Backyard Aquaponics
A place to discuss aquaponics

Hi Guys
Been wanting to build a Rocket Mass Heater to heat my greenhouse and finally came up with a plan.

Have been doing some reading and came up with a design that fits into my green house, but since some people have built RMH's and made the mistakes, I thought it would be smart to post my plans (Basic) here to allow any design issues to be ironed out first. I also posted it on permies and will update any issues with the idea.

the major differences are;

I wanted to move away from using the 44 gallon barrel. I'm not quite sure if this is allowed? (I can re integrate it in but just wanted something safe to touch incase my kids get in there. )
As I understand it, the barrel assists in the cooling of the gases helping the draft pull the gasses down. Will my design work without the barrel.

Here are some images.

Looking forward to this one Matty

Update time,

well version 2 has been put together mainly to test the different types of brick as the paver type did not late long. any how here is the video.

regards

Matt

Well there has been quite a bit of tinkering going on in regards to my original RMH plans.

About a week ago I temporarily built the RMH with the brick stack(riser) coming from the burn tunnel then back down to the common header. this proved not to work very well and did not draft much.
I think this was for a couple of reasons.
1. the riser leaked like a sieve.
2. the riser was not insulated.
3. the flue gases need to be cooled to assist in the drafting effect.


So after some more reading I found that I would have to return to the 44 gallon drum design.
Basically, I moved to a more traditional riser (insulated 6 inch) which I insulated with and 8 inch gal pipe with basic roof insulation, and temporarily sealed with mud. Also I added the 44 gallon drum to assist in the rapid cooling effect to the combustion gases which assisted in the draft for the RMH.

The results were pleasing. Now I'm planning to seal some 6 inch flue into the lower section to insure that it still drafts.

Here's some pic's and a video. (recorded on mobile phone).

regards,

Matt

Watching with interest, mate.

Ditto.

Well I found some time to seal the 6 inch flue pipe into the bottom of the brick work and fire it up.

Awesome, worked a treat. now its just a matter of fitting into the hot house.

here's a video...

(Sorry Youtube says that its going to take 2 hours ) going to bed check out the video tomorrow..

regards


Matt....

So mattyry, do you actually need the whole heater inside the hot house or can you just duct the flue through the wall of the structure. Also does the flue need to be flue to atmosphere or can it terminate inside the hot house with say a vent to let out excessive heat and gasses.

in regards to having the rmh being in side or out. you can do either, but i‘ll install mine inside as it will add to the amount of mass and insure that not much heat is wasted.
in regards to where the flue gasses are dispersed. all solid fuel fire processes when runnimg produce carbon monoxide, if not runnimg well it can produce lethal amounts. (= very bad for humans.) you can not smell it or detect it at all. so i will be running my flue through the mass and outside. I‘m hoping that i can recover most of the heat before it leaves the hothouse

regards

matt

I really enjoy how you just get stuck into things and make them happen mate. If any of your previous adventures are something to go by... well I call this success before you even begin. You really kick weather in the face with your designs and outcomes. Well done.

thanks for the incouraging words Charile, I
hope now that I can live up to the expectation.

This looks fantastic, and truly inspirational! I knew rocket stoves were meant to be efficient, but seeing the truly smokless output in your video is something else.

Have you tried it with more ducting on the end? do you think that will restrict the flow at all, reducing efficiency?

I'm thinking of trying something similar (6" flue pipe insulated by 8" galv pipe), but using 12" galv pipe instead of the 24" barrel, to save on space and help stop rusting. This would give me a 2" clearance all around the 8" outer wall of the riser. Do you think this would work?

How hot does the lid of your barrel get? It look like you're boiling a kettle on it, so I'm guessing pretty hot I'm thinking a galvanised end cap would not last long against that heat.

Awesome mattyry

In regards to how hot the top of the barrel gets, it get bloody hot. at night time you can see the top of the barrel glow.
In regards to the smaller barrel or pipe over the riser tube, this part of the system is pretty important as it help transfer heat, assist in cooling the flue gases so that it assists in the drafting effect. so by putting a barrel on top that has a smaller surface area will reduce the heat exchange and thus reduce this effect. But otherwise, you could give it a shot and see if it still drafts.
No I haven't tried it with more flue yet, but i'm pretty happy with its performance at the moment. just got to wait till I get some more coin to finance the rest of the flue.

regards

Matt

Here's a quick video of the RMH heating water.
It was put together pretty rough as a friend wanted to know if water could be heated up as well.
any how i rolled about 25m of half inch copper and mounted it around the outside of the rise.

It worked surprising well. I was hoping it would thermo siphon but all it did was boil, so i placed a small pump inline to circulate the water. It heated about 30 liters of water to 58 degrees in 12 mins.
any how heres some pictures and a vid...