Fine tuning EKO

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Cave 2 I'm thinking of the same thing with the primarys.Probly some kind of rod with locking nut on the slider but I still think that sence the fans arn't used to there fullist If I could seperate the primary from secondary all could be controled from the fan covers
 
Superman said:
Just fired up my EKO last night. I'm still in the learning phase and trying to get it set correctly.


Is it safe to adjust the Primary and Secondary air opening as well as the blower opening when there is a burn happening?

I see in this thread people referencing how accurate the manual is for settings. I’m looking at page 18, there is a diagram. Is this what people are talking about? If so, I have no Idea what my Chimney draft is and I don’t have a meter to test the moisture in the wood. Should I get a meter and figure out what the Chimney draft is?

How does the front cover come off?

Page 18 shows you the opening sizes for primaries and secondaries also shows the fan opening which on your 40 I belive you have should be 100 percent on fan opening NOT 10 like it shows. Page 19 shows where the location of where the adjustments take place. Remember thhis is a starting place for you depending on wood type and moisture in wood ect.

Rob
 
Superman said:
Just fired up my EKO last night. I'm still in the learning phase and trying to get it set correctly.


"Is it safe to adjust the Primary and Secondary air opening as well as the blower opening when there is a burn happening?"

I see in this thread people referencing how accurate the manual is for settings. I’m looking at page 18, there is a diagram. Is this what people are talking about? If so, I have no Idea what my Chimney draft is and I don’t have a meter to test the moisture in the wood. Should I get a meter and figure out what the Chimney draft is?

"How does the front cover come off?"

On the 40 there is a panel in front that the blower is mounted to. The panel is fastened with 12 screws.

"Is it safe to adjust the Primary and Secondary air opening as well as the blower opening when there is a burn happening?"

Secondaries and the blower can all be adjusted from the outside of the panel but primaries are only accessed by removing the panel. Safe says you should wait until the fire is pretty much out before trying to adjust the primary air sliders and I would recommend that approach until you are well versed with your boiler.
Chimney draft is important and not to be ignored but because you have a forced draft (blower) you can still achieve an optimum burn setting.
Page 18 is the diagram and page 19 shows a "60" primary air slider controls. And we're all learning (or at least we hope we are)...Welcome to the forum
 
Superman,

While the wood moisture content and chimney draft are important, if you stand back and take a look at the various numbers, they don't change that much with the chimney draft. For example, the EKO 60 recommended setting is 10 mm opening for the primary air with and 0.04" draft, and 9 mm with 0.08" draft. Barely enough to measure and set that accurately with the crude setup they have. The same with the wood moisture.

I agree with Cave and the others on this thread. The factory settings will get you into the ballpark, and are a good starting point. After that, it is a matter of trying to understand what each of the controls does, and to tweek the settings to get a clean, efficient burn. This thread has been really helpful on that. I am still making small changes to the fan opening settings, and the secondary air screws. The changes are small though - usually only 1/2 turn or so in or out on the secondary, and small adjustments to the opening on the fan. If the wood moisture changes by a lot, as per the manual, you would be enlarging most of the settings slightly with wetter wood, or the reverse of course if you wood is drying out further as the season progresses. So the manual shows a starting point, and a direction to take as your fuel conditions change.
 
Kemer, you have a problem if the secondary pipes are not equal distance showing out of the front of the boiler but this is a common problem on these EKOs(see Eric Johnsons EKO pic with the front panel removed the pipes do not match he had his fixed also) ..The pipe has holes in it that lead to the refractory nozzles THESE HOLES ARE CRUTIAL AND MUST BE ALLIGNED PROPERLY which may require you to rotate the secondary pipe to reallign the holes..The pipe on the left should have the holes toward the middle of the boiler 3 oclock, the pipe on the right should also have the holes toward the middle of the boiler 9 oclock..Turn the secondary pipe to match the refractory holes and then lightly tap the pipe back into position, the pipe came from the factory tac welded in place you can retac it or run a good bead around the pipe but it needs to be fastened one way or the other..I want to thank everybody on this site for shareing their experiences good and bad, THANK YOU ALL!!!Dave
 
Cave2k said:
You guys type fast or I would not have posted this much here.
The fire will consume the O2 above it in the primary chamber but the fire will continue to feed from the secondaries. Perhaps the placing of the suggestion was inopportune. Sorry, this is not related to your experiment because you were under power and fed O2 to the primary chamber and created Puff the magic dragon so please don't mix the two. You are absolutely right in "DON'T TRY THIS AT HOME". The scenario I was referring to is a power outage emergency situation where you get a run a way boiler and especially for those that were wondering if they want to move/fix the placing of their secondary air supply dampers so they could get a complete air lock. The huffing and puffing may very well occur even without damping down the secondaries. My statement was to identify the remaining O2 supply and stop it. The lack of O2 will extinguish the fire but remember the refractory is still VERY HOT so the wood gasses will still be produced by infra red radiation until the refractory temps are brought down. You will still get a hot boiler but it should be for a shorter duration. It sounds odd but IF you can safely remove the wood from the gassification chamber and replace it with cold and preferably moist wood you will dissipate the heat in your refractory much quicker and perhaps avoid even a short term overheat.

For fine tuning, on my EKO40 I now have my primary air intakes down to 7mm and my secondaries open to 5 turns and am jetting nicely. The very blue/white/yellow flame fills/covers my U blocks extremely well and my blower opening is only about 1/8th of capacity (12.5% open). Any thing above that on the blower needlessly consumes wood and blows out the gassification by over jetting. From cold to hot the boiler is a little more temperamental until it hits 140*.

Now that is done I intend to work on an external mechanism to adjust primary air with out always taking the 12 screw front panel off so adjustments can be done on the fly with out shut down. The mod will require one hole about 5/16-3/8" and one hole about 1/8" in the front panel.
Question/s for those of you with other than 40 sized EKO's:
How far up from the inside face of the opening are the bolts that hold your primary air control slider plates?
How far from the sides is center of those bolts?
How far apart center to center are those bolts?
If there were a metal bar placed across those bolts would it interfere with the functioning of the back draft damper plate that is on your blower/s?
How far do your slider plates move when full closed to full open (not total movement but just fully open)?
How wide is your front cover panel?
And (LOL) do you have a spare arm and a leg and how much time can you devote to conjectural, pivotal contemplative R&D;and how often? Would you rather split would or wood? :)

I've been thinging of a fix but haven't had time to try. since the primary air comes out in the upper chamber why not just make a slider to cover the opening that you could then adj like on the inside. You could make a cover and bolt it inside and adj it that way. I've got some stainless and as soon as I get some time I'll give it a try. Right now I'm trying to get my modulating valve and control system tuned in as well as installing my stack temp probes so I can get something to compare things to. Once I get my controler hooked up to the state I'll have to see if I can use that info also. I just need 26hrs in a day.
leaddog
 
[quote author=" I just need 26hrs in a day.


leaddog[/quote]

Les you should retire so you have more time.......... Oh yeah thats right you are retired!!!!!! LOL!!!
 
Tacosteelerman, I thought the same thing so I bought a flexable light probe.I pulled the front cover and shined the light in each nozzles hole .I saw light at each hole when I looked in the tubes. They might not be alienged perfectly but are close enough till spring when I can shut it down.I also elongated the secondary adjuster because it wouldnt bottom out when I tryed to adjust it.
 
For what it's worth, I wish this thread had been around a long time ago. I've been running with my primaries wide open (as delivered) until a couple of weeks ago. I've never had the blue flame, although I'm sure I will now that I know it's possible.

Thanks to all who have done the hard work to get this information and share it.

I'll do another calibrated efficiency burn once I get it dialed in.

It would be great if someone wrote up a concise summary in a new thread to make a sticky.
 
nofossil said:
For what it's worth, I wish this thread had been around a long time ago. I've been running with my primaries wide open (as delivered) until a couple of weeks ago. I've never had the blue flame, although I'm sure I will now that I know it's possible.

Thanks to all who have done the hard work to get this information and share it.

I'll do another calibrated efficiency burn once I get it dialed in.

It would be great if someone wrote up a concise summary in a new thread to make a sticky.

You get it really dialed in and you'll be down to burning two medium sized bushes per season.
 
This thread is getting very long, so perhaps I should post this question as a new topic. However, it is a continuation of the "EKO tweek" theme.

Cave - I have been experimenting with the fan settings, following your suggestions of more radical reductions in the fan blower settings to reduce combustion in the primary air and the upper chamber, in order to reduce bridging and extend the burn.

First off, I am not always sure of what people are referring to with the fan settings. I have the newer controller, so I can set both my fan speed, in 10% increments, plus the opening of the pie-shaped covers (dual fans for the EKO 60), expressed either in % opening, or as estimated in inches for the outermost slot.

While I have been getting good burns overall, and have adjusted the secondaries to get blue flames on both nozzles, I have still gotten bridging of larger loads of wood in the upper chamber, although overall, if I am careful loading, it has not been a major problem. So I tried Cave's advice. I have the fan pie-shaped openings set at about 40% open (estimated) which measures right around 1.25" as measured on the outermost slot. The blower speed setting on the controller has varied from 100% to 80%. Based on the high volume and jet-like sound of the nozzles, with a good bed of coals established, I cut the blower power back to 60%. I still had blue flames out the nozzles, but as per Cave's observations, I found a lower fuel consumption, and no bridging - at least over the course of the day today. I also noticed the heat output was just as good, and I found the unit running on idle frequently, as the tank was fully charged with 180F water with the boiler set at 190F.

I'll keep experimenting with these settings, reducing the fan air volume even more. However, I am wondering if there is much difference if I reduce the fan cover open area, vs. reducing the fan speed with the controller? Since the supplied air feeds both the primary and secondary circuits, it seems either method should produce similar results. Splitting the supplied air between the primary and secondary circuits is accomplished with the primary air slides and the secondary tubes/shutters. So does it make any difference if I close up the circular air slides, or just reduce the fan speed via the controller?

I may try to reduce the fan speed even more. So far, 60% fan speed, with a 40% opening seems to be working pretty well. I am out at 4.5 turns on the secondaries - but given all the variation in the tube placement, this may not mean much. I have the primary air slides at 10 mm.
 
Part of the problem is that some are using older boilers with old controllers with only one way to decrease speed which is with the pie shaped fan covers and apparently the new boilers you can change the power setting which I didn't realize. Pretty soon, we'll need road maps!!
 
Boilerman,
That's right on the money as far as air supply. Slower velocity or lower volume equates nearly the same. I have the old controller as sdrobertson points out so the only way I can slow velocity/volume is to cut potential volume with the slider. I'm yammering myself about getting the newer control (just as a back up of course
). My blower has to be set (slider) near 10% open in order to keep from getting burn out pockets and my primary air is set at 7mm and I still have a bluish flame that fills my secondary blast blocks and jets real well. The secondaries are at 5 turns out from closed. Because of welding beads at the top of each of the primary slider openings I can't reduce my primary supply with out tailoring my primary slider plates.​
 
GUYS am I confused as to which controler I have, I have EKO standard, when they first turned them from 220 Volt I have a transformer in mine to knock the power down if you want to use 220 I am going to up load a pic or two maybe you can tell me what is goin on???I always thought I had the old of the EKO design as you can see I have fan speed control..Let me know if you'd like to see the transformer..Dave
 

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TacoSteelerMan said:
GUYS am I confused as to which controler I have, I have EKO standard, when they first turned them from 220 Volt I have a transformer in mine to knock the power down if you want to use 220 I am going to up load a pic or two maybe you can tell me what is goin on???I always thought I had the old of the EKO design as you can see I have fan speed control..Let me know if you'd like to see the transformer..Dave

I have the same controller Tacosteelerman and it is the old model . The fan controls on the back set the duration and interval for the keepalive / purge function where the fans kicks on every so often for so long to push air thru the system. You can check what yours are set at by pushing the test button and rotating the knobs.
 
Tacosteelerman,

Mine has the adjustment knob on the right, with Stop Start buttons in the middle under the display. It has the model RK-2001U in the lower right corner. When you hold the OK button down, it cycles through the various parameters.

EKO also have a yet newer controller, that is fully digital without the adjustment knob.

I did an experiment last night, along the lines of Cave's suggestions. I have been getting longer burn times and better coal bed formation by reducing the overall air volume, by cutting my fan shutters down to about 40% open area, then further reducing with the fan speed control via the controller. Last night, at 1AM, I had a good solid hot bed of coals and some wood. I loaded it up, and cut the fan speed down to 50% (down from the 70%, then 60% I had been trying). This morning at 8AM, I found the Fuel light on. The upperchamber had a deep bed of coals and quite a few pieces of wood left, but no real fire. However, upon opening the lower door, I had a fire going and the coals glowing red again within a few minutes. Within probably 5-10 min with splits on top, I had a strong fire going with great gasification, with a good blue flame, even using the 50% fan setting.

So there is a lower limit to how much to cut the air supply, either using the fan shrouds or the speed controller. I am back up to 60% on my controller now, leaving all the other settings the same. I think I am looking for a setting that will give the wood in the upper chamber enough time to pyrolize and break down, while still maintaining a strong even fire throughout the load. My situation is similar to Cave's however, in that I have a very large heat load with two homes to heat, and undersized storage (500gal). So I am running the EKO almost like it had no storage at all. At the other extreme is Nofossil's setup, with large storage capacity compared to the burner size. In that case, a flat-out 100% burn is more appropriate. Also a note here, that I am not seeing evidence of cresote formation even on the low air settings. In all cases, I am getting a blue flame.

Following everyone's thinking in this thread, it is like tuning a carburetor. The ratio of the primary air/secondary air settings is controlling the blue flame and setting up the actual burn efficiency. Then, it seems more or less independently, the total volume of air (via a combination of the fan shroud setting and the fan speed, if available) will control the overall rate of burn, plus impact ancilliary issues such as bridging, by burning holes in the wood load too quickly (which is of course dependent on the wood, its shape and size and how it is loaded).

At least I think I'm starting to get a handle on what to change when I see a particular problem.
 
ok, i am trying to keep up with you guys. i haven't bought my EKO yet. i been lurking and reading so im not in the dark when i do buy it. but reading this stuff is all "german" to me. i hope once i get this EKO and actually see what you guys are doing it will come to me.

but, a new thread for "fine tuning" and stickied would be a excellent idea. 5 pages is just to much and they will get overwhelmed like i am.
 
Alright I hope I can keep this short.
To recap, this is my 4th season with the Eko 60. When I got the boiler, I recieved a crappy manual. Since finding this forum last fall, time and time again many of you were referring to the new manual that I think Eric had much to do with the rewrite. Until today I never actually looked at it, so I blame myself for that.
Help me then understand a couple of items in the air adjustment page. What are the number readings for the chimney-what do they mean?
I am certain that it says to open the primary air to 9 (mm?). I have been running all of this time at about 3/4" opening.
Having said that, I went ahead and moved the opening where suggested. Now as of this post, I had lots of smoke and a really hard time on the restart. Seems to me the primary chamber now starves for oxygen, because when I open the primary door, I can get the flame to come back.
I am not able now with a load of wood to change the primary adjustments, so like you guys it wood be nice to have a way to do this without taking the panel off.
when I started up the fans I had gasification for a few minutes. I noticed right away howslow or labored the ball of orange was. I played with secondary screws and the fan openings but could not gain any blue.
I will give the burn some time to fester and see what happens when all is heated up, but I definately have taken a step back with the manual books suggested adjustments (very visible smoke still out the chimney too), so I'm not sure what to make of all of this now.
This is just my experience so far.
 
Just to add to the above, I do not have a moisture meter so I don't know what my wood is, so maybe it is not as dry as I think it is, thus might explain why having the primarys open so far before worked for me. But man, I had them way open compared to what is suggested.

Also when I think of bridging now, does allot of primary air push some of the good ashes through the nozzils and result in more ash at the bottom chamber, and help create more bridging possiblities? Maybe. As I said above, I have been conditioned to hear and see a more forceful blast than what I just saw at these settings. Maybe the flame is soppose to be a more kinder-gentler flame. I just am not sure now.
 
A couple of questions - did the tape stay on the secondary tubes so that the covers will cover it? 9 mm is .345 inches which I found hard to figure out so I went with 7/16 (12ish mm) as I could use a regular builders scale to measure, as a starting point. I had better luck with the tape covering the tubes but now that I replaced the metal disks with the electrical covers it seems to regulate the air better. I closed by fan covers to about 1 inch and I am pleased with the outcome. Its hard to figure the sweet spot but I'm seeing that the primary's are the key(which is a pain as this adjustment is harder to get to). Another thing is check to make sure that your not leaking any air out of the front cover around the gaskets and our old stoves have allot fewer screws holding them in place as the new ones do. I ended up using the metal tape to seal the front down the sides where there is only one screw holding it.

I would open the primary's between 3/8 and 7/16 and figure out how to fix your secondary tube covers. Without that fix, I don't think you'll get very good results as the secondary's are allowing way to much air through. 3.5 turns on the secondary and 1" to 1 1/4 on the fan covers.


EDIT-just read your next post-The bridging is partly because we're burning the secondary's way to hard. If you question your wood, start with 7/16 to 1/2 inch.
 
I just seem to be having the opposite effect than you for some reason. I did the tape trick for a while, but I gained more orange and labored flame.
I was not sure about mm either, so I simply used a 10mm open box wrench as a guide. When I really looked at it hands on, I could not believe I was suppose to bring in the primaries that far.
I've got to say I am going to put everything back closer to where I had it-I think. But maybe all things are equal, because I usually liked the fans opened only 1/2 inch most of the time(again at where I had my previous settings).
 
There is a lot here. So first: Primary air control sliders are the major control for primary air but blowers set too high can skew even the best primary and secondary settings. Over turbulent primary air is initially responsible for burn out over the nozzle. (Unless you have a way for secondary air to go up through the nozzle and exit the primary chamber. That would mean secondary air has to over power primary air to create burn outs unless there is enough secondary air to create a vortex. If secondary air can create a vortex it is too strong and the only thing that can make it that strong is the blower and the secondary air settings. UNLESS you have a back pressure problem. Back pressure is caused by dirty or partially plugged chimney or heat tubes at the back of the unit. Plugged heat tubes will cause gassification problems. Plugged heat tubes can be caused by improper gassification/burn settings and lots of idle time and I've had them). Before any of us is willing to pass off our burn problems as unique we should be sure all of the fundamentals are in order. Are the heat tubes clean? Have the secondary air tubes broken free and moved or are they plugged? (Some 60 owners have found that their tubes have moved and the tack weld that held them in place is broken which also means they could have rotated and are now not in alignment with the holes in the refractory.) As per the new manual for all EKO models 9mm to 12mm is the recommended setting for primary air that is roughly 11/32 to 7/16" variable gap and any opening above that is apt to over pressurize the primary chamber. Unfortunately some of the 60 owners have adjusters that do not come in complete total contact with their secondary tubes. This means that the adjusters really shouldn't have to be opened as far as the manual suggests because the tubes are already partially open. Are the holes for secondary air in the refractory clean or partially obstructed? Are the back draft damper plates on the back side of the blower/s moving freely? My tubes on my 40 have not moved but I have found ash deposits in the tube. Over all we are talking about certain laws of physics that apply to the gassification process and those laws are the same for all of us if our units are built and remain as the design was intended. If primary air is not overpowering and secondary air is not over powering and if the blower/s are not over powering we should be able to get an adjustable flame that can be set to the hottest possible temperature and burn the least amount of wood possible. Those who have tubes that have moved/broken free might still be under warranty and should probably seek aid.

The tuning principle: Primary air pressure (supply) should be consistent but not too forceful or the fuel ratio will be skewed. Secondary air should supply enough oxygen to permit a jetting flame that is blue based in color that turns to white and yellow and fills the nozzle/s. If your flame will not change from orange to blue no matter how you adjust your secondary air you have too much primary supply. (unless your secondary supply is blocked or partially blocked or your heat tubes/chimney are plugged). Cutting your blower/s back is the first part of fine tuning your EKO. (it is hard to see what you are adjusting when the unit is running full bore). Setting your primary air according to the manuals recommendations is necessary for proper carburetion. Secondary air should be set as per the manual (where mechanically possible) as well as too much secondary air can create excessive turbulence that can cool the fire and hinder output as well as prevent a complete burn. (All units need to be clean and mechanically correct to achieve proper gassification). If the flame turns back to orange or the unit smokes when you start readjusting your blower/s it is probably because your heat tubes are restricted and need cleaning. Once again over adjusting your blowers can frustrate the adjustments you have just made in fine tuning your boiler flame. Bring the blower/s up slowly until the blued flame fills the nozzle and the fire blocks. You should be good to go but you may find you need a little more blower supply if you come back and find your boiler calling for fuel and you have a good bed of coals.

Because of design primary air settings should only be done when the boiler is cold so it may take a few times to get the settings where your boiler will function best. This is just my two cents but I hope it helps...
 
Thanks Cave, everything you said is good stuff.
I had a phone coversation with Srobertson, and now I have things moving in the right direction. I re taped the secondary tubes to restrict air, and have the primary set at 1/2 inch. I had to hurry because I had a partial load in the chamber and it was getting hot. Upon restart I saw something beautiful. I had a gasification mushroom like I had never had before during my 3+seasons of burning. Now I have been conditioned to not get to excited, so I am going to be tweeking and studying the burns over the next several days.
I have been used to a tight straighter flame with some power behind it. Now I have a more gentle cloud with a mixture of nice colors. Lots of blue and light yellows. Makes sense that this setting could be a mojor wood saver, but again I'll have to report.
If this all pans out, I owe you guys a solid.
 
Wow, I'm thinking Cave2k has gotten it pinned down and its ready for the sticky. Excellent and easy to understand. It was a pleasure to talk to Barnartist last night and to get these older stoves figured out. It was frustrating for both of us to read on the forum how people could move the secondary air a half a turn and see results. With the disks not covering all of the secondary tubes, we could move the damn things 6 turns and it wouldn't make any difference. I honestly figured that you guys were just kinda making up how well you were burning. I was coming from a Central Boiler owb and I was happy with the cut back in wood I was using so I really didn't know any better. I wish there was a way to figure out how many boilers were sent to the US with the secondary's misaligned. I'm afraid there is allot of unhappy boiler users out there that haven't found this forum yet. To those individuals that are reading this and wondering why someone would spend so much time on a supposedly simple and efficient to use boiler - it is simple and easy to use - its just a learning curve and its well worth it.