at least 4'', a reflective aluminized fire stop and a further air gap of 6''
practical considerations on how to apply your finish coat of structural Cob to the Thermal mass may increase the gap as You deem necessary.

With the rocket in Your preferred location, the horizontal section of your Thermal mass starts at the end of a very generously shaped and sized Transitional area, flows
into and through your 1st clean out 'T' w cap, and then for just shy of 12 ft, turns toward the outside wall and returns via an elbow and a clean out to the rocket burner
base and a final clean out! Then up to the window, turns 90 degrees and passes out through the window, and a final elbow to rise like a sore thumb to a point above your
garages upper deck, ideally this location is on the downwind or lee side off your house during Your entire heating season.

When planning on the final height of this exterior chimney plan on the cost of pipe going 4 feet over the peak of your house, and a final storm cap! Then you can run the
stove pipe to just over everyones heads as they stand on the deck, and see if that is adequate !

With the 8'' RMH system we started out with approximately 50' of horizontal run remembering to subtract 5 feet for every 90 degree angle the gas has to flow through!

Because of your strongly stated desire to go out through the window and not pierce the membrane of the Garages upper deck we end up with about 24 feet of horizontal
piping and 25 feet of Elbows and 'Ts', with 2 sets of elbows close together ! this is about as doable as you can get with your preferred location !

Did you mention to E & E your desire to pass your stove pipe out through that window ?!, I ask this because this would not be a building plan that most people would pick
as their preferred way to run the piping and would probably affect the plans picked for you !

I understand your goals and can only suggest this plan as the most feasible with the restrictions you have on your job site ! Hope this is timely and helps, For the good

of the Craft! Think like Fire! Flow like a Gas! Don't be the Marshmallow! As always, your comments and questions are solicited And Welcome ! Pyrologically BiG AL

Bump

Big Al: Had family in over the weekend and went to a hog harvesting workshop Mon. and Tues., so, after getting caught up on chores and such, I'm back to ya.

One of the especially good things with having our younger son here this past weekend was to be able to kick around the RMH project with him. And probably the most useful realization that father-son discussion brought me was this: we've made some radical alterations to our garage and we're still tweaking parts of it as we get used to the idea of how we will now be using that space. As the weather slowly but surely gets colder (23 degrees last night) there are dynamics unfolding with this new space which might be worth paying real close attention to.

In other words, we don't know what this altered/upgraded space is going to do once it gets real cold. And for that reason, I'm choosing to postpone the RMH for the time being. The hiatus might allow for some of your wisdom to get through my thick skull and I'll eventually see the light about your good counsel, Big Al.

So, with much appreciation and thanks, I'm going to stay on the RMH sidelines for now and observe what's going on in my garage-to-greenhouse experiment and revisit the RMH project sometime closer to spring, I expect. I'll keep following the discussions, though, and comment when moved to!

Thanks again, Big Al, you're a credit to the craft -- no question !

Michael R. :O. K., Go to the [MY PROFILE] spot in the Permies toolbox and upgrade your personal information, who knows a Fellow member With Cob and RMH
experience may be a near neighbor ! For the Good of the Crafts Big AL

I did as you suggested, Big Al, and I'll be watching and reading what goes on here, too!

By the way, would you recommend Ianto Evan's book as a "good to read before you start" type of book?

Michael R. : Yes, with out any Hesitation, Let, Reservation or Mental Ambiguity on my part! There is no other book you can buy with more Rocket Stove, Pocket Rocket,
or Rocket Mass Heater information located in one place ! For the Good of the Craft ! Big AL

Paul Tofflemire wrote:Here is a picture of my riser hope its right

I am building an outdoor unit as well and have just poured my slab of concrete. Question: is the perlite mixed with clay and tamped level below the combustion unit? It's hard to see from the picture. Or is the combustion unit sitting on plain perlite held by some kind of crib?

Ianto suggests a perlite-clay mix which befuddles me because I have yet to get my hands dirty with the clay/dirt. Any photos/video of someone mixing perlite and dirt? Or do you have some close-ups of the layers of and below the perlite?

Thank yoU!!!

Remy O. I answered you question on the other forum Thread! Big AL

Paul Tofflemire wrote:Here is a picture of my riser hope its right

Another Q on this one: did your feed tube ashpit open up to the perlite layer? Or did you have a layer of brick under the burn tunnel that caught the feed tube ash?

allen lumley wrote:Remy Olson : Actually the ash pit performs two important functions, it is the 1st place that the almost talcum powder light Fly Ash can
settle out! A much more important function of the "Ash pit'' is in increasing the size of the Transitional Area of the burner base, The
depressed area below the lowest point of Your horizontal piping allows for more sweeping curves and a larger transitional
area! This helps prevent the hot exhaust gases from losing velocity from unwanted frictional contact with a floor in that location !

Generally, we tell new builders to load up their thermal mass with lists of rocks, making sure the rocks are well embedded and
covered with some cob ! A fellow member speaks of this as making Rock and Cob Lasagna, if rocks are the primary ingredient, you
will have to make less Cob.

Having said that generally it is better to make the entire Transitional area and 'Ash Pit' out of cob, you can stick in some hard wear
cloth for reinforcement and or chopped fiberglass, the hardware cloth will definitely be detectable to your finger tips telling you 'you
have cleaned up all that you should - Stop Now !

So because you will be cleaning that area up during yearly inspections and probably vacuuming out the T.A. / A. P. you will want to
make this area from cob with some reinforcement !

To burn off your barrel there are two tried and true routes, making up a Pocket Rocket, or two joining together (4 or 5) 30'' sections
of stove pipe notch deeply the piece that goes down to the bottom of the barrel and try again this time use smaller drier wood and
lots of it, also add some more new Clay mache` Keep plugging, you are getting closer ! Big AL

Awesome info Big AL. Thank you so much for these suggestions. I will line the bottom of the AP with cob & hardware cloth. Although this info ended up being useful for me, I think I wasn't specific enough as I would also like input on the AP below the feed tube itself. I laid an additional layer of cored brick (salvaged from a furnace) under the floor of the tunnel/combustion unit with no mortar. Do you think this needs cobbing/mortar? I'd think air would be a better insulator. This brings my AP to a depth of 4" -- https://flic.kr/p/pzqFNe (top view photo before lining bottom of feed tube AP w/hardware cloth+cob). Is this enough? I'd like to not make this any deeper as that means for me building up. My exit flue to the piping as it is is going to be angled downward to the middle of the benches.

Also, for insulation around the whole combustion unit was am planning to cob in as much perlite/clayslip insulation as I can as my unit is outdoors and I want as much heat as possible to go into the benches, not into the the cob around the combustion unit or leaving as radiant heat.

For the AP at the transition area to the benches (and APs in general) how are the clean out holes kept sealed up while you're running the fire? I don't see this at all in the Evans book.

For the pocket rocket to burn paint off the barrel do you recommend getting the fire going first (tipi style?) and then putting the 30" pipe right on top of it? Or off to the side of the fire? I'm having to buy stovepipe so I'd rather not notch up any of what I have as I have to use it in my benches and would think notching would impede flow? Any alternatives?

Remy : Your feed tube ash pit is a newbies crutch that you will outgrow, because it is so small the exposed edges of your bricks are going to take some
hard knocks and chip, You could make it bigger, I think I would just let it fill-up and form a firm crust of sintered flay ash!

Again the Transitional Area Ash Pit helps create a very important air gap below the start of your horizontal feed out to your thermal bench, this is where
you will install a stove pipe 'T' with a cap! You will also need at least one more at the base of your final vertical chimney !

With the Pocket Rocket you have a couple of lengths of pipe defending into the barrel to about 4''-5'' from the bottom of the barrel and this is the way
you load more wood ! So- start with a small fire, slap on the top before it gets to hot . the couple of lengths of external chimney will provide more than
sufficient draft, and you will see most of the barrel glow cherry red as the paper/clay mache` burns off! The pocket rocket will also help guarantee that
the barrel will not warp, and provide a way to check that it is still round. While the pocket rocket is a one trick pony, it is a great outdoor space heater
much loved by Preppers/ Zombie Hunter-Survivalists, the guys on the picket line ( it can and will set fire to blacktop) and Ice fishers !

IF the pocket rocket is not doable for what ever reason plan on getting the pieces together some day. My remark about notching your pipe was in favor
of having no Pocket Rocket and having to burn off your barrels paint by notching the bottom of the 10' length of pipe you put into your barrel this will
create air channels and the height of the chimney (4 Sections) Will draw nearly as well as the Pocket Rocket !

Finally you can always sand/grind off all the paint - Good eats at your house Hope this is timely and helps For the Craft ! Pyro-logically BIG AL

Remy : Good intelligent questions make my mind work a little harder, and the answers better and longer lasting ! The whole process is good therapy !
So- in no special order ! You can go to our sister site Richsoil.com, find and click on the [rocket mass Heaters] tab, and set and watch the whole
set of videos, while these were experiments by our host Paul W. and early days in his understanding of how RMHs work there instill much to learn!

Near the end is one way to burn off the barrel with out having made up a Pocket rocket, as the stove pipe is setting on the bottom of the Barrel and
can not be held on to, a couple of notches will provide the air channels to make the chimney draft, which it won't do if it slides down onto the bottom!

The pocket rocket uses the pipe that goes to within 4''-5'' of the bottom as its feed tube, this works much better than it sounds, build a small fire, drop
the top inlace before it gets to hot and the short external chimney will draw flames out of the barrel, at night you can see most of the Barrel growing
cherry red under your paper/clay mache`! no notch is needed !

The ash pit below the feed tube is a newbies crutch, and you are welcome to it almost every one eventually lets it fillip with a crust of sintered fly ash
in it that helps protect the brick that isn't there from damage when the next chunk of wood is dropped in ! A further tip, always load your small, finely
split, and very dry wood in the bigger end Down this will keep the wood from 'hanging -up' on each other and help the automatic feeding of the
Wood !

Hi Everyone,

I joined this site awhile ago and have been mostly just reading. After much research, reading the book, and planning, my husband and I built and modified a Harbor Freight Greenhouse kit to incorporate a rocket mass heater. After 3 days of "real world" use, I can mark the project as a success.

The RMH functions perfectly at a thermal mass temp of 90F and the pot on the top of the barrel steams extra humidity into the GH. We did not use conventional cob and rather used a brick/mortar for the thermal mass frame. The mass is a combination of ubanite and pea gravel. We used a high temp refractory cement (that we got for free) for all of the connections and the heat riser build.

The temps dipped to 32F over the last two evenings and the RMH and thermal mass kept the GH at 55F with no problem. Additionally, the condensation on the GH helped to keep the humidity up (we need to stay above 50%). Last night we were able to sleep through the night with no restocking the feed tube. The thermal mass combined with the heat from the barrel kept the temperature from dropping below 55F.

For a fire barrier, we used cement board in the corner. This protects the GH poly panels from melting. Yes, the barrels are coated with high temp stove paint.

Here are a few pictures.

Melissa Garner: It's been a couple of months. How are things going in the greenhouse? I'm inspired by your quick, seemingly functional implementation. Do you have any more pictures we could look at? Also, what size is the greenhouse, and what size is the riser (6", 8", etc.)?

Thanks.

J.D.

Hello to all,
This is my first post here on Permies and would love to say I'm honored to take part in such a wonderful community. We have a an aquaponics system here in SE TN that consists of 3000 sqft green house, all of which is deep water culture, about 1800 gallons of fish tank in the basement where we raise talapia. All in all we have about 7000 gallons of water running through our whole system. We can currently keep the water temperature @ 55 degrees during our cold spells but I would like to see those numbers closer to 70-75 degrees. Is there anyone warming this amount of water with a rocket mass heater? I'm highly interested in the automatic pellet feeder for automation but desperately want to get rid of the hot water heating element im currently spending money on to keep the fish disease free. I would love any input! Thank you in advanhce

Jeremiah Phelps : Welcome to permies.com. A word of warning please be very cautious in accepting ANYthing you see on U-Tube. there is a tremendous boatload
of crap to be found there !

Having said that The Aqua-ponics section is some better than most other U-tube sections!

Going to You-tube You need to enter web4deb which will take you to the Bigelow farms/web4deb channel, when you get there just below the very 1st video
you have the opportunity to click-on a [Playlists] tab, you are there to see the Rocket Mass Heater RMH Playlist- you probably will get lost in this site - you have
been warned !

Good luck/Good hunting ! Big AL

hello I'm completely new here and I'm putting my version of a rocket stove in my greenhouse right now. its a ten inch stove with a vermiculite and fire clay riser.the exhuast is 37 ft long and I'm not sure how tall of a stack i will put yet. when and if i can figure out how to put pictures up i will subject myself to some advice.

Jason Jerscheid : Welcome to permies.com, our sister site Richsoil.com and the Rocket, Wood stove, and Cob Forum Threads. W/ 29,000+
Fellow Members Worldwide you can expect to come here 24/7 and talk to someone who wants to talk about what you want to talk about. You will
stretch their mind as they stretch yours .

A little paperwork- look at the space around your name and L@@K at mine, We want to help you find that fellow member who is your near neighbor

Check out the link below :


https://permies.com/t/43625/introductions/Universal


This introduction was posted by a fellow member( with permission) not an Administrator, or staff member, There is no Trolling and the most important rule
is ''Be Nice'


A ten inch system, that must be a big green house ! Remember to always start your rocket off with small very dry fine split wood, It is important that the
incoming air from for feed tube is directed to your fuel wood, for that reason it may well be imperative for you to block off some of the top of your Feed
Tube opening to channel your air past Your fuel- Air that has not been entrained past the fire will have a tendency to cool the Burn tunnel and Heat Riser
preventing you from reaching maximum Temperatures !

Please do come back here and post pictures we would love to see your system ! For the Good of the Crafts ! Big AL

thanks for the welcome i see theres also some sawmill action around here and thats great i built one a few years ago and it comes in handy. heres some pis of what we have so far

Jason Jerscheid : Keep looking around : Many people who started with green houses have diversified and are doing combinations like chickens in an understory
to help boost temps, Aquaponics Vermi-culture and in ground models something new everyday !

With over 140 different forum threads, you will soon find your self following and responding to several Threads often per day !

A word of Warning There is a Large Boatload of Steaming CRAP out there on You-tube, please use due diligence before blindly following Anything you see There !

Having said that - You may want to look at the You-tube posts of Fellow member Rob T. who posts videos on you-tube as 'web4deb' see link Below :




For the Good of the Crafts ! Big AL

thanks for the links i have seen those and so many others. i have built a couple little ones like those but don't have the time to feed it all day. the one prior to this was an eight inch and it was close to what i was looking for. i should no here soon i plan on putting fire in it within the week.

Just a word of warning...

If you've been watching Bigelow Brook Farm's Youtube videos, you'll know he's been experimenting with an automatic pellet feeder for his RMH that heats his geodesic dome and aquaponics setup.

The other day, the pellet feeder got a blockage and it resulted in smoke filling his dome for about 12 hours. It killed back most of his plants, and the air pumps for his aquaponics system pumped the smoke into his water and it killed a load of his fish:


If you're putting a RMH in your greenhouse, it would pay to also put in a smoke detector just in case it develops a fault.

Any heating system it would be smart to go with both smoke and carbon monoxide detectors. In any enclosed area.

Hy Everyone,

We have built a rocket mass heater in our little 6 x 8 foot green house I know it is toooo big for it.
but I am planning on putting up a cover over 2 raised beds near the green house.
With this in mind we ran too exhausts out of the RMH going in two different directions.
We have not fired it up yet.
My question is: Is it OK to have two exhausts and should both of them be open?

You can certainly have two exhaust routes with a damper to shunt between them; two routes that are both open will always favor one more than the other and give you unbalanced heating. If you have sensitive dampers you may be able to balance the flows with practice.

Hello there is a new stove operates like a rocket stove only runs on pellets and is controllable has a water jacket attachment that will heat a 100 gallon tank of water up over 130 degrees and then the greenhouse guys are running a loop system from tank through their beds to heat the soil as well as heat of the stove in the green house. stove is made by Wiseway.
Gene

well i used my stove for a few weeks and the only problems were when the wind was ripping it would blow in my exhuast and fill the greenhouse with smoke cause i didn't have a chimney. also i haven't finished all the mass so it doest hold the heat. should be done before it gets cold again

Bjump !!! Jason how about an update ! Big AL

B-jump Big AL

Link Below :


https://permies.com/t/51336/rocket-stoves/Sulfuric-Acid-Greenhouse-RMH

This is my first ever RMH build. This is a solo experience, going slow, one baby step at a time.....
I have the current photos and a video of this Greenhouse RMH build on our fb page @ https://www.facebook.com/media/set/?set=a.429351400608072.1073741842.152019108341304&type=3

Test burn #1 was a fail. Heat riser was not sealed at the joint of the burn tunnel causing massive smoke blow back into greenhouse. Repair was made to heat riser and burn tunnel joint using fire and heat rated commercial mortar and more clay slip was added to all exterior joints of heater components at seams.

Test burn #2 was more of a success. However, I think I'm experiencing too much smoke blowback in the burn chamber. I realize that the system is still in open air and not completely sealed off with the heat mass but here are my questions at this point.
- is there an optimum length of burn tunnel. I've seen a lot of 24" tunnels so that is the length of this burn tunnel?
- could the burn tunnel length be a symptom of smoke blow back, again, I understand the system is not completely sealed yet
- what are some of the reasons for smoke blow back
- I don't see many folks using this fire rated red clay chimney liner as RMH material. Any ideas or experience, why???

Monday morning 1/18/16 7:00AM. Outside temp 27F, Inside Greenhouse temp 34F with no heat.
Test burn #3 fire started in about 3 mins. within 10 mins inside greenhouse temp was up to 42F. Still too much smoke bowback in burn chamber. I am using the construction lumber scraps so possibly the wood has moisture in it that is steaming back but no the flame is licking up about 6" in the air above the top lip of the burn chamber
- aahhh... clay chimney liner, I think I heard an expansion ---POP--- inside the riser barrel. Also, I see a crack forming at the corner of the burn chamber which is also the clay chimney liner.

I see you have learned by experience why clay chimney liners are not generally used in the combustion zone of an RMH
They can withstand a lot of heat, but not the fast temperature changes you get when firing an RMH. Some people have reportedly had success by first slicing the flue tile up the side or both sides so the tile can flex a bit while heating and relieve the stress.

You really need a full height chimney to operate an RMH in any but perfect conditions. It will work much better if it is insulated where it is outdoors, too. Sometimes that insulation makes the difference between working or not.

There is not so much an optimum length of burn tunnel as optimal proportions between parts of the combustion core. For a J-tube, it is generally recommended to have a ratio of 1:2:4 feed tube height to burn tunnel to heat riser. 24" burn tunnel length is probably good if other parts are proportional. What size (internal diameter) is your system?

I have seen some concerns with Greenhouse RMH operation side effects.

1 RMH pulls needed moisture out of greenhouse

2 pulls heat out of greenhouse after burn are complete

3 potentially pulls Co2 out of greenhouse since most RMH feed and air input are at the bottom and they may pull the heavier Co2 out of the greenhouse if it is significantly sealed.

4 high wood feed tending increases traffic in and out may decrease heat retention.


how could i reduce those concerns if i were to build one for my greenhouse?

1 i had an idea to address many of those concerns and if you have seen my home RMH system i created a standard 6" front port that i could plug into an access port in the floor to draw tepid air from the basement without removing heat, moisture and if i implemented a similar external port for the greenhouse it would also stop the heavier Co2 from being drawn out also.

2 a batch box or some sort of outside door that gives you access to the feed chamber would eliminate foot traffic and increase heat retention.


although i wouldnt mind building a greenhouse in the future, the idea i have on my plate now is to build a sun room connected to the south side of my house where my RMH exhaust chimney already resides. i will build a mass bench with loose soil in it and have a TEE coming off the current chimney with the ability to divert the exhaust through the loose soil and possibly take advantage of the Co2 for the plants.