Home Made Boiler up&working; [Can Secondary be to Hot?]

[ozzie88]

Hello People,been a while but have photo of my boilor working. Took me 4 different times adjusting the air flows in both chambers but think I have it? Takes about 25 minets to get to gasification then around 2.3 hours to heat 170 gal. to 190* With the outside temp. here been upper 30s and 40s this will last me 3 days.
But the second chamber gets very red hot,the firebrick and panels glow bright red, I can adjust air to get yellow to purpel to blue flames, can this hurt the boiler?
It holds 18inch long wood and the box is only 12 wide and 15inch. tall and 18 long, but one load seems to do it sometime have to add a half load if she takeing shower and did dishs while heating up,[takes long hot showers too]
When it is running hot I can add like damp cedar or hemlock and it burns it right up,I start it with dry hardwood.

 

[Duetech]

I don't know what the "panels" are. If you mean metal then you need to get the metal protected or it will warp. Gasification can readily produce 2k deg + and stell will warp at those temps. Would like to see something of your design though as I am contemplating building one of my own.

Check "tuning your EKO" to get some information on the flame color and what it means. Basically yellow is not tuned as well as could be but will still turn things red hot. Blue is really clean burning and very hot. White is too much oxygen and probably too hot. Thanks for posting!

 

[ozzie88]

Hello, The panels you see glowing red are Cordienite 5/8 thick suppose to be rated at 2,400*, the sides are 2 1/2inch firebrick they to get red hot.
I have an older post I put on few months ago with photos of my creation, I did alot of reserch on sizeing and air, all welding I did with e-7018 and 6013, seems ok so far,

 

[Duetech]

From posts a couple of years old ash supposedly hardens or melts at around 2300f (not an expert here so I am just quoting what I have read). Just to be on the safe side and since your emissions are clear I think you should experiment with reducing your secondary temps to reduce the glow of your cordienite but not eliminate it (even commercial gasifiers often have secondary chambers that glow). Just for information and effect if you have a small piece of firebrick that you can put in the secondary chamber and directly in the path of the flame perhaps you can gauge the actual temp by the effect of the flame on the firebrick. Nofossil has experimented with different refractory combinations/materials with his EKO25 and what he has learned might be helpful to you so you might try a search of his posts circa 2009 plus or minus a few months. I don't believe you want to stress your boiler and shorten the life of it but I also believe you don't want to throw out energy no matter how clean it seems your exhaust is. Last but not least is evidential deterioration of your refractory components. So watch for signs of erosion and or crumbling as they are signs of excessive turbulence or heat. Congrats on the build!

 

[ozzie88]

Hi, I want to say thanks alot for your answer and info, this helps alot, I have learned alot on this site about these boilers and would like to pass on what I have learned while building this thing, I live up here north maine in woods not to many people around so all info is a plus. I will try what you suggested and post again later. I just never thought it could be so hot, While it is runing the water comeing out of boiler is 15* hotter than water going in, so I think this is ok and heats evenly ?? Water jacket around the bottom and sides of top is 1 1/2 inch. thick with 5/16 plate, seems to be enough so far? Like you said I dont want to do any damage to it but get best heat I can.
In this photo you can see the 4inch. pipe comeing from top to blower for pre-heat outside air,from blower air goes to 3 other 1 1/2 inch pipes to chambers. and the bottom chamber is the green door and the 2 pipes sticking out just above are the secondary and 3rd. I guess being right under the top tank and tubes. That what the other photo is looking threw one of the pipes. The storage tanks are all insulated now.