help! why does my rs smoke?

Good morning all the permies
I'm constructing a fantastic heavy duty rocket stove - confidently convincing everyone here that I'm building a wonderful machine that you could on, in the house, with no chimney - because it doesn't smoke. It was a little embarassing when we tedted it last night and... IT SMOKES!!!
I used a metal drum, stainless steel tube, and expansive clay for insulation and sheet metal plate as a lid. It draws well, but definately smokes.
Am I wrong in thinking that it could be used indoors without a chimney? - I thought this was the whole intention of the clever design.
Or did I screw up somewhere?
We used some fairly rotten fig branches upto 5cm diameter.
HELP! HELP! HELP!

Ciao Eko.


Ha fatto una cazzata!

Yep you screwed up. They don't smoke much, but they do smoke a smidge. What is your rocket for? Cooking or heating?


If for cooking, look at aprovecho "institutional stove" for inspiration.

And if for heating, go buy the book!

Amount of smoke is directly related to how hot the fire gets. I forget the numbers off the top of my head, but it seems like I have 1400 F stuck in my mind as burning a significant portion of the smoke and other gases. By the time that temperature approaches 2000 F you may expect most of the smoke and gases to burn up (and I think somewhat lower, like 1800 F, but verify that as I am not looking at my notes and I'm just ball parking (approximating) these numbers).

Chimney or no chimney is a little different matter. Depends upon draft, exhaust temperature, wind direction, and local variables of how your building it put together, what is in the immediate area, etc. My rocket heater requires a chimney. I suspect that most do. All of them vent to the outdoors. The question is where and at what height.

Thanks for the replies,
The stove is for cooking indoors.
They might want to use it for heating as well. I'll have a look at the "institutional stove".
I also have to look up F - °C convertions.

It doesn't smoke THAT much - but certainly too much for indoors without a chimney.

So, it might indeed be that the chunks of rotten wood did not burn hot enough?

Am I wrong in thinking that it could be used indoors without a chimney? - I thought this was the whole intention of the clever design.

I'm confused about the use of the word 'chimney' and 'vent'. Do you mean that you have no chimney rising outdoors from an out the wall vent? or no vent to the outdoors at all and the smoke is coming into the room from an unvented rocket stove?
I think everyone here has assumed that your stove is vented to the outdoors and you are just lacking a chimney
My only experience is with a conventional wood stove that will smoke back into the room if the chimney isn't high enough.

it is very very dangerous !!!

So yours is definely a rocket stove for cooking, as opposed to a rocket mass heater which is a heating device. Sorry to disappoint you, but cooking inside the house with doors and windows closed is not the way to use this thing. It will emit some smoke one way or the other, especially when fed with second class fuel like damp wood. When cooking indoors is your goal it would be best to look what an institutional stove looks like. The downside of such a device is the fact that it is built around a dedicated pot which will get black on the outside. Great for soup, stew or food like that.

I've built a couple of those years ago, scaled down to a 10 liter pot. Please see this link.

And this link!



https://www.youtube.com/watch?v=VdhLWMW7IXA&list=PL4F97B69F2748D32A

I understood that the basic rocket stove was designed for people in ' third world countries'
where we cook indoors on open fires which cause the associated illnesses - a very economic stove that causes little if any smoke.
Have I got it all wrong???
Thanks for the replies

eko aksie wrote:I understood that the basic rocket stove was designed for people in ' third world countries'
where we cook indoors on open fires which cause the associated illnesses - a very economic stove that causes little if any smoke.
Have I got it all wrong???
Thanks for the replies

Are you saying that you understood that these stoves were unvented to the out side and that the one that you built is not vented to the out side either?

The original rocket stove gives far less smoke than the dirty indoor stoves previously in use, improving health immeasurably in that situation. However, it is not completely smoke-free and in an American type residence would be unacceptable. It needs to be vented outdoors like the institutional models mentioned.

Yes Judith, although it's portable so you could move it outside.

Yes Glenn, I think tjis is probably where the confusion came in! Tjanks for ypur reply