Econoburn tuning EBW-100

[MikeeH]

I've noticed that I don't always get a nice jet of flame in the lower chamber while burning. Sometimes there is no flame visible and heat output varies. I am thinking that there is too much air flow through the nozzle. The damper on the fan is set fully open from the factory. Do I need to adjust this? Or do I need to adjust the secondary air flow?

Thanks

 

[willworkforwood]

I was expecting one of the EBW-100 owners to post on this one - maybe none of them are active on the Forum right now. So, I'll give you an EBW-150 answer from last year. There is a beefy Sticky about adjusting EKOs, where folks report significant benefits from changes they made. Based on that, I was going to try some stuff on my Econoburn. But then I read a post from another 150 owner. I don't remember who it was, but he made quite a few adjustments, and ended up basically back at the factory settings - he couldn't find an adjustment that seemed to make a big improvement. So I decided not to do anything, and after a couple years of burning, I also feel that the factory settings on my 150 are fine. That being said (and the answer to one part of your question), it's typical to find different efficiencies at various points in the burn. Gassification is probably not going to be great at startup because the good coal bed hasn't built up yet. Once the coal bed forms, that wonderful blue laser shows up. But, during the burn there are probably times when the wood shifts and isn't well placed over the nozzle. A short time later the wood moves back over, and the flame goes solid blue again. I also remember someone saying that looking at the flame with the bottom door cracked open also can change the burning characteristics. However; the 150 has a variable speed fan, while the fan on the 100 is single speed. So, there might be something good that can be done with air adjustments on the 100. But you probably want to wait until someone with hands-on can chip in on this. And if you do anything, be sure to keep careful track of your changes, so that you can back it all out if necessary. And you should also call Dale at the factory - he is a very helpful and knowledgeable guy.

 

[Piker]

I've noticed that I don't always get a nice jet of flame in the lower chamber while burning. Sometimes there is no flame visible and heat output varies. I am thinking that there is too much air flow through the nozzle. The damper on the fan is set fully open from the factory. Do I need to adjust this? Or do I need to adjust the secondary air flow?

Thanks

Anything past two turns out on the secondary air ports on an econoburn will not increase secondary air to the nozzle. You will not likely increase performance by changing either the primary or secondary air settings from their factory positions.

Don't expect to see a torch every single time you open the bottom chamber... near the end of the burn as the wood turns to charcoal, there is much less gas to be burned off, and the secondary torch kind of dies out. A brilliant torch is dependent upon a hot coal bed sitting right on top of the refractory, with dry wood stacked fairly close around the nozzle. Too much air space inside the firebox around the nozzle caused by bridging or gnarly shaped wood will reduce gasification efficiency. Make sure that you keep raking the ash into the lower chamber when you refuel otherwise the ashes will build up between the refractory and the coals.

cheers

 

[pybyr]

I'd tried adjusting the air shutter on the blower on my EBW 150, but I found that, for the overall length of the burn, the original wide-open setting seemed to yield best results over the largest portion of the burn.

 

[jebatty]

Sometimes there is no flame visible and heat output varies.

Usually stack temperature will be a good indicator of the consistency and quality of the burn. I have a digital panel meter with a K-type probe into the stack, which makes it very easy to "see" pretty much exactly what is going on in the gasification chamber.

But, don't always be deceived by no visible flame. During the last 1/3 or so of a burn, when mostly coals remain in the firebox, there may be a very light blue or even no visible flame but the gasification burn may remain intense, best evidenced by a roar when you open the lower door (works for the Tarm). This is the stage of the burn/pyrolysis that primarily is the decomposition of CO and H, the other elements of decomposition having been completed. CO breaks down at about 1100F and H breaks down (into water) starting at about 1400F. There is no visible flame with H decomposition, yet tremendous heat energy still is being released. Of course, during earlier parts of the burn CO and H also are present and being broken down, but decomposition of other elements also is occurring, and it is those other elements which produce the visible flame.

I was quite amazed the first time I saw no flame but heard the roar of the gasification chamber, as if on steroids. A little research provided the answer, as described above.