hi everybody i will be building this 20cm system with two bells above each other,pretty soon and i would like to get some inputs from you .How you can see from the attached pictures,the bottom of the stove is a quite large -ISA 7.5m2 and the second floor bell will have around 3.7m2 ISA. So both of the bells together will have around 11.2m2 ISA which is too much for two bells 20cm system./20cm system =10m2 ISA for one bell, 10m2-15% = 8.5m2 ISA /.So there are 3 smoke flaps to regulate the ISA of the stove and the path of gasses. So the first option, would be to cut of the second floor bell with the smoke flap located under the ceiling of the second bell.In this case the gasses would heat up the whole of the bottom bell/ISA 7.5m2/ but would avoid the top bell/except the ceiling of the top bell. The second option would be to cut off the bench /ISA 3.4m2/ on the first floor, so the gasses would be in contact with the rest of bottom bell/ISA 2.56m2/ and whole second bell /ISA 3.7m2/ together ISA 6.26m2. The third option would be the start up option to cut of most of the bottom bell /except the ceiling/ and whole top bell/except the ceiling/. The first floor part of the stove will be mostly build out of red bricks /except the part above the heat riser/ with dimensions 14.5cm x 30cm x 6.5cm.The top for the bench will be made out of ordinary concrete 10cm thick.Is that ok? The second floor bell will be made out of fire bricks on the narrow side/6.5cm2/,so it can give out the heat faster.There will be a clay plaster over it. So im asking for any input from you, on this design.THX
I have grown up in a two storey house heated from a central place, by air channels. Aside of the room with the tiled stove three rooms at the first floor and four more at the second. It works very well and it is more versatile than any solution with multiple bells. The air channel at each room has a louvre to regulate the flow of warm air.
Post by matthewwalker on Sept 1, 2014 7:44:07 GMT -8
I like it Radek, very ambitious. I would probably try to allow individual damping of both the bells, so they could be brought on line as needed once things were flowing well. I suppose that I'm picturing a start up bypass of some sort as described in option 3, plus a second bell bypass. That all might be a bit complex for the homeowner though.
The concrete should be fine, but will need good reinforcement as I would expect it to develop hairline cracks over time due to the thermal cycling. I have had really good success using it for tops when I incorporate fiberglass mesh (like used in gypsum board/drywall repair) and latex additive. The latex will smell a bit at first but it does add quite a bit of flexibility and strength to the final casting. I have not experimented as much with different thicknesses, but my gut tells me it might be better if it was a bit thinner. Mine are typically 3cm or so thick, which I admit is probably too thin. I have been trying to push the limits there, and have cast some that are holding up well at about 2cm, but that's fairly extreme and is purely to satisfy my curiosity.
thanks Karl but central heating by air chanels its not an option,the owners dosnt want to get dust blown all over the place.And i really havnt seen clean air chanels,all i seen been full of dust and criters in a while.
Matthew ,yes there will be three smoke flaps .By opening the lowest the bench will be cut off.By opening the midle one only 1-4 of the bottom part of the stove will be heated.With the midle smoke flap open and the second bell bypass open the gasses will only heat the top of the bottom bell. The thing with latex and fiberglass mesh sounds interesting,Thx,but ill propubuly stay with 7.5 -10 cm thickness for the top of the bench.I have used once 5cm concrete and it got hot quite fast,and the bench wasnt to high compare to this build.With this stove the top of the bench will be around 70cm above the floor level and the bench it self will be quite large 160 x 150 cm so ill rather stay with something thicker.And there will have to be some pilars inside the bench to suport the top,i guess. s101.photobucket.com/user/snake11112/library/?view=recent
I am not sure if the exposed beam look is what you are going to end up with but I think it goes pretty awesome with the brick. That is a very chick answer but then, hey, I'm a chick. Lol. Keep posting.
i havent been around fast internet for a while ,so here is some progress.I have caped the top of first bell with synthetic cordierit ceramic slabs.I choose those over fire brick slabs because of the weight.There is 10cm/4"/of fire wool insulation and 8cm /3.14"/of rock wool insulation over the cordierit top,i have also added a door in to the "dead"space above the toping of the first bell in order to be able to check on the slabs or have a access to exchange it.The top of the bench been made out of ordinary concrete slabs 8cm thick /3.14"/ with some fire mesh over.Now i will be starting the second bell on the second floor,it will be very narrow and around 1m /3f/high.The whole of the bottom stove is being wrap up in to a juta dipped in to clay slip.More soon.
dan1941300: If possible in metric cm, how many Celsius at the chimney? Is there anything you would do different if building again? Sorry for my bad english, my language is german, austrian. thx a lot
May 11, 2018 9:38:02 GMT -8
smarty: Dan my batchbox reached 1150C so refractory cement rated to at least 1200C
May 21, 2018 22:53:56 GMT -8
mercedes: Not sure where this question will end up...I just registered. HOW THICK SHOULD PERLITE/VERMICULATE/CLAY INSULATION BE BEHIND THE THERMAL BATTERY/COB BENCH IF IT BACKS UP TO A STRAW BALE WALL? Thanks! Can you please also post me: email@example.com thnx!!
May 28, 2018 20:05:23 GMT -8
kkp: Mercedes: Benches don't get real hot. In fact, they are rather cool compared to other areas. You shouldn't need a mix like you described
Jun 7, 2018 18:10:52 GMT -8
maartenmartens: beste Peter, ik heb je eergisteren een mail gestuurd via het contact formulier op je website , heb je die goed ontvangen ? mvg Maarten Martens, architect - geobioloog (mail betreffende de bouw van onze eigen RMH)
Jun 20, 2018 13:21:57 GMT -8
martinm: any one here with info \ experience with heat (from a mass heater) distribution with ducts throughout two storey house ?
Sept 8, 2018 22:58:52 GMT -8
padica: Good morning, this is a wonderful subject, please someone can help me with the theme of double and triple combustion, how it is achieved, theory and design, thank you
Sept 15, 2018 7:13:40 GMT -8
wiscojames: I'm afraid you won't get a response to such a vague question - I suggest reading through some of the threads related to your questions before asking for an explanation. People will be very generous with their knowledge if your question is more specific.
Sept 18, 2018 4:48:00 GMT -8
daniel: in my experience as I am working now on something of that nature, I have thought of making a heat exchanger and distributing the heat through vents using a slower fan. Now after a few years I realize that mass heaters give out primarily radiant heat, for
Nov 30, 2018 12:48:38 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place...
Dec 16, 2018 18:10:49 GMT -8
vesuvius: High Temperature Glass options,
Jan 4, 2019 16:28:17 GMT -8
vesuvius: Do any of you have experience with using the glass from home oven doors on a rocket stove? I'd like to have a viewing port on my stove but don't want to fork out for new ceramic glass. Any thought as to whether it would take the heat of a rocket stove?
Jan 4, 2019 16:30:40 GMT -8
yaya: you dont need the blowair for that temp..
Jan 13, 2019 16:43:57 GMT -8
flybywire: Glass window from an old washing machine is designed to take high temps. Cheap solution to your need.
Jan 27, 2019 0:10:58 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place to have a discussion... it is for short announcements
Feb 7, 2019 0:11:23 GMT -8
coastalrocketeer: you won’t likely get replies to questions here, and it is not a spot that makes holding an ongoing discussion possible...
Feb 7, 2019 0:12:22 GMT -8