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Very interesting. Everything I am doing with my Tarm is actually contrary to what is recommended in this article with the exception of the coals in the middle of the slit. I always thought smaller slits were better, thought 15% MC or lower was ideal, and thought it was bad if there were any coals or ash in the gas tunnel. Does anyone disagree with anything in this article?
 
There has been much discussion here about small splits and very dry wood resulting in puffing.
Which can be resolved with larger more moist splits.
 
Im more or less doing what they say. Though I dont measure moisture content. And I bring the wood in for a couple days before I burn it since I dont have it covered very well outside. (bunch of leaky tarps) Works for me.
 
I would tend to agree with the majority of recommendations in the article. MC lower than 20% seems to cause huffing and stopping of gasification. This causes unburned gasses to escape due to lack of oxygen. This also happens with too small splits.

I'm not sure about the raking of coals as I have a different unit than the Profab.
 
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Keep in mind this advice is from a OWB company. Their idea of too small and too dry may be different than someone selling batch-burning boilers designed to be used with storage tanks.
 
First for you to consider. I am a newbie at wood gasification boilers.

Comparing to the article referenced in this post: In my short (3 weeks) experience with an EKO 25, I get a good purple to blue flame in the secondary chamber using the following techniques.

1) Before first fire, the removal of tube cleaning device
2) Chains hanging in the tubes
3) Reroute of wiring for ac power supply and fan (delivered with these cables laying against the water jacket)
The wiring is now behind the 1" rockwool insulation
4) The splits are basically at card size and under (mostly less than)
5) Moisture readings of the oak, maple, cherry and poplar are between 18 and 22 percent after resplit
6) Primary air set at 7/16" and secondary at 4 turns out
7) Fan speed set at 70%
8) Initial fan opening at about 60%
9) After burn is established the fan opening goes to about 5/8" at outer edge of opening and the bypass is
closed
10) Check for gasification and walk away
11) If necessary to load additional fuel, draw coals over secondary opening and add splits
12) Check for gasification and walk away

The only difference to the article that I see is split size. I will definitely try larger splits mixed in and see how that goes. I use the weight of wood in relation to water weight, temperature rise needed for the volume of the system. So far this has been an accurate method, I use 5350 btu per pound of wood in the calculations. I am aware that each boiler operator will have their opinion based on actual btu per pound in relation to actual boiler output. I began using 5000 btu per pound and worked it up to 5350 using the current wood supply and found this to be the relative actual output of this system. If the larger split theory proves out, it would be great to get the btu's per pound up to 6,000.

Does anyone else know what they are getting out of a pound of hardwoods?
 
That article seems to be EXACTLY how my Wood Gun burns best.

Hello avc8130:

About your boiler and its primary chamber. Does the Wood Gun Have a tapered to the nozzle design?

How do you load the firebox with the varied sizes of splits?

Are the large splits over center, off center?
 
Very interesting. Everything I am doing with my Tarm is actually contrary to what is recommended in this article with the exception of the coals in the middle of the slit. I always thought smaller slits were better, thought 15% MC or lower was ideal, and thought it was bad if there were any coals or ash in the gas tunnel. Does anyone disagree with anything in this article?

With my Tram, no problems huffing, and quite frankly load it and forget it. Drier the wood, the better/quicker the storage tank gets heated up. This looks like typical OWB sales pitch. I was waiting for the "bonus" section about adding tires and garbage. They call that free heat?
 
I think the "do's" are just about right on. I differ 1) in splits, as I split typically into 3-6" sizes, with a few larger; 2) I don't check with a moisture meter, as all of my wood has dried at least two full summers with rain cover, and my wood is pine and aspen, quick drying woods; and, 3) I don't rake coals into the lower gasification chamber, but I do scoop out about 1/2 of the ashes in the firebox about once a month, leaving a good ash bed behind.

I will get occasional puffing with extra dry pine, but I usually can limit this by adjusting the damper on the draft fan to provide less air. An occasional puff is of no concern, and there is no blow back of smoke into my shop where I have my Tarm.
 
Hello avc8130:

About your boiler and its primary chamber. Does the Wood Gun Have a tapered to the nozzle design?

How do you load the firebox with the varied sizes of splits?

Are the large splits over center, off center?

The primary chamber is shaped like a "U" with the nozzles at the bottom.

I basically just pile splits/rounds all "North-South".

Generally when it is time for a reload, the nozzles are completely exposed and there are 2 splits charred but still intact...one on each side of the nozzle. Everything else will burn away. I just push these two splits over the nozzle and pile new wood on top.

ac
 
There has been much discussion here about small splits and very dry wood resulting in puffing.
Which can be resolved with larger more moist splits.

Not from the members of my "underground" :)
 
Not from the members of my "underground" :)
Not in ours either. :) the WG is a real mans machine and can handle big splits. No need for those fancy little splits. But I meant out in the open discussions.
 
Not in ours either. :) the WG is a real mans machine and can handle big splits. No need for those fancy little splits. But I meant out in the open discussions.

Oh, I thought you were talking about puffing from small splits. I've never seen that so I was probably confused. My bad.

I bought a wood splitter last week unassembed from TSC that came on a big pallet. I cut out the nails and stuffed all the scrap in the unit for one burn. That was pretty cool. It definitely went against most things in this article.
 
I have been operating my Eympire Elite just as the article says.
All I can say is that the was the advice they gave me before I bought it, and that's the only way I've run it.
It works for their machines, I'm not sure how well it works for other makes other than the Empyres and my buddy's Wood Gun. He uses the same methods and swears by it.
 
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With my Tram, no problems huffing, and quite frankly load it and forget it. Drier the wood, the better/quicker the storage tank gets heated up. This looks like typical OWB sales pitch. I was waiting for the "bonus" section about adding tires and garbage. They call that free heat?

Same here. From my experience dryer is better, smaller splits dry quicker/more completely and I can fit more of them in the fire box (ie less likely need to reload). So pretty much nothing in that pdf seems to apply to me.

K
 
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I think the key is how it is being operated. The pdf and their boilers are for non storage. From talking to them at the plant, they don't want all of the gases being sent out the flue as it re fires, leaving char coal but little gasses to be burnt. except for those little wood gas explosions my buddy used to complain about before loading using this method. I told him that's how it got the name Wood GUN!!;)
 
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This is my 4th season with my EKO 25 and storage,the first 3 years I used small splits and was able to burn a very intense fire for approx. 12 hours before allowing the fire to go out and completely go out ,I was then able to heat my house for the next 36 hours from the storage ,after which time I would need to start a new fire and repeat the whole process. In order to burn this intense fire I would need to use small dry splits as mentioned and need to feed the fire approximately every 2 -3 hours,by using these small splits there was a lot of gas build up which in turn created a lot of puffing,but since the boiler was in a out building that wasn't a huge problem.

This year I took different approach,I took a half of fire brick an put it in the middle of my nozzle so that approx half of the nozzle was blocked,fan speed was also decreased to 50%, I then used small splits only when my coal bed was really low and then only just a few to help re- establish the coal bed with larger pieces on top some times much larger due to the fact I had a lot of wood that was hard to split by hand.some of the larger pieces on top were no always dried to optical conditions but by the time they were towards the coal bed they were plenty dry.

What I was able to accomplish

*I turned my EKO 25 into probably the equivalent of a EKO 10 which was fine because it was still more than sufficient to heat my house,domestic water,while still adding to storage.

* Because I was burning at a slower pace I could get away with feeding the fire every 6 - 10 hours giving me what I feel was more freedom and I only let the fire go completely out maybe 3 times the whole winter ,which I believe also gave me more freedom because I wasn't trying to establish a new coal bed every 48 hours.

*Larger pieces of wood done away with much of the puffing problem.

* My fires were still efficient and gasifying properly with no smoke coming from chimney and always had the storage tank to push against preventing it from going into idle mode.

* I still had the option of using smaller splits in times when the storage was at the lower end of the spectrum.As with driving a car you know from experience when to give it more or less gas(acceleration) to meet your current driving conditions,I had the choice of doing the same with the boiler to meet my current weather conditions vs my current heating needs.

This approach may not be right with every one but I felt it to be very beneficial for myself.
 
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This is my 4th season with my EKO 25 and storage,the first 3 years I used small splits and was able to burn a very intense fire for approx. 12 hours before allowing the fire to go out and completely go out ,I was then able to heat my house for the next 36 hours from the storage ,after which time I would need to start a new fire and repeat the whole process. In order to burn this intense fire I would need to use small dry splits as mentioned and need to feed the fire approximately every 2 -3 hours,by using these small splits there was a lot of gas build up which in turn created a lot of puffing,but since the boiler was in a out building that wasn't a huge problem.

This year I took different approach,I took a half of fire brick an put it in the middle of my nozzle so that approx half of the nozzle was blocked,fan speed was also decreased to 50%, I then used small splits only when my coal bed was really low and then only just a few to help re- establish the coal bed with larger pieces on top some times much larger due to the fact I had a lot of wood that was hard to split by hand.some of the larger pieces on top were no always dried to optical conditions but by the time they were towards the coal bed they were plenty dry.

What I was able to accomplish

*I turned my EKO 25 into probably the equivalent of a EKO 10 which was fine because it was still more than sufficient to heat my house,domestic water,while still adding to storage.

* Because I was burning at a slower pace I could get away with feeding the fire every 6 - 10 hours giving me what I feel was more freedom and I only let the fire go completely out maybe 3 times the whole winter ,which I believe also gave me more freedom because I wasn't trying to establish a new coal bed every 48 hours.

*Larger pieces of wood done away with much of the puffing problem.

* My fires were still efficient and gasifying properly with no smoke coming from chimney and always had the storage tank to push against preventing it from going into idle mode.

* I still had the option of using smaller splits in times when the storage was at the lower end of the spectrum.As with driving a car you know from experience when to give it more or less gas(acceleration) to meet your current driving conditions,I had the choice of doing the same with the boiler to meet my current weather conditions vs my current heating needs.

This approach may not be right with every one but I felt it to be very beneficial for myself.

I do something similar with my EKO 40 with similar results. I call it "Seasonally adjusted nozzle modulation"
Nice to not have to restart a fire every time.
I know ,it don't take long to start,but still. As the season drags on a person loses interest.
 
"Seasonally adjusted nozzle modulation" that's a great description mr.fixit.

Knowing what I know now it probably would have been advantageous for me to go with the EKO 40.it has the same footprint of the EKO 25 but is taller allowing a larger wood load and longer boiler tubes.Who knows how much longer between loads I could have went.
 
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