Rocket Mass Heater Cast Core Plans

[mannytheseacow]

Hi WF. I apologize, I haven't been on the boards for ages, so I don't really know your application, but I think the best way to think about these heaters is much like any other heater. You want to keep a minimum path between combustion and exhaust to ensure efficient operation. Once this is accounted for there is almost endless scenerios for how to extract heat off of it. You can make your "zones" or "loops" quite extensive as long as you afford yourself the option of switching back to a short path when needed.

To simplify, run two T's straight between the combustion and the exhaust with a damper between the Ts. From those Ts do whatever you want. You can open the damper to preheat the output chimney and then close the damper to extract heat through your loop. I'm sure there is a scientific calculation to figure out how to complicate the system and match a length of pipe to a stove diameter, but the aforementioned approached makes the most sense to me.

[wfwarner]

this is my first time to post a picture so bare with me if it is a mess. finished pouring it and will fire it up soon. the piece attached to form with screw is a blockout for glass window so I will post another photo when I put the glass in. I am going to just let it burn out with my first burn.

[pdk17]

Thanks for sharing. I'll be following this build. I thinks it deserves a thread on its own.
Cheers!
Piet

[wfwarner]

[img][/img]
firing this one up tomorrow.

[mannytheseacow]

So good to finally see some photos! The mix looks very wet; any cracking problems?

[wfwarner]

raining today so I might not get to fire it up. the first one I cast using the same mix only has one small crack. this is a very workable mix with extra type n cement added so cracks will be a minimum.

[wfwarner]

fired it up tonight. all went well

[Oddmar]

Hey wfwarner, did you see my tips n tricks illustration at
viewtopic.php?f=6&t=632 ?

I'm having a problem finding exposed clay locally (currently visiting my mom in Ill-Annoys) and your castable mix sounds interesting.