Oh masters of the blue flame

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Grovenburg

Member
Dec 9, 2011
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After a month of work I have my newly installed Econoburn 100 up and running. It seems to work well but.... I can't see a "flame". My wood is so dry it will light with a match. When I open the bottom door all I see is sparks and such coming out of the top chamber. Should I be seeing a blue flame?
 
Did you get a coal bed going with kindling?

Do you have smoke from stack?

Can you hear a rumbling?

Once you have an established coal bed you should hear a rumble. I never open my lower door with fan running but I switch the fan off and open the door the flame will continue for a short time.

gg
 
I can only speak for me & my unit - I've never seen any other gassifier in operation except a Wood Gun a few years ago.

Mine takes a little while to get the refractory chamber & chimney all up to temps - so it's all yellow starting out then the blue creeps in as the heat builds. If I reload onto coals, I get instant blue. But there's always a flame of some varying shade of colour.
 
Did you get a coal bed going with kindling?

Do you have smoke from stack?

Can you hear a rumbling?

Once you have an established coal bed you should hear a rumble. I never open my lower door with fan running but I switch the fan off and open the door the flame will continue for a short time.

gg


I start with lots of kindling and get a coal bed going. It does smoke from the stack until it gets down to almost all coals. I've never heard a rumbling.


I bought this stove used. It's a 2008 model that ran for two seasons before I got it. How does the "nozzle" work and how do I tell if mine is ok? In the bottom chamber I have one piece of a slate like material in the middle. This is the refractory? Thanks.
 
I can only speak for me & my unit - I've never seen any other gassifier in operation except a Wood Gun a few years ago.

Mine takes a little while to get the refractory chamber & chimney all up to temps - so it's all yellow starting out then the blue creeps in as the heat builds. If I reload onto coals, I get instant blue. But there's always a flame of some varying shade of colour.

Mine is just smoke and sparks / coals coming out the bottom.
 
I don't think smoke is good. Is smoke coming out of your chimney? My chimney smokes some on cold startup (when the flames are full yellow down below), but the smoke soon stops. Do you have a rumble? Maybe you need to adjust air settings? Sorry I have no Econoburn knowledge or experience.
 
Just some thoughts-

have you checked to make sure you have good secondary air available to the nozzle? Maybe something is a bit clogged up.

also, is your lower chamber staying clean with just fine light grey or brown ash? or is it getting sooty? and the HX tubes?

Noah
 
Lots of different experiences. For me initially a flame, mostly orange, and as the tunnel refractory heats up this will change to a roar of mostly an orange gas-like fireball, with sparks. This would typify about the first 1/3-1/2 of the burn of the wood load. Somewhere around that time the "flame" starts to turns to orange-blue and then blue, with a constant roar. As the wood load turns to mostly charcoal-like material, even the blue disappears and all I hear is a roar, with sparks, and essentially no color at all. Both CO and H combust with a colorless "flame," so I would conclude that the later part of the burn is combusting mostly pure carbon to CO and CO2 and H to H2O. Chemists may have a more accurate description. I can't say that I ever see any smoke in the refractory tunnel area, although in the cold start firing I am sure there is some smoke. For a cold start I fire with the bypass damper open until flue temp reaches 350-400F, then close the damper, and what follows is near instant gasification flame into the refractory tunnel and the burn is off to the races.

My Tarm has a round sight window looking into the refractory tunnel and it is easy to see what is going on. If I open the lower door with the fan "on" the sound of the roar and visibility of the fireball is intense. I would guess the extra 2ndary air with the door open changes what is going on in the tunnel area.
 
Just some thoughts-

have you checked to make sure you have good secondary air available to the nozzle? Maybe something is a bit clogged up.

also, is your lower chamber staying clean with just fine light grey or brown ash? or is it getting sooty? and the HX tubes?

Noah


How would I check if I have good secondary air available to a the nozzle? I will check lower chamber this afternoon.
 
How would I check if I have good secondary air available to a the nozzle? I will check lower chamber this afternoon.
The HX tubes are the ones running verticle up the back? I cleaned those with a round brush on a drill. They are perfectly clean.
 
Lots of different experiences. For me initially a flame, mostly orange, and as the tunnel refractory heats up this will change to a roar of mostly an orange gas-like fireball, with sparks. This would typify about the first 1/3-1/2 of the burn of the wood load. Somewhere around that time the "flame" starts to turns to orange-blue and then blue, with a constant roar. As the wood load turns to mostly charcoal-like material, even the blue disappears and all I hear is a roar, with sparks, and essentially no color at all. Both CO and H combust with a colorless "flame," so I would conclude that the later part of the burn is combusting mostly pure carbon to CO and CO2 and H to H2O. Chemists may have a more accurate description. I can't say that I ever see any smoke in the refractory tunnel area, although in the cold start firing I am sure there is some smoke. For a cold start I fire with the bypass damper open until flue temp reaches 350-400F, then close the damper, and what follows is near instant gasification flame into the refractory tunnel and the burn is off to the races.

My Tarm has a round sight window looking into the refractory tunnel and it is easy to see what is going on. If I open the lower door with the fan "on" the sound of the roar and visibility of the fireball is intense. I would guess the extra 2ndary air with the door open changes what is going on in the tunnel area.

I'm starting to think I have a problem with my secondary air.
 
I would guess the extra 2ndary air with the door open changes what is going on in the tunnel area.

I don't want to hyjack this thread because we have to get Grovenburg up and running as soon as possible but perhaps this could be a topic for discussion. My observations of charcoal sitting in the secondary chamber show me that although they are glowing they do not seem to burn away. Could it be that if all the air (both primary and secondary) is depleted in the nozzle the charcoal will not burn away until the fire in the upper chamber starts to burn out allowing oxygen to enter the secondary chamber? Charcoal receipe: Lots of heat ---- no oxygen.

Grovenburg: I suggest trying to get your hands on some firewood that is not from the same batch that you are tapping right now.
 
I'm starting to think I have a problem with my secondary air.

I believe that if you are not maintaining a good fire, there probably is no need for secondary air. There should be plenty of primary air that has not been depleted with little combustion.
 
I don't want to hyjack this thread because we have to get Grovenburg up and running as soon as possible but perhaps this could be a topic for discussion. My observations of charcoal sitting in the secondary chamber show me that although they are glowing they do not seem to burn away. Could it be that if all the air (both primary and secondary) is depleted in the nozzle the charcoal will not burn away until the fire in the upper chamber starts to burn out allowing oxygen to enter the secondary chamber? Charcoal receipe: Lots of heat ---- no oxygen.

Grovenburg: I suggest trying to get your hands on some firewood that is not from the same batch that you are tapping right now.

The wood I'm burning is ash that was killed years ago by the ash boarer. It is so dry it lights within seconds and burns in my fireplace with no hiss. I've also tried other wood from my wood pile, all seasoned for two years, with no different results.
 
With a cold stove how strong should the air jet coming out of the top chamber be with the blower going?

You should just barely be able to feel it.
 
You're closing the bypass damper. Right?
 
I'd try adjusting my secondary air to the extremes for a bit & see how that changes things. That is, open all the way & closed all the way. Your really dry wood might need things to be adjusted one way or the other towards the extreme side. If I think of really dry wood burning in a hurry in the wood chamber, I think either that consumes more oxygen than usual so less will be available to the secondary burn which would require more air there, or that more of the fuel is consumed in the wood chamber than usual so less gasses get to the secondary which would require less air there. Which might then require a coin flip as to which one to try first.

EDIT: do you have a rumble?
 
It's going to be difficult to get good secondary combustion for the first few burns with a new stove or one that's been sitting unused for awhile. New refractory still contains some water, and until that has a chance to boil off completely, it will interfere with your secondary flame. You need to hang in there and have some faith. It's not quite so bad with a stove that's been idle, but they will suck up some moisture, and you need to get it out of there.

The secondary air may need to be adjusted. That's not usually hard to do, but you have to play around with it and observe the cause/effect of the adjustments you make. No point in trying to do it before the stove is broken in, however. In fact, there's every reason not to do it until you've got two or three good burns under your belt.
 
I tend to run my fan speeds/shutters down so far that the flame is not overly visable regardless of color. Like everyone else I do have a lot of orange during startup with higher fan speeds. But once I hit my peak burn I tend to throttle back the air significantly. As a result, on those rare occasions I do open the lower door to peek, I typically have a pretty small visable flame. Some orange, some blue, depends on the day, the type of wood, weather, how I loaded it, how many beers I had while loading it, etc and so on.

As long as my stack temps are normal and my water temps are what I expect I really don't obsess over the color of the flame anymore. One trip through the "fine tuning the EKO" thread should enable 90% of us "non-active controls boiler" users to set it and forget it with regards to primary and secondary air settings.
 
Update. I got home and before I lit a fire i inspected tje refractory. Ive never noticed it before but its wedge shaped. The small end of the wedge was pointed towards the door so i spun it 180 degrees so it was pointed toward the rear. I lit a fire just as before and it started to gassify within 15 minutes. Wow! Could the two be related or just luck?
 
I run mine with small end towards the front.

gg
 
Wouldn't there be something in a manual or somewhere re. the orientation of the refractory? Or call a dealer or the manufacturer to double check?

It could maybe be coincidental in that you did that just as it was getting itself dried out too.
 
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