Econoburn 100 good burn, high flue temps low delta and fast burns

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cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
Hello all, looking for some help, the title sums it up, burning to 1500 gal storage, system is totally non pressurized, lets not hang up on that please, I have my reasons at this point, I reciently swapped this in place of my homemade boiler that had developed a leak but other wise worked great, wood is clearly less than perfect but running in the 25% MC area, this thing burns clean, gets a good nice torch, but wont get more than 12 maybe 13 degrees delta across the boiler, flue temps with an internal probe 8 inches out of the boiler collar will run from 400-650+, tubes are clean, circ is a 26-99 on any of the three speeds, true 1" id lines about 17 feet long from boiler to storage. It will burn through a full fire box in an hour to hour and half, doesn't matter what wood, a large amount of fine ash gets to the lower chamber, the thing will blow sparks and ash out the chimney outlet. with the blower running and gassing I have -.02 to -.03 water column for draft. I would sure like some input as to what in the world I have going on here, I would think the way it burns it should charge storage pretty darn fast fast but it takes forever, like 8-10 hours and 6 or seven loads of wood. please help. Thank you
 

3fordasho

Minister of Fire
Jul 20, 2007
1,005
South Central Minnesota
Does your econoburn use turbulators in the exchanger tubes? Flue temps seem high. My Attack that could probably use a tube brushing is seeing around 200C, the probe is right at the flue collar. My other Attack which has only seen a few burns from new is seeing about 160C.
 

maple1

Minister of Fire
Sep 15, 2011
10,821
Nova Scotia
What are your boiler in and out temps?

Storage temps start and end? 1500 gallons is a lot.

Is it new or used?

Tubes clean?

Hopefully an EB owner will be along.
 

airlina

Burning Hunk
Feb 15, 2009
130
western new york
I run the same boiler into 500 gallons of pressurized storage . Sounds like you have a problem with the actual burn. I have thermocouple flue temps in the same place as yours and I would never see such high temps with the damper closed , or sparks out of the chimney as you suggest with yours. Typically at full burn my flue temps top out around 400 deg or so. 350 to 400 deg is good gasification and you will actually hear a low volume rumble when there is no bridging and burning wood is over the gasifier slot in the burn chamber. Also your burn time is way too short. With a fully loaded hardwood chamber i will get 2 1/2-3 hours and to go from my low storage temp at 140 to go to 180-190 end of burn cycle takes 3 to 4 hours depending on house load demand. (remember this is only 500 gals , not 1500 like you have) To be honest , 1500 gallons is a lot of storage to heat with this size boiler and will demand a bunch of tending to keep it fed. That much storage would like a Econoburn 200 or 300 for less maintenance during the heating cycle. In the end I would suspect that your damper door is leaking and you are simply losing all your heat up the chimney without gasification. Call dale at econoburn for advice. Bruce
 

maple1

Minister of Fire
Sep 15, 2011
10,821
Nova Scotia
I have no Econoburn experience but yes, almost sounds akin to a bypass being open at least partly. So most or some of the wood doesnt gasify and what does burn bypasses the heat exchange tubes straight to the chimney. Would account for high pipe temps and short burn time and sparky stuff out the pipe. Sparky stuff is unburned stuff.
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
Thank you all for the responses, the damper is sealing, I had issues with earlier, and I have checked that, yes there are turbs in the boiler and the tubes and turbs are clean, the sparky stuff is coming from the lower chamber, I get a lot of coals in the lower chamber when gassing, it literally blows them into it. The other odd fact is my chimney has just a light tan/grey dust on it, however the extension on bottom of the tee directly after the boiler will fill up wwith ash in a week to ten days, its about 14-16 inches long and will be 3/4 full at least.
Bruce I know it is a lot of storage but it is what I have and the boiler was priced right. As far as calling Dale I have tried but have not gotten much help, I will leave it at that so as not to complain. the weird thing is I get the rumble and the fire in the lower chamber is a nice torch to nothing visible just a roar.
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
I also forgot to mention that my upper chamber does have black gunk on it but it is dry and crunchy, I never see any gooey tar on it
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
@maple1 yes it is used, i sent a picture to Dale of it the blower and the tag, he did not say anything about it not being right but it makes a guy wonder, it sure moves a lot of air and there is no adjustment on the intake or the primary air on a 100, just the secondary screws.
 

3fordasho

Minister of Fire
Jul 20, 2007
1,005
South Central Minnesota
I don't know if your blower motor would be happy on a speed control, but it would be one way to play with the primary air flow.
I know the inducer fan on my Attack is speed controlled but it's not adjustable by me.
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
@3fordasho I might try it some just to see, I have some variable electronic switches that basically switch the power of and on really fast, it shows up as ruduced voltage on a mutimeter because the meter isn't fast enough to read out the on off. I tried a little with a fan controller and it was ok for short times, but it acted like it almost need the full force for secondary to work right but needs the primary air throttled back some, unfortunately there is no adjustment for that on the econoburn, not that I couldn't fashion something.
 

3fordasho

Minister of Fire
Jul 20, 2007
1,005
South Central Minnesota
@3fordasho I might try it some just to see, I have some variable electronic switches that basically switch the power of and on really fast, it shows up as ruduced voltage on a mutimeter because the meter isn't fast enough to read out the on off. I tried a little with a fan controller and it was ok for short times, but it acted like it almost need the full force for secondary to work right but needs the primary air throttled back some, unfortunately there is no adjustment for that on the econoburn, not that I couldn't fashion something.

Yea that's the problem, it would mess with your secondary air flow too. It really does seem like there is too much air thru it though. Frustrating I'm sure. As you mentioned I would fashion a throttle for the primary air inlet - something that is returnable to the original configuration.
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
@3fordasho I plan to this weekend if I can get the transmission finished in my wifes truck, nobody has touched anything on the wood part, so I assume is it was too wet I would be seeing crappy temps and poor burn, not what I am seeing and not the ash being blown out of the lower chamber like it is, I can tell you if don't have a fire going and close the bypass with lower door open it will blow ash and the smaller coal pieces out of the lower chamber, if I open the bottom door during a burn it will throw hot embers out, glad its in my garage where that is not a huge concern.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,600
NE Ohio
flue temps with an internal probe 8 inches out of the boiler collar will run from 400-650+, tubes are clean, circ is a 26-99 on any of the three speeds, true 1" id lines about 17 feet long from boiler to storage. It will burn through a full fire box in an hour to hour and half, doesn't matter what wood, a large amount of fine ash gets to the lower chamber, the thing will blow sparks and ash out the chimney outlet. with the blower running and gassing I have -.02 to -.03 water column for draft.
I meant to post this last night...seems I forgot to hit the "post reply" button... :rolleyes:
So this is forced air combustion, right? Really sounds like you are burning hard and fast...can the air be cut back some?
My first thought on the water temps is the same...circulating too fast...but there are plenty of people here that know the water side of this a whole lot better than me!

Back to today...after reading others reply's today...I agree, try to restrict that air intake, even if its just a temporary test method, see what happens. If this is a centrifugal blower, I wouldn't be afraid to put that speed controller that you have on it at all.
Also, is the nozzle in good shape, or all eroded out larger than its supposed to be? I'd guess that would allow too flow, and a bunch of sparks/embers through too.
I've heard of people using cheap firebrick to "restrict" the nozzle when its getting too worn and they are just trying to make it to the end of the season to replace it...sounds like it works.
Have any pics of the inner workings of this thing...including the blower...
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,600
NE Ohio
Page 21 of the manual suggest that the blower can run at various speeds.

Also, this pic shows what appears to be an adjustable shutter on the blower
1607654542234.png
1607656064362.png

Does look like this one tends to spit hot embers out too...a little research shows that the blower is a Fasco A1000...as in 1000 CFM! Sounds like a lot to me!

1607661458824.png
 
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cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
@brenndatomu mine is a 100 and it does not have the shutter and is a smaller blower, the nozzle is worn some on the top edge but still the correct width. After talking with @airlina last night, I think we may have found the issue, not completely positive yet as I didn't much time to work on it last night. The bypass flapper appears to be slightly opening as the unit warms up, I was able to wedge the control tighter into the closed position last night and that lowered the peak temps down to under 500 for the first 3 or so hours, that initial load burned out at about three hours, I then reloaded and apparently the bypass had warped some because the temps climbed to 550-560 shortly after closing the bypass, I will investigate more this weekend, I am rebuilding the transmission in my wifes truck so I have to get that done tonight and tomorrow then I can investigate the boiler more. Thank you all for the input.
 
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cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
Thank you @sloeffle for the like, after talking with Bruce @airlina i learned more about Dale and I am glad I didn't elaborate on that, I will not bash someone ever, I will keep the forum updated but more than likely not until Monday, internet is sketchy at home, I really appreciate all the thought and input form folks here and Dale, I was frustrated and have been having issues with this boiler and other things, I like the boiler and the quality, I am going to do some more checking based on Bruce's input and then I will try others ideas if that doesn't fix it. I am not criticizing design or build. I know for a fact I have seen engine cylinder heads that were cast in the same molds and one will flow way more air than another, and I wonder if that is part of my issue, this fan flows more, the tubes flow more than others of the same make, perfect storm thing, just thinking, after last nights experiments I think I have found some if not all of the issue, time will tell, glad to have all you folks to bounce thoughts and ideas off of. thank you all.
 

Drewby

Member
Aug 20, 2018
45
LaCrosse wi
Hey Buddy!
just for the heck of it I would like you to try to do a calculation on how many btus you are burning and also capturing from the wood. You need to know the weight of the wood as well as water content and also how much you raised the temp of you water tank.
I would estimate you need to burn around 150+ pounds of wood to do raise your storage 40 degrees or so. That’s not including raising the temp of the boiler or any load being siphoned off as it was running. That could easily bring it to 200 pounds or so.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,600
NE Ohio
Hey Buddy!
just for the heck of it I would like you to try to do a calculation on how many btus you are burning and also capturing from the wood. You need to know the weight of the wood as well as water content and also how much you raised the temp of you water tank.
I would estimate you need to burn around 150+ pounds of wood to do raise your storage 40 degrees or so. That’s not including raising the temp of the boiler or any load being siphoned off as it was running. That could easily bring it to 200 pounds or so.
Those high stack temps will add more than just a few pounds to the tally...
after last nights experiments I think I have found some if not all of the issue
That's good to hear...I hope you have found a solution for the long term...can't wait to hear what you did/found...
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
an update for everyone, I was able to work on the thing yesterday, after some investigating I found that the collar that bypass damper seats against is eroded a fair bit in the top 1/4 or so of its diameter, unfortunately that means the collar needs cut out and replaced which is a summer job. For a get me by repair I purchased a 1/8 by 5/8 flat gasket and 600 degree silicone and attached the gasket to the flap. Fired it up last night and flue temps cruised at 375-425 during the first and second load, during the third load as storage was pushing up to 155 the flue spiked up to 500, it stayed there for at least 20 minutes but then settled in around 430 so a definite improvement, burn time stretched out to about 3 hours with box filled to 2 inches below the bypass hole so that was an improvement as well, I will check my improvised seal out tonight before I light it off and see if I am getting a good seal. I can always add some more silicone to dress thigs up more, I covered the whole face with waxed paper before I installed the flap again so that the silicone at the joint wouldn't stick, I was very surprised to see that the paper didn't burn until the very last reload of the night #3 right before bed and the upper chamber was only half empty so it was burning pretty good when I opened her up to load
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
I will keep the updates coming, I maybe never made it clear to all on here but I bought the unit used and as is, the person bought from knew very little history and had not run it, he can chime in if he wants, I put no fault on him, I am getting it better everyday and it may be a little undersized at times, but should work good once I get the kinks fixed. Replacing the collar wont be that bad with an air arc and a welder, that is nothing new to me, the biggest issue for not repairing it properly right now is I would have to disconnect it entirely, drag it out of the garage, then load it up, haul it to dad's shop (3 miles away) do the work then reinstall, if I can get by til warm weather that will be easier, plus I have been a little wrapped up with replacing drums ands bands in my wife's truck transmission, the joys of life. I really appreciate all the help from you folks, that may not fix all the issues but I know for sure it helped.
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
Update of the day, got the bypass flap sealed for sure, was still not seeing temps like most are suggesting, on a whim I spun the secondary screws clear out, wow did it take off, flame went blue/purple and rumble was very noticeable, stack temps spiked to 475 on next reload then settled in around 400, good rumble and clean exhaust, heat output was way better too, going to get a bore scope and have a peak in the air holes in the nozzle, I cant fathom that it needs the air screws wide open when the factory setting is 2 to 2 1/2 turns out. I'll took later today and see what I find
 

Hydronics

Feeling the Heat
Dec 3, 2008
386
Northern CT
One year rodents built a nest behind the blowers in my EKO. You may want to check for the same if you haven't had it all apart yet.
Oh....and if you were Duramaxtinkerer you'd have an Allison and not be wrenching on the tranny. ;)
 

cumminstinkerer

Burning Hunk
Feb 2, 2016
174
central iowa
@Hydronics her truck is actually GM, I don't own a slosh box of any form myself, had one once and hated it, I've had the cover all off and looked, i wonder if the holes in the nozzle are messed up. gonna check them out tonight
 
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