I've watched all 4 parts to this build. Thank you. The knowledge I've gained from these 4 videos is more than all the rest I've watched combined. Now to start gathering materials.
You should show a timelapse of a couple of thermometers around the room starting at pre-ignition and ending at what is you're comfortable working temp. So we can see it in action.
Also would be interesting to have thermometer on exhaust and intake as well to see how much those increase over time. Plus run it with normal amount you would, but measure the amount, like 4 feet of 2x4 lumber with moisture content of X can be used to calculate how much potential energy there was to begin with.
Yes! What @Hellsong89 said! We need to know temps of room and exhaust at various times starting from cold, and including the temps when the heater seems to be maintaining a temperature for a period (an hour at the same exhaust and room temps would be informative)
There's something unbelievably satisfying about watching you do this kind of engineering. Just love all the in-depth knowledge and thought you put into this, and the great way you communicate it. Keep it up, and cheers for all the videos so far!
To code is always the best way. There might be a case some day where there's enough creosote build to cause a chimney fire (I know, rockets aren't SUPPOSED to, but...). Another: you sell the house. New homeowner puts in a standard stove. It's only a matter of time... Oh, and your on-off switch should have the 120V receptacle switched. Just because those small plug-in bricks are "Energy Vampires," drawing current (even if just a bit) whenever they are plugged in.
I built a rocket mass heater in my living room about the size of a small elephant and you hit the nail on the head today. To make it work correctly at least, you have to run it for a long time and that means like you said, sitting on the floor splitting wood and feeding it. The problem is, since mine is so big, I have to feed it about eight hours a day for three or four days in a row, before it will maintain a comfortable heat level in my living room. Live and learn. As for my “shop“ heater, I made a very tiny rocket stove out of air Crete and ceramic and I just let it roar next to my workbench. I used a nitrogen cylinder for the primary chimney enclosure and a run an inch and a half 14 gauge square steel tube out the side across the shop and up to the stack. The horizontal section of that has corrugated tin “fins” welded where they touch the pipe and The whole thing works like a champ and heat things up lickety-split. Of course, it looks like hell, so if you have a wife or girlfriend, it probably won’t fly. Edit: A Simpler fix to prevent down-draft from wind is to drill holes on the vertical sides of the chimney pipe from the top down about 12 inches. Next, weld a cap on top, which prevents wind and rain and snow and birds and so on from going down in there. Next, weld a piece of steel pipe, open at each end over the termination .6 inches each direction, past the drilled holes. When viewed from the top down, it would look kind of like Darth Vader‘s stealth fighter, kind of. Anyway, all the holes you drilled lets the exhaust out, but wind blowing from the side or down can’t hit the holes, so it doesn’t become a problem.
That just shows how bad they actually are. A normal masonry oven can be just filled once with 2 crates of wood, takes a couple hours to fully heat up and lasts for 2-3 days.
I don't know if you will read this, but I have had this idea for a long time though mine is different to a degree. I think if you use ceramic spray coating on the inside of your tank you will make it last for decades. This is the same principle used in turbine burn tubes. But I like the use of actual science and practical use of space, though I think you could have adapted a better intake design, and intake air to better burn, and also have a longer burn. I would love to collaborate with someone like you on a design. You have common sense and logic.
That works in a conventional system. But you don't want high flow exhaust gasses. You want it to move slowly so it has time to give up the heat to the "mass". That mass then will slowly radiate that heat into the room over the next 24+ hours.
@@jeffery19677 Yes you're correct. I mentioned the insulated flue for cases where so much heat is absorbed by the mass that by the time it reaches the exit that it's hard to draft out properly because it has lost so much heat. You only insulate the exterior part of the flue where it's exposed to cold outside air. It's a fix for people who build long runs & find that their burn is losing efficiency because of too slow a draft.
@@jeffery19677 "But you don't want high flow exhaust gasses." Which is the opposite of a rocket-stove. Also no, with a good stove you still want a decent flow - they are just smart enough to know how to make the exhaust-path long enough to give of most of its heat to the thermal mass before leaving the stove.
Cool video. Got a couple of ideas/suggestions. 1. If you block of parts of the vent towards where the wind blows from, I think it will create suction instead of blowing air "backwards" into the system. 2. About the exit-baffler: Water Pipes etc. should have the valve-handle so that it's "across" when it's closed and "along" the pipe when it's open. That way you can see with a glance it it's open or closed. Might be an idea for the baffler-handle. Almost forgot: Peace man.
The only problem with that is I don’t need to run it very long and it doesn’t usually get hot enough to cook stuff but I have put water on just to raise the humidity in the garage.
@@jairusofall If it's really that efficient, it's not surprising you don't need to run it long - but if its that efficient, it can't take all that long to boil water, can it? Even if it wouldn't be enough to stew something you could still brew a pot of coffee with it.
Very cool system. I built one last year. Quite different but exact same principle. You brought up where you get some smoke during initial start up... as you know these heaters are like an organism. They need a different kind of attention. I use a propane torch to pre-heat the exhaust. It primes them to get the heat moving in the direction we want. It only takes about 30 seconds and pretty much eliminates the smoke. I also have a damper just prior to exit of garage to close off cold air from cooling the heater down after a good burn.
I seem to recall a guy who did that propane pre-heat in a clean-out under his J-tube. I think you can also put a cleanout at the elbow where your stovepipe leaves the mass to go up the chimney, and light a really small fire - like a wadded-up page from a newspaper in that cleanout to warm up that vertical stretch of pipe. Then you can close the clean-out and light the rocket.
Stoked dude and PERFECT timing. Just been offered a Pot Belly stove by one neighbor and a wood pellet stove by another and neither are rocking my world (although I am grateful for the generosity and thank God for good neighborly relations). My shop is 36 x 32 and very high. It's freezing in there all winter event though it's insulated. Miserable quite frankly and I don't like the idea of $$$ on a high end electric system. I have wanted to build a mass heater for a while but have been too chicken shit. This has given me some confidence. Thank you so much mate.
I've been intrigued by these rocket mass heaters ever since I've come across them. I've watched all your videos on your heater. I like your more scientific and engineering approach to it. Thank you.
I've never been more proud of my name being on something but also I'm glad to give you more considering the fact you're making wicked entertainment....you deserved to at least be recognized for that.
you did the right thing building it to code, because someday someone else might use that existing chimney with a different apparatus that produces much hotter exhaust.
HI new here. You got me at "Hippies don't tell you this!!!" I love these rocket mass builds, hoping to one day build my own. Its nice to see one made without the beads and couch attached to it! Thanks for making me feel "Normal" for loving these!
I love the idea of a rocket stove. The trick to NEVER GET SMOKE INSIDE is to make a venturi tube outside encasing radially and parallel with the flu pipe with a enclosed motor at the top of pipe. This way you turn on the motor from the inside and never have to worry about going outside. This is only to start the stove when needed. This is the BOMB if you know what i mean. Good day too.
7:15 - you get more than just steam out of the exhaust, it's just that CO2 is an invisible gas. The lack of smoke is a lack of unburnt carbon, which is indicative of a very effective burn cycle. If you wanted steam only, you'd need to be burning hydrogen.
I've seen a few people talk about cold start issues. The 2 fixes I recall are having a bypass to get the chimney warm before starting to warm the mass or putting the chimney near the bell so it's heated that way. Folks generally want to keep electronics out of the mix because they're either using it as primary or emergency heat and in either case they want to be able to get it started in an emergency when they might not have power. Not an issue in your situation and even if it was you could run the fan with a power bank in a pinch.
I Really enjoyed this video. The ONLY negative thing I can say is, When you glued the Roof flashing/tube/cone/witches hat.... (please insert your local slang for this product/implement/component....here & save us all the corrections from the peanut gallery) You went ALL the way around the flange underneath. I was Always trained to leave the lowest point (bottom of the slope) OPEN with NO GLUE or adhesive (meaning; you glue ONLY the TOP side, the LEFT side & the RIGHT side yep, only glue those 3 sides) Because, IF there is any build up of water/moisture/condensation, it has some where to go/leave/exit/drip & NOT build up or back up over the actual roof hole & leak back into the structure. Is this a rare occurrence? I think so but, by the time you notice the leak inside the finished space, there has been enough damage to the unfinished space, you still have an even larger problem. I have asked many an Experienced roofer about this ideal/ideology/preference.... & have ALWAYS been given the same answer; Yes leave the bottom open to allow drainage.
@@danielstellmon5330 That may be the combustion temperature, but he said the exhaust stack was only warm to the touch. I imagine there will be a lot of condensate collecting in the chimney/heat exchanger.
I did the very same thing a few yrs ago...but uninsulated dryer vent in-tube, Was in basement of two story so after basement got warm had some reverse ex flow problem when the heat rose up inside house so we just stayed in basement when it was real cold and the fan stayed on the intake. Great cooking on top of barrel with spacer so metal would not get red and warp?crack?melt? Lill cheat used wood chips I covered that was delivered in fall free., just added a expanded metal guide to hold em in place so my sticks were like a spacer that held the guide in place until all burned and started over..
Have you thought about putting a little fan on the helium tank to circulate the air and help warm up your garage more and faster? It also sounds like to should cobble together something to help split down your wood faster. This is my favorite rocket stove design I've seen thus far. I plan to build my own house and want to incorporate a rocket stove into the design.
You could also put a Y joint on your air intake/fuel feed opening so that you can feed the fire without having to dismantle it every time. You'd need a cap for it and you'd still want to turn off the fan to get it going but it would make it a bit more functional. Might make it possible to construct some kind of automatic feeding hopper of previously processed wood too.
How do you remove ash from the combustion chamber? No matter how efficient the burn, there will be ash. I think I've worked it out, just like an ordinary wood burner, clean out the ash with a vacuum when it's cold.
Build a bypass chimney pipe you can send the exhaust through while you get it started and hot. Then when its hot switch the valve and send the exhaust thorugh the mass. It will give you faster and better stars.
Only improvement I can think of is a thermoelectric power supply for the fan running off the "waste" heat. Might still need the wall wart to get it started but once that helium tank warms up it would run itself. Yeah, I know, those are expensive. OTOH if you have enough scraps of the right metals laying around you can fabricate one. It won't be pretty but it will work. I don't *think* you'd have to bring in a cold sink from outside, should be plenty of energy available in the temperature differential between the tank and the room air.
I have an old solar panel on the roof of my garage that keeps a bank of old car batteries charged up. I use them to charge my cordless tools, run the lights, and run the fan on my wood forge.
I would add a "vertical feeding tube" for longer pieces of wood, that opens to the fire chamber and is air tight when the pieces of wood are installed.
Nice job! Rocket stoves are a thinking person's woodstove... and even though mine is 4 years old... I keep messing with it, make new drawings, and will build version 2.0 at some time. There's so many innovations here on YT. I built a 6 inch flue rocket. It is a free-standing unit, utilizing a 55 gallon barrel. It is, internally, like the hippie rockets (hell, I am a hippie) only the riser is made from insulated firebrick (the most expensive component). The exhaust goes out of the bottom, and into a 15 foot long mass of cement blocks and crushed stone, at floor level. From there the exhaust goes up and out of the basement, through the wall, and outside through that super-expensive stainless insulated flue pipe, gifted to me by a friend (free is for me). My indoor flue temps, at building outlet, are similar to yours... rarely 150°... more often 120°. My stove is for heating my basement workshops, and the house above... the burn chamber is 8 x 8 inches,therefore, I can burn standard cordwood. From my experience, it looks to me as if smaller rockets are more efficient, and hotter... but most smaller ones are to heat workshops/garages, not entire homes... all I know is that I love using it. I was happy to get the insulated flue because condensation would run into the house, and black mung would run across the floor... at least it is water soluble, and cleans up with soap and water... I put a T flue pipe outside, at the bottom, with a seepage hole in a cap. This keeps all condensation outside. One thing I want to do is figure out an automatic lid, outside, that would close when the stove shuts down. I believe a lot of my mass heat is going up the chimney... and that the cold air, coming back down the chimney, cools the mass. I go through a wheelbarrow of wood per day. When I had a standard woodstove, I'd go through 3 wheelbarrows of wood... My rocket is on my channel if you'd like a look. The video is with the smaller 4.5 x 4.5 burn chamber... I've been using it for 4 seasons, and have had zero creosote buildup.
So.. you go pretty much against anything that would make it a rocket stove and have built something similar to a normal stove how the rest of the world uses them - just a bit less efficient.-
Any kind of steel used in the burn chamber is doomed to failure. The kind of heat created by a system like this will create spalling of the metal. Were you to take your system apart, you might find that significant erosion has already occurred. Masonry or refractory materials are the only thing capable of standing up to the extreme temps of a highly efficient wood-burning device, over numerous firings. Also, there is a simple bell design, with metal inserts in the top, that would take up about half the space of what your unit does, and give off just as much heat.
Jason could you please post a link of the simple bell design with metal insert you are mentioning? That would be awesome as I am planning to build a RMH but I don't have a lot of space. Thanks in advance
@@vivanicola Do a search for Paul Wheaton, tiny house rocket mass heater. Imagine that unit with metal panels on the front and the sides of a squared bell, at the top of the masonry structure. You are essentially building mass on top of a Finnish contra-flow masonry stove, with metal panels to radiate immediate heat. The masonry mass will store heat for slow release after it gets warmed up. Instead of having the mass to the side of your burn chamber, it sits on top of it.
I think you have done a good job here I think the reason you can use metal in the burn tunnel is you have a micro system, I think if you had an 8 inch system metal would not last. I don’t think you give the hippie’s enough credit, I did laugh when you kept bringing them up because I think too many of us are over the top on political correctness, I Have been to Ernie and Erica’s place and seen their rocket mass heater they are probably the most experienced builders alive. And they are both extremely well educated about fire and thermodynamics you keep mentioning. Anyway I love the video thanks for sharing, thumbs up from me dude!
If your worried about the cold dense air pushing it's way back down the chimney it seems the best place for the exhaust to exit your garage would be near the floor. This would also condense the warm moist air in the system if any at floor level so it wouldn't run down into the system. What do you think?
I think you still need the exhaust to go up x feet for y feet of horizontal distance from the burn chamber, according to lore. But I think if you built a proper rocket, it will pretty much only go one way, once it's going, also according to lore.
I think the reason they say you can't use steel is because the heat causes the steel to oxidize very quickly. You might be able to just replace it every few years to prevent that.
it's all about the insulated chimney column to really get things flowing in the right direction, especially in really cold weather and especially when you add vertical column height to it. Also, the ease of operator input is more of a major factor than one might first imagine. pellet stoves will self feed for hours, a long feed pipe with scraps of sticks that will slide down on their own might also self feed for hours.
Darksunrise there’s videos on how to make them too, usually it requires welding and a pretty adequately equipped workshop so it might be a cheaper one-off purchase to get a small one from the store. Also if you own a chainsaw there’s attachments I’ve seen that act as a rough marker for the length of the logs you’re cutting. It’s literally a stick that screws into your saw that pokes off about a foot from the blade so you can measure what you cut at the same time.
Have you considered adapting the burn chamber to have a pellet input? There are some gravity feed pellet systems. It could simplify the annoyance of having to tend the fire so much, but it would also add an expense in pellets. Nice design though.
A chimney installer once told me that you should never reduce your chimney to the outside since it created compression in your exhaust and and is counter productive to your flow! That way starting a range exhaust fan can easily reverse you flow to inside your house or your garage. In the case of a garage letting the door open could also cause the flow to reverse.
Would a hopper with wood chips help the fueling side of this project? That if your so inclined is even something you could automate say... One of those timed release kibble setups for dogs but that feeds wood chips into your burner.
I have been told if the chimney doesn't burn hot enough you get creosote build up, if I understand that right then do you have build up and what do you do about it
Hmmmm I may have to build that. As far as making sticks small enough to fit in there. Get a 14" bandsaw, and decide on the dimensions and start cutting. I probably already have 2 or 3 buckets of pen blanks that would fit right in there. One suggestion I would have is to add a small computer fan on the exhaust as well to ensure you get it going......
Congrats, you just invented an inter-cooled, super charged wood stove. This is quite possibly the most over-engineered wood stove in history in the best way possible
the hippies typically say you cannot make your combustion chamber out of steel, but i believe that's only true for the larger systems, like ones with 8" cross sectional flow area. the temperatures in those are much higher, and the steel will rust out within a few hours of running
I was concerned about creosote build up in the heat exchanger but I see in another comment that you have pulled it apart and haven't seen that to be an issue. Makes me wonder why I have to clean my chimney twice a year when it's a straight shot up.
Hey, hippie here. If you have a predominant wind direction you should point the open end of you intake towards it, and the exhaust outlet away from the wind to generate a flow. If you want to get serious about harnessing that power also, you could stick a funnel on the intake side, and build a little venturi system on the outlet. That would negate the need for a computer fan, and possibly oversupply your stove with air (computer fan is a genius idea btw. I've heard that some fossil fuel based electricity generating stations preheat their intake air by drawing it down around the exhaust chimney, which results in such an efficient heat transfer that they then have to use fans to push the cold exhaust air out of the chimney. Similar to what you're doing here. Good Job)
One thing you did not mention is carbon build up in the heat exchanger and the exhaust pipe. Because the piping following the burning chamber is so cold the residue carbon will condense before it can burn. These build ups, once big enough can burn off and turn your exhaust red hot, so either clean it sometimes or be aware of a possible run-away.
Oh yes…we’ve had all kinds of trouble getting the old chimney to draw. Not even making the firebox smaller, could help it draw. Not even sticking a fireplace insert into there helped-it was a disaster. That’s another reason we bot a Liberator rocket stove + a chimney sleeve, besides how beautifully efficient these are. I used a drier vent to bring air into the air intake on it…& had to put a damper in that, to adjust air flow in. But maybe I’ll try insulating the intake, too…had no idea cold air would help the burn!? When installing the sleeve, I had to remove the recommended insulation wrapped around the sleeve, to fit it up thru the chimney, & simple-stuff it around the sleeve at top & bottom of chimney. Your cold air intake going direct into your feed tube, seems inconvenient….if it went into the side to of the feed tube, you could leave it connected, & be able to add wood more easily. Could even use a 4” pipe section to extend the feed tube then, allowing more sticks to be put into it, so you didn’t need to keep adding fuel so often.
Add a rotating chimney exhaust tip that the wind turns like a weather vane to prevent downdraft. If made correctly you could use venturi effect to create draft when the wind is blowing.
When you said you were going to do your outtake in front of the stove, but wouldn't because you felt like you were going to be burnt. Just had an idea, maybe put a cage around the helium tank to prevent anything falling on the tank? Air/heat could still go through, but would stop anything from falling on it and catching fire.
I would recommend double wall pellet stove pipe because it has a stainless steel liner in it. It comes in 3 and 4 inch sizes. Also 6” triple wall stove pipe could be very useful here. but, good job looks good!
If you could have... Would you have made the intake longer so you would be able to load more fuel at a time??? I am thinking you would also be able to have bigger intervals before you had to add fuel..?
You could probably use peltier effect plate to run your PC fan once it gets warmer enough so that the system is keeping itself going instead of puling power from the wall
For a while it didn't sound like the furnace was vented to the outside. Was worried about Carbon monoxide poisoning. But you don't want the exhaust temperature too low. You want the exhaust to be hot enough to rise up and out. Get a CO monitor.
What's the difference between forcing cold air up, and forcing hot air down? How much cooler could the hot air be once it gets to the down tube? I can't imagine it would be significant, it's 6 inches from the to of the heat exchanger.
I have just built a new barn and intend on using a rocket mass heater, so I have a couple questions. Well more than that, but I’ll limit myself. Have you ever thought about reversing the air flow in the summer to cool the mass? I guess in your case you would not have to reverse the air flow. What I am saying is force the cool night air through the mass to cool it. Then the warmer air in the room would go into the cooler mass in the day time and cool the room. The second thought I have is an odd fuel. I live on the North American plains and we have an abundance of rag weed ( tumble weeds) which are flammable. I am going to harvest them while they are green and bundle them up tight so they will fit in the rocket. I am not sure what to expect . Do you think I am chasing my tail?
You could take the head off a lawnmower engine and bolt a small wedge to the piston. Then make a jig to hold 6 or 8” blocks to be split. Drive the engine with an electric motor and split very fast.
Would insulating the drop pipe from the rockets tank into the mass reduce the amount of instant radiant from that amount of surface area and put it into the mass possibly helping the draft a little in the process. The surface area of the drop pipe could be 1/5th of the surface of the tank itself (not going to take time to do that math). Maybe a header wrap or the fiberglass stuff you used on the primary burn chimney and leave the joints exposed so you can still remove it easily. Although I think your new outlet chimney can change the issues you had. I would love to see it work without the 12volt fan except for start up times. Also dollar store aluminum tape can hold up to 700F I use it on my woodstove outlet flue joints before the masonry chimney and the joining of the flue to the stove since everyone's 8 inches isn't exactly the same (0.o) and I didn't want to build a shim. I take this off twice a burn season at the stove to clean things and have seen it peak to 700F when I fire it off sometimes before I engage the bypass to the cat chamber and all is well with it. I know what you mean by scavenging all the heat my stove full burn the box is +-500F with the cat up to temp 1200-1400F my flue temps drop to 250F versus 500+ with the bypass open at full burn. 700lbs of cast iron and tossed some old chevy heads on it for good measure. I might not be as efficient with the wood but for a woodstove I think that is pretty good being my flue temp gauge is only 3 linear feet from a 1400 degree cat the design makes use of expansion just after the cat there is a chamber before the flue this somehow lets a majority of that 1400F radiate through the walls and top plate and only put 250F up the flue that is internal smoke path temp not wall of flue temp. Since I have an outdoor masonry chimney I wouldn't want any less than 250F going out.
great video .. excellent theory and practical demo . first time I have seen a sort of torroidal burn chamber fabrication . I have my torroidal vortex design laying horizontal where it leaves the burn chamber the riser exits the centre of the donut shaped refractory cast torroidal secondary burn zone .
My understanding is that you want the burn chamber itself to lose heat fairly freely, and not get super-hot, so that the insulated riser, of refractory brick/concrete/metal where the refractory temperatures are achieved.
Yeah...Those damn hippies and their smarty pants awesome and cheap heating idea that this guy hasn't been able to figure out but is certain that his occasionally failing attempt to duplicate it is better. LOL
Hey... easy... this hippie is a techno-geek... welder/craftsman/machinist/carpenter/engineer, who understands thermodynamics, amongst many other subjects... including psychology... Peace
Man, I would love an update on your heater to know how it's holding up and if the steel held up or not. Or just an update in general, you haven't posted in a long time
The comparison with propane at the end is a little misleading. It sounds like you're suggesting the rocket mass heater is more efficient than the propane heater because the rocket mass heater keeps the room warmer longer. But that's a question of convenience, not of efficiency. After all, you could create a propane mass heater if you wanted, and that would keep the room warm for a long time, too.
I hate to tell you this, but, I think we’re on the same wavelength. That being said, I’m old and had trouble keeping up with you. Is there any way I could get a semi-detailed drawing? You’ve done a great job. Thanks 👏🏻👏🏻
I've watched all 4 parts to this build. Thank you. The knowledge I've gained from these 4 videos is more than all the rest I've watched combined. Now to start gathering materials.
Wow, when you first built this I was very interested in the long time run of this, I love that you came back to it!
Good job on the engineering of it!
You should show a timelapse of a couple of thermometers around the room starting at pre-ignition and ending at what is you're comfortable working temp. So we can see it in action.
Also would be interesting to have thermometer on exhaust and intake as well to see how much those increase over time. Plus run it with normal amount you would, but measure the amount, like 4 feet of 2x4 lumber with moisture content of X can be used to calculate how much potential energy there was to begin with.
Yes! What @Hellsong89 said! We need to know temps of room and exhaust at various times starting from cold, and including the temps when the heater seems to be maintaining a temperature for a period (an hour at the same exhaust and room temps would be informative)
There's something unbelievably satisfying about watching you do this kind of engineering. Just love all the in-depth knowledge and thought you put into this, and the great way you communicate it. Keep it up, and cheers for all the videos so far!
To code is always the best way. There might be a case some day where there's enough creosote build to cause a chimney fire (I know, rockets aren't SUPPOSED to, but...).
Another: you sell the house. New homeowner puts in a standard stove. It's only a matter of time...
Oh, and your on-off switch should have the 120V receptacle switched. Just because those small plug-in bricks are "Energy Vampires," drawing current (even if just a bit) whenever they are plugged in.
I built a rocket mass heater in my living room about the size of a small elephant and you hit the nail on the head today. To make it work correctly at least, you have to run it for a long time and that means like you said, sitting on the floor splitting wood and feeding it. The problem is, since mine is so big, I have to feed it about eight hours a day for three or four days in a row, before it will maintain a comfortable heat level in my living room. Live and learn.
As for my “shop“ heater, I made a very tiny rocket stove out of air Crete and ceramic and I just let it roar next to my workbench. I used a nitrogen cylinder for the primary chimney enclosure and a run an inch and a half 14 gauge square steel tube out the side across the shop and up to the stack. The horizontal section of that has corrugated tin “fins” welded where they touch the pipe and The whole thing works like a champ and heat things up lickety-split.
Of course, it looks like hell, so if you have a wife or girlfriend, it probably won’t fly.
Edit: A Simpler fix to prevent down-draft from wind is to drill holes on the vertical sides of the chimney pipe from the top down about 12 inches. Next, weld a cap on top, which prevents wind and rain and snow and birds and so on from going down in there. Next, weld a piece of steel pipe, open at each end over the termination .6 inches each direction, past the drilled holes.
When viewed from the top down, it would look kind of like Darth Vader‘s stealth fighter, kind of.
Anyway, all the holes you drilled lets the exhaust out, but wind blowing from the side or down can’t hit the holes, so it doesn’t become a problem.
That just shows how bad they actually are.
A normal masonry oven can be just filled once with 2 crates of wood, takes a couple hours to fully heat up and lasts for 2-3 days.
I don't know if you will read this, but I have had this idea for a long time though mine is different to a degree. I think if you use ceramic spray coating on the inside of your tank you will make it last for decades. This is the same principle used in turbine burn tubes. But I like the use of actual science and practical use of space, though I think you could have adapted a better intake design, and intake air to better burn, and also have a longer burn. I would love to collaborate with someone like you on a design. You have common sense and logic.
From what I understand, super-heating the incoming air increases burn efficiency and insulating the exhaust flue improves the flow of exhaust gases.
That works in a conventional system. But you don't want high flow exhaust gasses. You want it to move slowly so it has time to give up the heat to the "mass". That mass then will slowly radiate that heat into the room over the next 24+ hours.
@@jeffery19677 Yes you're correct. I mentioned the insulated flue for cases where so much heat is absorbed by the mass that by the time it reaches the exit that it's hard to draft out properly because it has lost so much heat. You only insulate the exterior part of the flue where it's exposed to cold outside air. It's a fix for people who build long runs & find that their burn is losing efficiency because of too slow a draft.
@@jeffery19677 "But you don't want high flow exhaust gasses." Which is the opposite of a rocket-stove.
Also no, with a good stove you still want a decent flow - they are just smart enough to know how to make the exhaust-path long enough to give of most of its heat to the thermal mass before leaving the stove.
Cool video.
Got a couple of ideas/suggestions.
1. If you block of parts of the vent towards where the wind blows from, I think it will create suction instead of blowing air "backwards" into the system.
2. About the exit-baffler: Water Pipes etc. should have the valve-handle so that it's "across" when it's closed and "along" the pipe when it's open. That way you can see with a glance it it's open or closed. Might be an idea for the baffler-handle.
Almost forgot: Peace man.
Put a stove burner on top of the helium tank and then you could make soup and/or coffee while you're running the heater.
Making instant ramen with a wood fired heater is a video idea.
should put one of those heat powered fans on it to produce airflow in the room for free!
right... a small(or big) stirling engine with a fan attachment will do the trick or a steam powered fan on the exhaust
The only problem with that is I don’t need to run it very long and it doesn’t usually get hot enough to cook stuff but I have put water on just to raise the humidity in the garage.
@@jairusofall If it's really that efficient, it's not surprising you don't need to run it long - but if its that efficient, it can't take all that long to boil water, can it? Even if it wouldn't be enough to stew something you could still brew a pot of coffee with it.
Very cool system. I built one last year. Quite different but exact same principle.
You brought up where you get some smoke during initial start up... as you know these heaters are like an organism. They need a different kind of attention. I use a propane torch to pre-heat the exhaust. It primes them to get the heat moving in the direction we want. It only takes about 30 seconds and pretty much eliminates the smoke. I also have a damper just prior to exit of garage to close off cold air from cooling the heater down after a good burn.
I seem to recall a guy who did that propane pre-heat in a clean-out under his J-tube. I think you can also put a cleanout at the elbow where your stovepipe leaves the mass to go up the chimney, and light a really small fire - like a wadded-up page from a newspaper in that cleanout to warm up that vertical stretch of pipe. Then you can close the clean-out and light the rocket.
Stoked dude and PERFECT timing. Just been offered a Pot Belly stove by one neighbor and a wood pellet stove by another and neither are rocking my world (although I am grateful for the generosity and thank God for good neighborly relations). My shop is 36 x 32 and very high. It's freezing in there all winter event though it's insulated. Miserable quite frankly and I don't like the idea of $$$ on a high end electric system. I have wanted to build a mass heater for a while but have been too chicken shit. This has given me some confidence. Thank you so much mate.
I've been intrigued by these rocket mass heaters ever since I've come across them. I've watched all your videos on your heater. I like your more scientific and engineering approach to it. Thank you.
I've never been more proud of my name being on something but also I'm glad to give you more considering the fact you're making wicked entertainment....you deserved to at least be recognized for that.
you did the right thing building it to code, because someday someone else might use that existing chimney with a different apparatus that produces much hotter exhaust.
HI new here. You got me at "Hippies don't tell you this!!!"
I love these rocket mass builds, hoping to one day build my own. Its nice to see one made without the beads and couch attached to it!
Thanks for making me feel "Normal" for loving these!
Very interesting, I hadn't heard of this until now. So rad!
For the wind blowing into chimney problem, fit a H Cap/cowl, this creates vacuum as wind blows, so more wind, more vacuum
On today's episode, I'm cutting a hole in my goddamned roof.
Balls of steel.
Oh wow, I didn't expect to see you here!
Walcom S7 I hope his parents don’t kill him over that.
I love the idea of a rocket stove. The trick to NEVER GET SMOKE INSIDE is to make a venturi tube outside encasing radially and parallel with the flu pipe with a enclosed motor at the top of pipe. This way you turn on the motor from the inside and never have to worry about going outside. This is only to start the stove when needed. This is the BOMB if you know what i mean. Good day too.
7:15 - you get more than just steam out of the exhaust, it's just that CO2 is an invisible gas. The lack of smoke is a lack of unburnt carbon, which is indicative of a very effective burn cycle. If you wanted steam only, you'd need to be burning hydrogen.
I've seen a few people talk about cold start issues. The 2 fixes I recall are having a bypass to get the chimney warm before starting to warm the mass or putting the chimney near the bell so it's heated that way. Folks generally want to keep electronics out of the mix because they're either using it as primary or emergency heat and in either case they want to be able to get it started in an emergency when they might not have power. Not an issue in your situation and even if it was you could run the fan with a power bank in a pinch.
Fantastic update. Have been hoping to see a followup since the original series. Great work and chuffed that all your hard work payed off.
I Really enjoyed this video. The ONLY negative thing I can say is, When you glued the Roof flashing/tube/cone/witches hat.... (please insert your local slang for this product/implement/component....here & save us all the corrections from the peanut gallery) You went ALL the way around the flange underneath. I was Always trained to leave the lowest point (bottom of the slope) OPEN with NO GLUE or adhesive (meaning; you glue ONLY the TOP side, the LEFT side & the RIGHT side yep, only glue those 3 sides) Because, IF there is any build up of water/moisture/condensation, it has some where to go/leave/exit/drip & NOT build up or back up over the actual roof hole & leak back into the structure. Is this a rare occurrence? I think so but, by the time you notice the leak inside the finished space, there has been enough damage to the unfinished space, you still have an even larger problem. I have asked many an Experienced roofer about this ideal/ideology/preference....
& have ALWAYS been given the same answer; Yes leave the bottom open to allow drainage.
Interesting design. If you build another, do consider a batch box below the external intake.
All of the information I wanted, well ordered, good video.
Thanks for all of the effort and being so clear.
How can you clean out the ashes and creosote that would accumulate in the exhaust chambers over time?
If the fire burns hot enough there are no ashes. If I remember correctly he said that the target temperature is 1200 degrees.
@@danielstellmon5330 That may be the combustion temperature, but he said the exhaust stack was only warm to the touch. I imagine there will be a lot of condensate collecting in the chimney/heat exchanger.
I did the very same thing a few yrs ago...but uninsulated dryer vent in-tube, Was in basement of two story so after basement got warm had some reverse ex flow problem when the heat rose up inside house so we just stayed in basement when it was real cold and the fan stayed on the intake. Great cooking on top of barrel with spacer so metal would not get red and warp?crack?melt? Lill cheat used wood chips I covered that was delivered in fall free., just added a expanded metal guide to hold em in place so my sticks were like a spacer that held the guide in place until all burned and started over..
Have you thought about putting a little fan on the helium tank to circulate the air and help warm up your garage more and faster? It also sounds like to should cobble together something to help split down your wood faster. This is my favorite rocket stove design I've seen thus far. I plan to build my own house and want to incorporate a rocket stove into the design.
That is really cool. Gotta say getting something so efficient out of 'trash' is so Fallout/you lol
I really enjoyed watching you make the heater, glad to see it’s efficient
You could also put a Y joint on your air intake/fuel feed opening so that you can feed the fire without having to dismantle it every time. You'd need a cap for it and you'd still want to turn off the fan to get it going but it would make it a bit more functional. Might make it possible to construct some kind of automatic feeding hopper of previously processed wood too.
How do you remove ash from the combustion chamber? No matter how efficient the burn, there will be ash. I think I've worked it out, just like an ordinary wood burner, clean out the ash with a vacuum when it's cold.
Build a bypass chimney pipe you can send the exhaust through while you get it started and hot. Then when its hot switch the valve and send the exhaust thorugh the mass. It will give you faster and better stars.
Only improvement I can think of is a thermoelectric power supply for the fan running off the "waste" heat. Might still need the wall wart to get it started but once that helium tank warms up it would run itself.
Yeah, I know, those are expensive. OTOH if you have enough scraps of the right metals laying around you can fabricate one. It won't be pretty but it will work.
I don't *think* you'd have to bring in a cold sink from outside, should be plenty of energy available in the temperature differential between the tank and the room air.
There are some Stirling engines that could create that level of electricity. There are even non-electric Stirling engine fans
I have an old solar panel on the roof of my garage that keeps a bank of old car batteries charged up. I use them to charge my cordless tools, run the lights, and run the fan on my wood forge.
I would add a "vertical feeding tube" for longer pieces of wood, that opens to the fire chamber and is air tight when the pieces of wood are installed.
Excellent. And you did a great job on your overkill exhaust improvement.
Nice job! Rocket stoves are a thinking person's woodstove... and even though mine is 4 years old... I keep messing with it, make new drawings, and will build version 2.0 at some time. There's so many innovations here on YT.
I built a 6 inch flue rocket. It is a free-standing unit, utilizing a 55 gallon barrel.
It is, internally, like the hippie rockets (hell, I am a hippie) only the riser is made from insulated firebrick (the most expensive component).
The exhaust goes out of the bottom, and into a 15 foot long mass of cement blocks and crushed stone, at floor level. From there the exhaust goes up and out of the basement, through the wall, and outside through that super-expensive stainless insulated flue pipe, gifted to me by a friend (free is for me). My indoor flue temps, at building outlet, are similar to yours... rarely 150°... more often 120°.
My stove is for heating my basement workshops, and the house above... the burn chamber is 8 x 8 inches,therefore, I can burn standard cordwood.
From my experience, it looks to me as if smaller rockets are more efficient, and hotter... but most smaller ones are to heat workshops/garages, not entire homes... all I know is that I love using it.
I was happy to get the insulated flue because condensation would run into the house, and black mung would run across the floor... at least it is water soluble, and cleans up with soap and water...
I put a T flue pipe outside, at the bottom, with a seepage hole in a cap. This keeps all condensation outside.
One thing I want to do is figure out an automatic lid, outside, that would close when the stove shuts down. I believe a lot of my mass heat is going up the chimney... and that the cold air, coming back down the chimney, cools the mass.
I go through a wheelbarrow of wood per day. When I had a standard woodstove, I'd go through 3 wheelbarrows of wood...
My rocket is on my channel if you'd like a look. The video is with the smaller 4.5 x 4.5 burn chamber...
I've been using it for 4 seasons, and have had zero creosote buildup.
So.. you go pretty much against anything that would make it a rocket stove and have built something similar to a normal stove how the rest of the world uses them - just a bit less efficient.-
Any kind of steel used in the burn chamber is doomed to failure. The kind of heat created by a system like this will create spalling of the metal. Were you to take your system apart, you might find that significant erosion has already occurred. Masonry or refractory materials are the only thing capable of standing up to the extreme temps of a highly efficient wood-burning device, over numerous firings. Also, there is a simple bell design, with metal inserts in the top, that would take up about half the space of what your unit does, and give off just as much heat.
Jason could you please post a link of the simple bell design with metal insert you are mentioning? That would be awesome as I am planning to build a RMH but I don't have a lot of space. Thanks in advance
@@vivanicola Do a search for Paul Wheaton, tiny house rocket mass heater. Imagine that unit with metal panels on the front and the sides of a squared bell, at the top of the masonry structure. You are essentially building mass on top of a Finnish contra-flow masonry stove, with metal panels to radiate immediate heat. The masonry mass will store heat for slow release after it gets warmed up. Instead of having the mass to the side of your burn chamber, it sits on top of it.
I think you have done a good job here I think the reason you can use metal in the burn tunnel is you have a micro system, I think if you had an 8 inch system metal would not last. I don’t think you give the hippie’s enough credit, I did laugh when you kept bringing them up because I think too many of us are over the top on political correctness, I Have been to Ernie and Erica’s place and seen their rocket mass heater they are probably the most experienced builders alive. And they are both extremely well educated about fire and thermodynamics you keep mentioning. Anyway I love the video thanks for sharing, thumbs up from me dude!
If your worried about the cold dense air pushing it's way back down the chimney it seems the best place for the exhaust to exit your garage would be near the floor. This would also condense the warm moist air in the system if any at floor level so it wouldn't run down into the system. What do you think?
I think you still need the exhaust to go up x feet for y feet of horizontal distance from the burn chamber, according to lore. But I think if you built a proper rocket, it will pretty much only go one way, once it's going, also according to lore.
I think the reason they say you can't use steel is because the heat causes the steel to oxidize very quickly. You might be able to just replace it every few years to prevent that.
it's all about the insulated chimney column to really get things flowing in the right direction, especially in really cold weather and especially when you add vertical column height to it.
Also, the ease of operator input is more of a major factor than one might first imagine. pellet stoves will self feed for hours, a long feed pipe with scraps of sticks that will slide down on their own might also self feed for hours.
Just thinkin, if you put a 90° bend on the exhaust and point it down wind, would it help create a draw?
Have you considered getting/making a small wood chipper to avoid having to spend the hour or so each day breaking up the fuel?
Darksunrise there’s videos on how to make them too, usually it requires welding and a pretty adequately equipped workshop so it might be a cheaper one-off purchase to get a small one from the store.
Also if you own a chainsaw there’s attachments I’ve seen that act as a rough marker for the length of the logs you’re cutting. It’s literally a stick that screws into your saw that pokes off about a foot from the blade so you can measure what you cut at the same time.
Love it thanks for the update
Ultimate upgrade auto feed and start up so you can program it to start for an hour or two every 12 hours
You should have payed those hippies the money to learn how to do it right hahahaha
Nice setup. That dense cold air is the ticket.
Have you considered adapting the burn chamber to have a pellet input? There are some gravity feed pellet systems. It could simplify the annoyance of having to tend the fire so much, but it would also add an expense in pellets. Nice design though.
thanks for the tips! upped my game for sure... now it's time for me to learn to weld.
I love your style. Very well made video
3:23 My first time here. Do you have a video of the nautilus chamber?
Thank you Jairus of All! Your video was helpful and informative.
A chimney installer once told me that you should never reduce your chimney to the outside since it created compression in your exhaust and and is counter productive to your flow! That way starting a range exhaust fan can easily reverse you flow to inside your house or your garage. In the case of a garage letting the door open could also cause the flow to reverse.
Would a hopper with wood chips help the fueling side of this project? That if your so inclined is even something you could automate say... One of those timed release kibble setups for dogs but that feeds wood chips into your burner.
I have been told if the chimney doesn't burn hot enough you get creosote build up, if I understand that right then do you have build up and what do you do about it
Hmmmm I may have to build that. As far as making sticks small enough to fit in there. Get a 14" bandsaw, and decide on the dimensions and start cutting. I probably already have 2 or 3 buckets of pen blanks that would fit right in there. One suggestion I would have is to add a small computer fan on the exhaust as well to ensure you get it going......
Congrats, you just invented an inter-cooled, super charged wood stove. This is quite possibly the most over-engineered wood stove in history in the best way possible
THANK YOU!!! So wanted this since I first saw it after subscribing.
Love the channel! Keep up the awesome work. 👍🏼
This is sooooooooooiooooo awesome
the hippies typically say you cannot make your combustion chamber out of steel, but i believe that's only true for the larger systems, like ones with 8" cross sectional flow area. the temperatures in those are much higher, and the steel will rust out within a few hours of running
I was concerned about creosote build up in the heat exchanger but I see in another comment that you have pulled it apart and haven't seen that to be an issue. Makes me wonder why I have to clean my chimney twice a year when it's a straight shot up.
Hey, hippie here. If you have a predominant wind direction you should point the open end of you intake towards it, and the exhaust outlet away from the wind to generate a flow. If you want to get serious about harnessing that power also, you could stick a funnel on the intake side, and build a little venturi system on the outlet. That would negate the need for a computer fan, and possibly oversupply your stove with air (computer fan is a genius idea btw. I've heard that some fossil fuel based electricity generating stations preheat their intake air by drawing it down around the exhaust chimney, which results in such an efficient heat transfer that they then have to use fans to push the cold exhaust air out of the chimney. Similar to what you're doing here. Good Job)
One thing you did not mention is carbon build up in the heat exchanger and the exhaust pipe. Because the piping following the burning chamber is so cold the residue carbon will condense before it can burn. These build ups, once big enough can burn off and turn your exhaust red hot, so either clean it sometimes or be aware of a possible run-away.
Could'nt you use a heat transfer to create electricity to operate your fan from the top of your heater , then run it to a fan to blow air in it ?
Any cresote problems? It would be impossible to clean the pipes.
Oh yes…we’ve had all kinds of trouble getting the old chimney to draw. Not even making the firebox smaller, could help it draw. Not even sticking a fireplace insert into there helped-it was a disaster.
That’s another reason we bot a Liberator rocket stove + a chimney sleeve, besides how beautifully efficient these are.
I used a drier vent to bring air into the air intake on it…& had to put a damper in that, to adjust air flow in.
But maybe I’ll try insulating the intake, too…had no idea cold air would help the burn!?
When installing the sleeve, I had to remove the recommended insulation wrapped around the sleeve, to fit it up thru the chimney, & simple-stuff it around the sleeve at top & bottom of chimney.
Your cold air intake going direct into your feed tube, seems inconvenient….if it went into the side to of the feed tube, you could leave it connected, & be able to add wood more easily.
Could even use a 4” pipe section to extend the feed tube then, allowing more sticks to be put into it, so you didn’t need to keep adding fuel so often.
Add a rotating chimney exhaust tip that the wind turns like a weather vane to prevent downdraft. If made correctly you could use venturi effect to create draft when the wind is blowing.
You should modify or fasten something to your intake chimney to block the wind from causing the Bernoulli principle backward flow
When you said you were going to do your outtake in front of the stove, but wouldn't because you felt like you were going to be burnt. Just had an idea, maybe put a cage around the helium tank to prevent anything falling on the tank? Air/heat could still go through, but would stop anything from falling on it and catching fire.
50 gallon drums.... not 500 gallon (oh them Hippies). LOL. Dude, this is just straight-up beautiful and just what I was looking for.
Great! But how do you clean the ash?
I would recommend double wall pellet stove pipe because it has a stainless steel liner in it. It comes in 3 and 4 inch sizes. Also 6” triple wall stove pipe could be very useful here. but, good job looks good!
If you could have... Would you have made the intake longer so you would be able to load more fuel at a time??? I am thinking you would also be able to have bigger intervals before you had to add fuel..?
What about a windvain aimed exhaust tube that will create a negative pressure when the air passes around the tube. No power needed.
You could probably use peltier effect plate to run your PC fan once it gets warmer enough so that the system is keeping itself going instead of puling power from the wall
Just run if off rechargeable batteries and re-charge the batteries with your TEG.
Could you put a Peltier semiconductor to run the fan?
you should reweld the handle turned 90° cause than it indicates correct, if the valve ist open oder closed.
In case of power outage you should experiment with peltier wrapped around the cold air intact to power your fan
I don't know much about TEGs, but that fan is so low power that an old car battery would probably drive it for a week or more of use.
Yeeaaaaasssssssss. Been waiting for this.
For a while it didn't sound like the furnace was vented to the outside. Was worried about Carbon monoxide poisoning.
But you don't want the exhaust temperature too low. You want the exhaust to be hot enough to rise up and out.
Get a CO monitor.
What's the difference between forcing cold air up, and forcing hot air down?
How much cooler could the hot air be once it gets to the down tube? I can't imagine it would be significant, it's 6 inches from the to of the heat exchanger.
curious how do you clean out the ash? do you have a trap?
I have just built a new barn and intend on using a rocket mass heater, so I have a couple questions. Well more than that, but I’ll limit myself. Have you ever thought about reversing the air flow in the summer to cool the mass? I guess in your case you would not have to reverse the air flow. What I am saying is force the cool night air through the mass to cool it. Then the warmer air in the room would go into the cooler mass in the day time and cool the room. The second thought I have is an odd fuel. I live on the North American plains and we have an abundance of rag weed ( tumble weeds) which are flammable. I am going to harvest them while they are green and bundle them up tight so they will fit in the rocket. I am not sure what to expect . Do you think I am chasing my tail?
Did you have a high wind cap for your exhaust. If you use a high wind cap, it would help even more
You could take the head off a lawnmower engine and bolt a small wedge to the piston. Then make a jig to hold 6 or 8” blocks to be split. Drive the engine with an electric motor and split very fast.
Would insulating the drop pipe from the rockets tank into the mass reduce the amount of instant radiant from that amount of surface area and put it into the mass possibly helping the draft a little in the process. The surface area of the drop pipe could be 1/5th of the surface of the tank itself (not going to take time to do that math). Maybe a header wrap or the fiberglass stuff you used on the primary burn chimney and leave the joints exposed so you can still remove it easily. Although I think your new outlet chimney can change the issues you had. I would love to see it work without the 12volt fan except for start up times. Also dollar store aluminum tape can hold up to 700F I use it on my woodstove outlet flue joints before the masonry chimney and the joining of the flue to the stove since everyone's 8 inches isn't exactly the same (0.o) and I didn't want to build a shim. I take this off twice a burn season at the stove to clean things and have seen it peak to 700F when I fire it off sometimes before I engage the bypass to the cat chamber and all is well with it. I know what you mean by scavenging all the heat my stove full burn the box is +-500F with the cat up to temp 1200-1400F my flue temps drop to 250F versus 500+ with the bypass open at full burn. 700lbs of cast iron and tossed some old chevy heads on it for good measure. I might not be as efficient with the wood but for a woodstove I think that is pretty good being my flue temp gauge is only 3 linear feet from a 1400 degree cat the design makes use of expansion just after the cat there is a chamber before the flue this somehow lets a majority of that 1400F radiate through the walls and top plate and only put 250F up the flue that is internal smoke path temp not wall of flue temp. Since I have an outdoor masonry chimney I wouldn't want any less than 250F going out.
If you added a pellet feed, where would you patch it in?
great video .. excellent theory and practical demo . first time I have seen a sort of torroidal burn chamber fabrication . I have my torroidal vortex design laying horizontal where it leaves the burn chamber the riser exits the centre of the donut shaped refractory cast torroidal secondary burn zone .
My understanding is that you want the burn chamber itself to lose heat fairly freely, and not get super-hot, so that the insulated riser, of refractory brick/concrete/metal where the refractory temperatures are achieved.
Awesome! But how do you get rid of the ash? I can imagine it makes a lot of ash in the nautilus, when you burn white printing paper in it.
Edit, typo.
I guess all the ash gets blown away by the fan. And he has a cleaning port at the base of his heat exchanger where it would accumulate.
thats what i wonder
Far out, man. This is so groovy. Keep on trucking. Peace.
I love how angry you get at the hippies every time you talk about this system, haha
Declaring war on hippies is only the right thing to do.
Them damn hippies, put some shoes on and learn some real science
Yeah...Those damn hippies and their smarty pants awesome and cheap heating idea that this guy hasn't been able to figure out but is certain that his occasionally failing attempt to duplicate it is better. LOL
Hey... easy... this hippie is a techno-geek... welder/craftsman/machinist/carpenter/engineer, who understands thermodynamics, amongst many other subjects... including psychology...
Peace
Jairus is obviously always the smartest guy in the room.
Man, I would love an update on your heater to know how it's holding up and if the steel held up or not. Or just an update in general, you haven't posted in a long time
what about adding some sort of hopper to feed fuel?
The comparison with propane at the end is a little misleading. It sounds like you're suggesting the rocket mass heater is more efficient than the propane heater because the rocket mass heater keeps the room warmer longer. But that's a question of convenience, not of efficiency. After all, you could create a propane mass heater if you wanted, and that would keep the room warm for a long time, too.
Please add this one to the playlist!
Please
I'm going back to watch the series. So, ignore this post if you address the question. How would this compare to a normal wood burning stove?
Could this be scaled up for 2500’ house?
I hate to tell you this, but, I think we’re on the same wavelength.
That being said, I’m old and had trouble keeping up with you. Is there any way I could get a semi-detailed drawing? You’ve done a great job. Thanks 👏🏻👏🏻
I love how you talk about the hippies.