Michael Brix

Greetings from cold Denmark

I'm just about to build my rocket mass heater. Would you guys let me know from a more experienced builder, if you think this will be a pretty good build - please help.

Here's a link of my plan:
https://drive.google.com/file/d/0BwnOTepq0QVqR1cwNkc1emh0cGhvZ2h0U2JOQjFRVFF0Mko4/view?usp=sharing

The whole system is 8" - the end chimney is a 12" and is 21feet tall indoor isokern.
The burn tunnel is close to 25" from end to end. And heat riser is close to 51".

The ducting is close to 18 feet.

Think this is a pretty good build that will probably work?

Hope you'll give me your thoughts on this.

Sincerely
Michael

Thanks for the help.

For someone else facing the same problem as me, i can confirm having talked to two other separate RMH-owners that have the same dimensions mentioned and have it running smoothly.. So these dimensions are certainly easily able to function very nicely together.

Phew - just working trial and error buying a 1000$ chimney is expensive erroring... I was hoping i could get close to buying a chimney that will PROBABLY work...
Im making by the way a regular oil drum and using high quality fire bricks (lightweight kind). Insulation with perlite... Engine part will burn well i'm sure... Just much in doubt about the chimney... I was hoping some people could at least advise me on which size they would buy if they were making a system like mine...

Thank you so much for taking time to explain this so thoroughly... i think i'm understanding the mechanisms... but so... If i make an 8inch system - 6 meters of exhaust tubing inside of the mass - 3 meters forward to an elbow going 3 meters back and up the chimney.... Do you guys THINK a 12 inch chimney (indoor isokern of 9 meters tall). will be a good idea here? - or should i work harder or pay more to try and find a 8 inch chimney?

So if i'm reading this correctly the 30cm chimney will be too wide for a 20cm system right? The chimney will be close to 8m. tall to rise to 1m above roof top.

Would you mix perlite into sand and cement - or just clay and perlite to insulate the heat riser and burn tunnel?

Hi Guys

I'm making this 8inch RMH, but have difficulty finding af matching chimney. I have found a cheap one that is 12 inches inside.... Will that be super, or is it a problem with too much draw there? I would think it would be super, but would love to be confirmed...

Another thing... can anyone guide me to a good guide to make the combustion part out of standard firebricks (heavy type pizzaoven)... I'm really having a hard time putting them together in a smart way, so i get the ash-collector etc... Would loove to see how this puzzle is made smart... I just want it simple.... for the simplicity of it as im building myself and noone else to spare with.

Hope you will help me out.

Thanks

Michael

Hi Satamax Antone

Thanks - those leca pellets are molded into concrete made into stones. These: http://www.fc-beton.dk/lecablokke-600-10x19x49_114r78.html

Not very much insulating these stones, but thought it won't be totally wasted in the concrete mass below... I don't know what else to put under this big mass - insulating yet strong...

Thanks Glenn

I have the book and have read it ... reading again right now. I just get nervous and want to make sure i don't make a brainfart, since i'm building it all alone.... nobody to catch them
Ok - i thought it needed to be even taller than wide. But almost the same i see... It's big compared to the 6inch test build i made earlier. These dimensions do not make it quite as easy with my fire bricks...
So this big heat riser will take a bit off the insulation around it between the oil drum and the heat riser... will this be fine still?
Thanks for your advise.

Michael

Hi great people!

Thanks for a super great forum/website - and for letting me in.
I have read and seen a lot of info here and elsewhere on the net. Now i'm finally building my RMH and am hoping to get some help here. Hope you can help me get started by commenting on these couple of questions:

1: Can someone tell me a good hight and width for my burn tunnel in a 8 inch system?

2: I have made a foundation of concrete on the sand below my house. On this i'm planning to put a 4inch leca stone as a layer on top of the concrete to insulate the mass from the concrete. Is that sufficient isolation there?
Building the heat extraction tunnel of regular old used bricks. Do i need further insulation under this tunnel, or can the bottoms brick be on the leca stone?
I'm buying a vermiculite board to put under the combustion part between leca stone and firebricks.

Hope you can help me solve this out.

Thanks
Michael, Denmark