Steve C. :welcome to Permies.com, our sister Site Richsoil.com, and a Big Welcome to the Rocket,
Wood stoves, and
Cob Forum threads
Location Location, Location: If possible we wan t to connect you with a Fellow Member and Rocketeer who is a Near Neighbor With
RMH,
and Cob
experience, and a little Aquaponic Experience would
be nice !
Look at Your Name space to the left of your 1st post and L@@K at mine ! Below are a couple of handy links :
https://permies.com/t/34193/tnk/permies-works-links-threads (adding location)
https://permies.com/t/43625/introductions/Universal
Lets follow the Flow of your Fire and Combustion Gases as they flow sideways down the length of your Burn Tunnel, and then flow
up into your Heat Riser As these Gases struck the underside of your Barrel they mix in a toroid or doughnut shape completing Combustion.
The Hot Exhaust gases radiate heat out through the wall of your Barrel and it is at this point the now cooler exhaust gases Fall vertically
down the outside of the Heat Riser And inside of the Barrel
To respond to your question :
Will the downward turn hurt the air draw, etc.
This is where we find the Downturn -at the top of the barrel- The point where the Exhaust gases falling vertically then turn 90º to flow
horizontally through Your RMHs Thermal Mass is adjustable to fit your Specific needs !
Things to be considered The horizontal ductwork
should run through the center of your Thermal mass to ensure even/equal heat
distribution Even with most of the Thermal Mass located within the ground?Below ground level if the Mass of Rock and Cob above the
horizontal piping is not just as thick you will radiate more heat and at a higher temperature from the thinner Side !
Usually we build our thermal mass as a bench or bed like structure when it is placed within a home ! When placing it in a
Greenhouse
we have some special considerations! You can and should plan your RMHs Thermal bench to be at or above a working height, This
saves backs (Your back ) and allows you the option of using the floor as a cold sink and keeping tender fish and Plants above the
hardest area to heat !
At that point where your vertically falling Hot Exhaust gases turn at Right angles to flow Horizontally you will want to position your
first clean out, Usually one of Three. You will definitely need to plan on a second one at the point your Final Vertical chimney leaves
Your thermal Mass and Exits through the Roof of out at a sidewall on the down wind or Lee side of your Greenhouse !
While a Cleanout can be flush mounted to the top of your Thermal mass connecting vertically down into your Thermal Mass's
horizontal ductwork, your plans to set a large fish tank above your Thermal Mass limits useful placing of these Vertical Clean outs
O.K. a little side trip : Please use a great deal of caution when researching existing builds, particularly when Viewing U-Tube Videos
There is a lot of steaming piles of absolute crap out there ! Often some one tries his hand at a D.I.Y. Build, makes a video- places
it on U- Tube and when he runs into problems moves on - chasing the next shinny Bauble and leaving an abandoned U-Tube
Video
behind !
Having said that I am sending you to a U-Tube channel of a fellow member LOTS of Good stuff Try not to get lost !
Link below : Enjoy ! For the Good of the Crafts ! Big AL
https://www.youtube.com/user/web4deb/playlists