Fine tuning EKO

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barnartist said:
Thanks for the update Shannon. I'd like to get to where you are, but like you said it is a border line addiction to mess with these boilers.

Today I cleaned out my exchanger tubes (I have the old model that does not include the exterior cleanout arm) and my stack dropped about 100F at normal operating, so I must be making a better air to water echange back there. I was lazy this year to get back there, so I should try and clean out more often.

My boiler was down this summer for a cleaning and I have the 40 Super with the cleaners in the tubes. The cleaners are 1 1/4" twisted flat stock steel and the tubes are 1 1/2" diameter. Theoretically that leaves and 1/8" crud on the inside all the way around in each tube. My temp transfer was great for about a week and then dropped down to really nice and has stayed there since. I really need some 1 7/16" or 1 3/8" twisted flat stock to keep the tubes good and clean with out having to take things apart since I have a lot of idle time and will have until I can get my storage up and running. I wonder how much the crud in the tubes effects the "ideal burn" we are all wanting to have????

Any way my point is the built in tube cleaner is really nice but I still have to clean my tubes too and I'm thinking all the time all of us has spent burning with less than the peak fire has left a lot more tubes cruddy than we would like to think. :cheese:
 
I didn't clean my tubes at the end of last season, but Zenon recommends doing it.

I'm pretty happy with the new controller. I think the greater temp range helps keep the boiler from going into idle. Think about it: you've got 20 degrees more range on the top end, so you get longer, hotter burns. Hotter water in the system makes everything more responsive, and a hotter-running boiler gets better, more reliable gasification. And I haven't even started fooling around with the settings. Probably should do that before the next cold front moves in the end of this week.
 
Glad to see you finally installed that controller Eric. I really want one, im just too cheap right now to buy it.

Cave, I think there is a whole other discussion to be had on the tubes and the heat echange back there. Iv'e seen my stack creep up the last couple of days for similar burns, so Cleaning those suckers seems to be a necessary evil. Its a pain for me to take out my homeade spirals and do that, but when finished I really kick some butt on the next burn. It's tough to watch the top of the stack sometimes and see that "hot black summer road" look if you know what I mean. Seems like a waist. Lets catch some more of that heat.
 
I went out this evening and put square pieces of sheet metal under the primary air regulator plates, which in my case won't reach far enough to close the passages down to the 10mm size by themselves. That worked pretty slick and I set the openings for about 10 mm or 1/4-inch. I re-set the secondaries to 6 turns and set the sliders on the blowers to about one inch. Then I set the fan intensity to 60% and fired 'er up.

That didn't work at all. I couldn't get sustained gasification and the boiler didn't heat up. Well, it's a pain to take the blower plate back off, especially with a firebox full of burning wood, so I fooled around with everything else in an attempt to get it going right. No dice. After dinner I took the plate off and removed the sheet metal, leaving openings of about 1" on each side. I set the blowers to 100% and launched a beautiful gasification event. Orange and yellow flame roaring.

Then I started playing with the fan intensity. I found that 70% yields a beautiful blue flame and steady heat output. I'll load it up as usual shortly and see what we've got in the morning. I like the blue flame. I think that's the goal Cave and everyone else who has contributed to this thread is talking about. Getting a longer burn out of the same amount of wood is a worthy goal.

For those with EKO 60s and 80s with the old controller, I think you can get a similar result by shutting down one of your blowers after you get a good fire going. Turn on both blowers on startup, and then switch back to just one once the thing is up to speed. I bet you wring more out of your wood supply that way.
 
Eric, your description sound allot like mine, I had trouble on startup, lots of smoke and could not get it to fire (when I closed down the primary more). So I also had to open the primaries back up, but more like 5/8 I think. However, I remember you always like 6 turn on your seconds, seems like that would need to be way down to match the primary opening, talking about when you tried to close it off more.

I can close off my fan openings completely and still get a lazy gasifying flame like others have talked about.. Don't understand that one. I just need to make the modification to adjust those primaries on the fly.

Oh, I cooked a chicken and some taters in the gasser this evening. Turned out nice.
 
I'll have to think about that one.
 
barnartist said:
Cave, I think there is a whole other discussion to be had on the tubes and the heat echange back there. Iv'e seen my stack creep up the last couple of days for similar burns, so Cleaning those suckers seems to be a necessary evil. Its a pain for me to take out my homeade spirals and do that, but when finished I really kick some butt on the next burn. It's tough to watch the top of the stack sometimes and see that "hot black summer road" look if you know what I mean. Seems like a waist. Lets catch some more of that heat.

It's been deleted now but I sent the dimensions on the cleaner arm, shaft assembly etc. of my boiler to someone so they could build their own. Was probably too much of a project. All I have to do is make some wider scrapers to go into my tubes and I haven't done it yet. So I am not surprised I haven't heard back on "their" project. Wider scrapers would allow the tubes to be cleaned more efficiently, allow the tubes to transfer more heat, open up the exhaust flow and maybe allow more heat/better burn. Kind of like taking the baffles out of an old 2 stroke dirt bike???? Another one of "those" projects. I'm still trying to get at building a flexible smoke baffle for the upper chamber. Days are too short I think but I'm glad they aren't any longer...........

Eric, I measured my nozzle opening also. It is 8 1/2" x 1 1/2". It seems the 60 is a twin version of the 40. I was thinking of putting a short piece of firebrick , up top, between the secondary air outlets to see if I could force a better burn. Just have to scrounge to come up with some "test" materials........
 
I remember that post Cave. Nice job on that one as well. It did seem like allot for me.

I'd like to have a quicker way to get that back cover off, skip all of thos bolts, but maybe they are necessary for a good seal. Seems like there is some kind of flip bolt hardware, or something with a small handle that you can pull up or push down by hand. Anyone know what I'm blabbering about?
Somebody on here uses a good wire pipe cleaner thats just the right size, im sure it does a much better job than the round iron tool provided (at least for the older Eko)
 
I know what you're talking about but you probably have to do a search at Grizzly.com(found them at Grizzly. They're called toggle clamps #G1774), Northerntool.com or some specific hardware outlet. Ace or Tractor Supply might have something like them in a catalog. The ones I am used to seeing were used for covered grain augers. Some flipped up from the side and had an over center cam-lock you could really reef on. Others were on a flat surface that kept a heavy removable panel in place. Good idea.

I had a couple of pins in my Super's tube cleaner pop out that released the spiral cleaners and ended up plugging two tubes by about 30-40% and locking the cleaners in place this last summer. (idle burn times again) I disassembled the whole cleaner and built a special cleaning tool I could use in a cordless drill to clean the tubes. Using a 15" long shaft 1 1/2" wood bit, which I trimmed about 1/32" from the sides of the blade, and a couple long drill bit extensions, I came up with a tool that would go the full length of the tubes down into the secondary chamber and out again. Two passes per tube with that was all that was needed and probably didn't take over fifteen seconds a tube except for the really plugged ones. having a snap closed lid access panel for that would really be quick.
 
Eric Johnson said:
I went out this evening and put square pieces of sheet metal under the primary air regulator plates, which in my case won't reach far enough to close the passages down to the 10mm size by themselves. That worked pretty slick and I set the openings for about 10 mm or 1/4-inch. I re-set the secondaries to 6 turns and set the sliders on the blowers to about one inch. Then I set the fan intensity to 60% and fired 'er up.

That didn't work at all. I couldn't get sustained gasification and the boiler didn't heat up. Well, it's a pain to take the blower plate back off, especially with a firebox full of burning wood, so I fooled around with everything else in an attempt to get it going right. No dice. After dinner I took the plate off and removed the sheet metal, leaving openings of about 1" on each side. I set the blowers to 100% and launched a beautiful gasification event. Orange and yellow flame roaring.

Then I started playing with the fan intensity. I found that 70% yields a beautiful blue flame and steady heat output. I'll load it up as usual shortly and see what we've got in the morning. I like the blue flame. I think that's the goal Cave and everyone else who has contributed to this thread is talking about. Getting a longer burn out of the same amount of wood is a worthy goal.

For those with EKO 60s and 80s with the old controller, I think you can get a similar result by shutting down one of your blowers after you get a good fire going. Turn on both blowers on startup, and then switch back to just one once the thing is up to speed. I bet you wring more out of your wood supply that way.

After my earlier post where I had a nice blue high intensity flame on 1/4 primary opening I ran into some problems recreating that output and had results like Eric explains above. The beast would run and run and stay at 71c with poor gasification and water temp at 150 / 155 then sometimes go up to 73 then drop back to 71 .I tried for a several days to adjust the fan and secondaries and found I could get a nice burn some of the time but it took alot of tinkering. In the end I have went in and opened the primaries to 1/2 inch and now seem to be back to getting good consistent gasification going again with secondaries 2 turns open and fan opening at about 1 1/4 inches now I can keep it pushing out the heat while I try some more fine tuning
 
As I mentioned in another thread, I've had good luck in recent days changing the fan speed under different conditions. I start and rekindle fires with the fans at 100%, and then back off all the way down to 50% when I've got a good fire going. The you get the blue flame, long burns and a nice, clean secondary combustion chamber in the morning. Being able to modulate the fan speed is really nice when you don't have storage.
 
Gentlemen,
The background. I’ve been reading this forum and others here for several years. I’ve burned wood for many years where I used to live. Currently I have an EKO 80 that I’ve been running for about 2.5 weeks now. It is placed in a detached garage that I built this summer. I built a 7X14 insulated boiler room in the garage for the boiler, pumps, piping and expansion tanks. The rest of the garage is unheated. I do not have any storage at the moment, but am working on 1000 – 2000 gallons of storage as soon as I find some tanks. I have about a 110’ run through Logstor insulated PEX piping up to my house. The house is a one story (2400 sq. ft.) plus a full basement (another 2400 sq. ft.). I have a heat exchanger in my forced air furnace and a side arm on my hot water heater. The house was built in 2001, has lots of high efficiency windows and 6” insulated walls everywhere. We are in central Wisconsin so our temps are colder than some here and warmer than others. We are burning maple that was cut and split over a year ago and stored under cover.

Now, the good news. I started with the following set up for the EKO 80, essentially the “factory” settings. Primary air at about 3/8” open (about 9.5 mm) which is as closed at they will go by the way, secondary air at 3.5 turns out and fan openings at 100% open. I ran a couple of smaller fires for a day and then loaded the sucker up full. It is a big firebox in case anyone cares. It holds about 50 pieces of averaged sized split 16” long wood. Running these settings, I normally have 24 hour burn times. The shortest has been 21 hours and the longest has been 28 hours. I have been keeping the house at 72 F and the entire family is very happy.

Now the bad news. This things smokes all the time. It smokes a little bit while idling. It smokes like a Central Boiler when it’s running. I can get decent orange to blue flames out of the nozzles some times but it still smokes. Normally it only gasifies out of one nozzle, but not both. It always smokes out of at least one nozzle. I’ve tried changing the secondary air inlets anywhere from 2 turns out to 6 turns out. I’ve tried moving the fan openings from 100% open to 25% open (about ½” open at the widest point). None of the changes I’ve made have done anything. I think that the secondary air adjusters line up with the pipes, but I won’t swear to it. How do you actually check? Also, I appear to have the “old” controller. The back of the controller has knobs for fan speed control, but they don’t seem to do anything for fan speed. I am not really happy to spend the $$$ that I did and get the “old” controller.

In summary, I love burning wood and we all love the warm house and long burn times. I am disappointed that I can get some gasification, but this thing always smokes, and sometimes smokes a lot. I really, really would appreciated any help or advice anyone can give me to help adjust this thing.

Bill the Dog
 
Bill the Dog said:
Gentlemen,
The background. I’ve been reading this forum and others here for several years. I’ve burned wood for many years where I used to live. Currently I have an EKO 80 that I’ve been running for about 2.5 weeks now. It is placed in a detached garage that I built this summer. I built a 7X14 insulated boiler room in the garage for the boiler, pumps, piping and expansion tanks. The rest of the garage is unheated. I do not have any storage at the moment, but am working on 1000 – 2000 gallons of storage as soon as I find some tanks. I have about a 110’ run through Logstor insulated PEX piping up to my house. The house is a one story (2400 sq. ft.) plus a full basement (another 2400 sq. ft.). I have a heat exchanger in my forced air furnace and a side arm on my hot water heater. The house was built in 2001, has lots of high efficiency windows and 6” insulated walls everywhere. We are in central Wisconsin so our temps are colder than some here and warmer than others. We are burning maple that was cut and split over a year ago and stored under cover.

Now, the good news. I started with the following set up for the EKO 80, essentially the “factory” settings. Primary air at about 3/8” open (about 9.5 mm) which is as closed at they will go by the way, secondary air at 3.5 turns out and fan openings at 100% open. I ran a couple of smaller fires for a day and then loaded the sucker up full. It is a big firebox in case anyone cares. It holds about 50 pieces of averaged sized split 16” long wood. Running these settings, I normally have 24 hour burn times. The shortest has been 21 hours and the longest has been 28 hours. I have been keeping the house at 72 F and the entire family is very happy.

Now the bad news. This things smokes all the time. It smokes a little bit while idling. It smokes like a Central Boiler when it’s running. I can get decent orange to blue flames out of the nozzles some times but it still smokes. Normally it only gasifies out of one nozzle, but not both. It always smokes out of at least one nozzle. I’ve tried changing the secondary air inlets anywhere from 2 turns out to 6 turns out. I’ve tried moving the fan openings from 100% open to 25% open (about ½” open at the widest point). None of the changes I’ve made have done anything. I think that the secondary air adjusters line up with the pipes, but I won’t swear to it. How do you actually check? Also, I appear to have the “old” controller. The back of the controller has knobs for fan speed control, but they don’t seem to do anything for fan speed. I am not really happy to spend the $$$ that I did and get the “old” controller.

In summary, I love burning wood and we all love the warm house and long burn times. I am disappointed that I can get some gasification, but this thing always smokes, and sometimes smokes a lot. I really, really would appreciated any help or advice anyone can give me to help adjust this thing.

Bill the Dog

Question - why did you decide on an EKO 80? That sucker is huge. With my EKO 40 heating 3200 square feet I don't get to the full-on no smoke operation until my boiler temps are up to 160 and the flue hits 400 or so. It typically takes me about an hour from a cold start to get to this point. It smokes a fair amount for the first 10 minutes (not like an OWB, however) and for the next 45 minutes or so I have a smoke trail that completely dissipates within 20 feet of my stack. After an hour - no smoke at all and she runs like this until she runs out of wood.

I think perhaps an EKO 80 is way too big for your heat load??? Others will likely chime in. Get that storage online so you have somewhere to send the gazillions of BTU's that thing creates...
 
If you're not getting gasification out of both nozzles, then you're going to get smoke. One thing to make sure of is that both nozzles are clear before you put in a new load of wood. You can do that with the hoe cleaning tool they provide with the boiler. Another point is that 2.5 weeks is pretty early in your gasification career--and early in the boiler's life. There is moisture in the refractory that takes awhile to work itself out. When it does, you'll get more reliable gasification. The 80 has lots of refractory, so that might be why it's taking longer than normal. Back to the nozzles: You want to make sure that your fuel is on the nozzles as much as possible. I rarely fill my 60 up all the way. Instead, I make pyramids of wood in the firebox over the nozzles. Finally, you want to keep your boiler as hot as possible at all times. The new controller (you're right--you've got the old one) allows you to go up to 195 degrees and it reads out in F. I just replaced the old one with the new one a few weeks ago, and I'm getting a lot better performance at high temps and by controlling the fan speed, which is something you can't do the the old one. I'd try to ding the dealer for a cheap or free replacement. It's definitely worth it. Out other member with an 80 and a couple of guys with 60s have tried disconnecting one blower, since the two-blower arrangement is apparently too powerful for most conditions. With the new controller, you can modulate the fans down to 50%, which I suspect accomplishes about the same thing, plus you can set it higher at 10% increments. Another thing you can try is to block off one nozzle with a piece of firebrick. That effectively cuts your output by half, but it sounds like an 80 is way more boiler than you really need, so it's certainly worth a try.

Bear in mind that some what you're calling "smoke" is probably just steam. That's the stuff that dissipates 20 feet from the stack and it's usually white. Even "dry" firewood has 15 percent moisture, and it has to go somewhere. You notice it more on very cold days.

Finally (and I mean it this time), if you wood isn't really dry, you're going to get smoke--usually whispy blue stuff. You can get around that to some extent by building a small, hot fire with dry wood, and then toss a couple of not-so-dry chunks on top. If I were you, I'd experiment with smaller fires and more frequent loading just to see if you can get a consistently clean burn. Then take it from there.

BTW, I'm originally from Coloma.
 
With the big boiler you need storage as you are not even starting to run that thing with your load. If you are getting 24hr burn times you are just running it like an OWB with lots of idle time and that is creating ceosote. Then when it starts to heat up it tends to burn off the deposit and shuts down again. Also you need a GOOD bed of coals to gasifiy good and running the way you are you never have time to build up a good bed of HOT coals. With my 80 it will run GOOD when I have a 3 to 4in bed of hot coals and the boiler water is 180+. I have my modulating valve set for 185* so any water leaving the boiler is that hot so I keep the boiler temp high. I also have the pump temp to come on at 170 to help keep the boiler hot.
When you start a fire you need to use SMALL pieces and then put a few larger ones on top (2in dia) and let them burn down into coals. Remember you have alot of refactory to heat and you need the hot coals to lite the gases and keep gasification going. If you have bare open nozzles showing you will smoke.
You can try the one nozzle, I did , by taking a fire brick and placing it over the back nozzle and then load the front like you would with one nozzle. Just don't fill it up and exspect to get 24hr burns. Any thing over 10 to 12 hrs is way to much.
I'm running with my fan at 70% speed, 1 fan only, primarys at 10mm, secondarys 4turns, and the fan opening about 3/4's open.
leaddog
 
Hi Bill the Dog,

Without storage, even though you are trying to heat 4800 sq ft maybe you should:

(1) block off one nozzle (like some others with larger EKO's are doing)

(2) Disconnect one blower (by putting in an on/off switch to select/de-select its usage like some others with larger EKO's are doing).

(3) Reduce remaining blower output to around 35-50%. (")

(4) Reduce primary air to 6-8mm. (reduce further if flow is still too strong)

(5) Turn secondary air controls down to 2-3 turns (maybe open a little more if all you get is an orange flame).
And load conservatively until your unit is up to temperature.
 
I didn't think the blower output setting went below 50%, Cave. Does yours?

Leaddog makes some excellent points, as usual. I've noticed that the bed of coals is critical to reliable gasification. Getting a good bed of coals is a lot easier if you run the boiler hot, like 185-195. You can't get that high with your controller. It maxes out at 176 (80 degrees C). And, it's a good idea to set your main circulator so that it won't kick on until the water is really hot. I have mine set to run only when the return is above 160. Leaddog's setpoint is 170 at the top of the boiler; so we're probably about the same. It works really well. These things like to stay hot.

I'm starting think that gasification boilers aren't really most efficient when you have to continually start fires from scratch. It seems to that all that time spend cooling down and heating up is counterproductive. Instead, I think you should size your boiler/system in such a way that you can run the boiler continuously within a certain temp range. Not sure what that is, but if you're always loading onto a nice bed of coals and getting instant gasification, seems to me that would be the optimum.
 
Eric:
No my blower won't slow down and neither will Bill the Dog's as we both have the old controller I was referencing his blower opening. OOps sorry about that. I've edited that response now to address him. It was kind of general without any real directions to who it was for and while I wrote it leaddog must have posted. Thanks for pointing that out.

Nofossil gets a good deal out of storage with just one burn but if I remember correctly some of them are weather related "long" burns like a load and a half. Maybe we need to hybridize the EKO with the Greenwood concept as Greenwood has lots of refractory "to hold the heat" as they say. With storage having a hot boiler secondary would save on burn time to achieve gasification and might/should have an overall efficiency benefit if you can achieve optimum gasification in shorter time.
 
Eric,

I've got a work around for always having a bed of coals for the next fire. I have a timer on my boiler. Right now, it is set for 5 hours. So, I load the chamber, reset the timer and let it go. I load it once in the morning and once in the evening.

The coals won't always look very hot, but a little air gets them fired up quickly. Upon loading I open the fan shutter all the way for about 2 minutes. (Gassification starts within the first minute.) Then I close them about 50% for about 15 to 20 minutes. By then it is burning very hot and I shut the fan shutters down to maybe 20%.

Doing this requires that the circ pump has an aquastat to prevent from overheating the boiler when the timer stops and shuts the controller off. Or, just shut the fans off with the timer. Just make sure the pumps can run if the boiler gets too hot. I have an aquastat set for 190 deg on top of the boiler jacket.

This method has worked like a champ for me.
 
I stole sled_mack's timer idea, this has been one of my favorite modifications. Lots of coals left for a restart. I use a simple 12 hour countdown timer, and tie the conroller's power to it. I usually set it for 5-6 hours. Champ champ champ! Thanks Mack!

All of my fine tuning has paid off, I don't want to touch any setting it has been so good. Tons of heat, deep blue gases- life is good even in the -11 temps last night. Still a 12 hour cycle and warm tanks and lots of leftover coals. Last season I would have needed 4 loads of wood in 24 hours in these temps. Sadly, I'm running out of things to experiment with...
 
Barnartist,
Good to hear your EKO is performing up to par for you,the big question is do you dare reinstall the blower shield???Dave
 
Yes! I did just that 2 days ago! What does that tell you?
Also, I have been leaning a big piece of bubble foil around the doors- my thought is to help insulate the area, and the intake air might be a little warmer for the mix. Don't know if it does anything or not.
 
sled_mack said:
Eric,

I've got a work around for always having a bed of coals for the next fire. I have a timer on my boiler. Right now, it is set for 5 hours. So, I load the chamber, reset the timer and let it go. I load it once in the morning and once in the evening.

The coals won't always look very hot, but a little air gets them fired up quickly. Upon loading I open the fan shutter all the way for about 2 minutes. (Gassification starts within the first minute.) Then I close them about 50% for about 15 to 20 minutes. By then it is burning very hot and I shut the fan shutters down to maybe 20%.

Doing this requires that the circ pump has an aquastat to prevent from overheating the boiler when the timer stops and shuts the controller off. Or, just shut the fans off with the timer. Just make sure the pumps can run if the boiler gets too hot. I have an aquastat set for 190 deg on top of the boiler jacket.

This method has worked like a champ for me.

Are these mechanical timers you're using? If so, any chance I could trouble you for a model number and a source?

EDIT - Are you guys simply using an Intermatic style in-wall timer for your fans? Seems way too easy...but GREAT! I may have something to add to my list of things to do this weekend. You guys may have eliminated my least favorite part of my EKO - cold starts.
 
When it's cold like this, I'm always throwing wood onto a bed of coals. Instant gasification is the result.

I've been wondering if this is really less efficient than starting from scratch once a day. Seems to me you waste some fuel getting the fire going and getting the boiler back up to temp. You sure waste less time, and it seems to me, less chance of inadvertently leaving the bottom door open and overheating the boiler. You know how it goes.

In this sense, operating a gasifier is really no different than a conventional boiler or furnace. The main difference is lack of smoke and more heat out per pound of fuel.