valdjiu wrote:
hello,
writing from portugal. we as greece will be kicked out from europe one of these days....
so , e have just made a rocket stove bench with some friends in 2 days.
i was really enthusiastic about it and even convinced my girlfriend that the big monster was going to work fine...
problem is that it smokes back a lot when starting and sometimes after its started, this means that we have to opne all doors and windows.
so... i have build it according the book.
can some one help me?
obrigado ( thank you )
The two things that come to mind are the flue exit from the bottom of the barrel to the bench may not be big enough, think CSA. The other is maybe there is too much air going in. try partly blocking the feed tube with a brick. In the videos I have seen people shaping and reshaping the flue exit from the barrel. I side stepped that by bringing my barrel right down to the bottom and inserting the exit into the side of it (I used a water tank core). I figured that the bottom 1/3 of the exit was blocked and so made sure the space behind the exit inside the barrel is about 3 inches for more than 28sqin CSA of the flue path.
The other thing (which I have no experience with yet) would be flow resistance in the bench... either from corners, too much length or some kind of blockage.
My particular build is covered in this thread:
https://permies.com/permaculture-forums/10653_0/alternative-energy/yet-another-portable-rmh As it is quite different from most cob designs, it may not help in this case... even so the design principles are the same.
