Fine tuning EKO

[taxidermist]

I think we will have to dink with the fan speed and air to the fans but I think you will not have to mess with the primaries. I too have some weird burning going on with all the wind and cold temps the fire seemed lazy so I bumped up the fan speed to 60 and opened up the fan shutter and it helped a little but when the wife went to start a evening fire the damper was stuck(telling me it was still a lazy fire). She started a fire and when I got home from work at 8:30 this morning the fuel was all gone but tank temps were at 140 also telling the fire was still lazy.


Rob

 

[barnartist]

Since I have the older Eko with no fan speed control, wondering what difference there is in fan speed and the fan air adjustment (shutter).

We were down to 3 other night, definately took some more wood, but I happen to be into a softwood portion of my pile.

 

[taxidermist]

Your fan runs at 100 percent speed and you gate the volume of air with the shutters.

New controller you can run the fan speed down to 50 percent all the way to 100 percent by 10's and then we can also adjust the volume with the shutters.

I think of it as pressure from the fan speeds and volume of air from the shutters.


Rob

 

[Duetech]

The colder weather forced me to radically readjust my settings on my older model EKO40 Super as my boiler went into a tailspin and could not keep up with the high winds and colder air. I have built an external primary air controller so I can make all of my changing weather and changing wood moisture adjustments in just a few seconds. Next I intend to work on the secondary controls so they are more user friendly. I am looking to get one of the new controllers, because of the lower blower settings, so that my adjustments will not have to be so radical when adjusting from one weather pattern to the next . As soon as I can upload the pictures for the external primary air adjuster I will post with a new topic...SEE "EKO External Primary Air Controller"

 

[barnartist]

very interesting Cave. We had 3f the other night now it is suppose to be in the 50's some this week. I certainly could not get enough heat until I opened up the primaries as well. Looking forward to your post pics.

 

[Duetech]

I ended up cutting back on the primary and secondary air controls and opening up the blower. In the past I have mentioned having a blower that just produces what I think is too much air. Now my primary air is about 6mm but my secondary is 1 1/2 - 2 turns and my blower is open to about 80%. My controller will not allow me to reduce blower speed. Having trouble uploading the pic's to my computer. It's a computer land software buggaboo but I am working on it and as soon as I can I will post. Thanks for the interest.

 

[barnartist]

Dear Santa...

1). Tweek my boiler as you slide down the chimney

2). Help Cave get his pics uploaded so I can adjust it myself till you come next year

3). Or forget all that and just leave me about 12 cords of wood in the driveway

 

[CANUCK GLAZIER]

I would def agree with Medman in regards to the eko25 being a bit of a challenge vs its bigger siblings. This thread has really helped me in getting my boiler dialed in over the past week. The wood I am using varies in moisture content so getting the settings right was tricky. I will be pursuing a similar design as Cave2k with an adjustable primary air accessible from the outside of the blower panel.

I have my primaries set at 13 mm, my secondaries set at 4 turns out, fan inlet 25 mm- 35 mm, and my fan speed at 60%. I find that in my case of varying moisture these settings work well as I can regulate the air with fan inlet and speed so that I don't get any bridging or burn pockets, as well as a nice steady burn averaging around 7 hrs with some idle time of course.

Hope this helps

Merry Christmas and God Bless you and yours

Rob

 

[Duetech]

EKO External Primary Air Controller Pics are up listed under new topic "EKO External Primary Air Controller". Oh and Merry Christmas to you all!

 

[Dave T]

I let the EKO burn out yesterday to change my circ and left it out for a while last night so the fat man in red would not burn his touchie on the way in , it worked he was here, he was here my son yelled wakeing me up this morning..All the money on my night stand was still there too so I guess this economy has not hurt santa to much..MERRY CHRISTMAS TO ALL and I hope Barnartist's EKO got the tweeking of a lifetime...Dave

 

[Northwoodsman]

Glad to hear that I am not alone in trying to fine tune my EKO40 system with 1,000 gallons of pressurized storage.

I have been running my system for approx. 2 months now and am starting to make some real progress.

I have my secondary air adjustment at 4 turns and have not had to have the cover off and thus do not know what my primary is set at (factory recommends 9-12 mm I believe).

The past few days I have been able to get full, complete gasification burns without any messing around. It seems like the most important item is that the fire gets nice and hot in the primary chamber and thus creates a good bed of coals. Also, I only load the wood box half full until I get a good gasification going at which point I load it up full. What I have been doing is opening the bottom door for 5-10 minutes after starting the fire and then closing the door. Then, I set my temperature controller to 180 F and let the wood burn (with all doors closed and no gasification) until it hits this temp and the blower turns off, let the temp drop to the cut in temp and repeat this cycle one more time. Once this cycle has been repeated 2X I use the poker and make sure all the charcoaled wood is nested tightly and then pull the gasification lever and off she goes. It is important to make sure that the first/lower 4-5 pieces of wood are split very small (2-3" in width) to ensure a good bed of coals are created after cycling for 2X in the non-gasification mode.

Hope this helps !

 

[barnartist]

All of that is good North if you are around to do it all. It certainly does help the burn when things can be adjusted on the fly. I think the main goal here is to find a sweet spot so we can "set it and forget it".
I am really liking the ideas in the new topics, probably will bring an end to to this thread. What a run though.

 

[Duetech]

Another fine tune tweak I was inspired to try was elevating the U blocks in the EKO40. (http://www.youtube.com/watch?v=EpbUUGYbv8M). I did that this morning and got some pretty good results. the video clip has the entire structure elevated off the bottom of the secondary chamber but mine is not that elaborate. But what I have I think is forcing a more complete burn in my EKO. By using some standard fire brick as a flat platform I raised my U block 1 1/4" closer to the nozzle. It required a little adjustment on the primary and secondary air but I am getting a better blue flame than I have had and with reduce fan shutter opening I am getting fewer coals building up in the U block channel. The boiler is responsive to temperature changes and climbs quickly up to temps. Will have to see about efficiency.

 

[leaddog]

Another fine tune tweak I was inspired to try was elevating the U blocks in the EKO40. (http://www.youtube.com/watch?v=EpbUUGYbv8M). I did that this morning and got some pretty good results. the video clip has the entire structure elevated off the bottom of the secondary chamber but mine is not that elaborate. But what I have I think is forcing a more complete burn in my EKO. By using some standard fire brick as a flat platform I raised my U block 1 1/4" closer to the nozzle. It required a little adjustment on the primary and secondary air but I am getting a better blue flame than I have had and with reduce fan shutter opening I am getting fewer coals building up in the U block channel. The boiler is responsive to temperature changes and climbs quickly up to temps. Will have to see about efficiency.

It seems like someone else did that but he was having problems with the refactory of the nozzels breaking down. Thought the high heat closer to the bottem and reflecting it back was causeing it. It was mentioned here some were but I don't remember where. it will be interesting to see how you turn out. ((One word of caution about getting these things to hot as you will have to develope a special material to contain as the steel and refactory will melt into a pool, sort of like a nuculer reactor)) Keep up the good work
leaddog

 

[Duetech]

If I remember correctly I think Nofossil was experimenting with firebrick to re-route his fire path and was having problems with standard fire brick being unable to take the heat. This just elevates the U block so I keep the best refractory closest to the flame. The air turbulence in the U block is forcing a very blue flame so I think I am getting the best over-all ignition I have consistently had. Blower shutter is at 1/2" open. Primary is at 6mm and secondary is now avg. at 1 3/4 turns. The flame torches even at these low settings but like I have said the blower really pushes air.

 

[sled_mack]

I thought the idea was to have more volume for the gasses to combust in the lower chamber? Raising the blocks would do just the opposite of that.

My U shaped blocks were crumbling apart so I tried something different this year. I ordered 11.5 inch square blocks that are 2 inches thick from a place that makes industrial refractory. (11 inch square would have been better, I had to grind them to fit. The bottom of the chamber is not flat.) I got six blocks. I place one across the back, wide face facing front. I then place two along each side. The first one in goes tight against the block across the back and the second one goes tight against the first. Looking down from the top would be a U shape, forcing all gasses to the front. The last block sits just inside the door to keep the gasses from eroding the door refractory. I have some regular fireplace firebricks on the bottom to protect the bottom of the chamber.

This has been a huge improvement for me. I get secondary burns much more quickly than I ever did before.

There should be a picture attached to give you and idea of how it goes together. (Or maybe not. I cut the file size down to 63kb, but I still get the error msg saying it's too big and must not exceed 450 kb.)

 

[Duetech]

Hi sled-mack,
This link (http://www.youtube.com/watch?v=EpbUUGYbv8M) was sent to me because of a question I asked in another thread. Notice the height of the bottom of the combustion refractory. There is passage below the combustion refractory for burning gasses to flow through on their way to the heat tubes in the back. That is flow through and flow around design. The fire is very blue, is intense and probably one of the best btu producing mix configurations possible without a vortex. My blower (1/2' open), primary (6mm) and secondary (avg 1 3/4 turns) air settings are lower than the standard recommendations in the newer EKO manual and the fire I am now getting is close to the one in the video clip but with a vortex.

While my U block rested on the bottom in the secondary chamber I was having trouble with turbulence from my secondary air blowing the flame around in random fashion. Placing the U block closer to the nozzle forces the gasses into a vortex before they leave the U block channel and that forces a more complete mix and combustion. For right now I want a long consistent fire to heat my home because I don't have storage and I want to reduce idle time but I also want the cleanest burning fire I can get. It is quite possible that higher air flow requires a larger chamber for combustion to achieve a more complete burn but I also think that the larger flame setting is fitted to the storage concept. I am interested to see what the configuration I have will do where storage is concerned. There is also talk of a new design possibly coming out for the EKO that eliminates the turbulence of the big secondary openings in the refractory by utilizing a larger number of smaller diameter holes. The video clip is also supposed to be one of those new nozzle designs.

As far as your U blocks crumbling apart I am curious if you shut your boiler down for the summer? I run mine for dhw and have had a fire in it almost 24-7 since Thanksgiving week end in 06. I wonder if the down time effects the refractory??? Thanks for the input.

 

[leaddog]

Another fine tune tweak I was inspired to try was elevating the U blocks in the EKO40. (http://www.youtube.com/watch?v=EpbUUGYbv8M). I did that this morning and got some pretty good results. the video clip has the entire structure elevated off the bottom of the secondary chamber but mine is not that elaborate. But what I have I think is forcing a more complete burn in my EKO. By using some standard fire brick as a flat platform I raised my U block 1 1/4" closer to the nozzle. It required a little adjustment on the primary and secondary air but I am getting a better blue flame than I have had and with reduce fan shutter opening I am getting fewer coals building up in the U block channel. The boiler is responsive to temperature changes and climbs quickly up to temps. Will have to see about efficiency.

https://www.hearth.com/talk/threads/13880/ page five shows the bottem of sled_macks refactory that was coming apart with the fire brick added. It took a while to find but I would watch how much I would direct the flame back at the underneath at the nozzels.
leaddog

 

[sled_mack]

Pics of what I have now. (The paper is sticking down because I was just about to light a fire when I remembered to take the pics.)

I do shut down for the summer, so that could have something to do with the U blocks crumbling. Maybe that is related to my issue with the refractory at the top crumbling too? If I can end this winter with enough wood left over, I may burn all summer for DHW. I can go almost a week without a fire with my large storage tank.

In the thread that leaddog linked, the U blocks are on the bottom, but I used fire bricks along the sides of them to channel all gasses to the front, then along the sides to the back. It made an improvement way back then when Zennon told me to try it. However, it made an even bigger improvement this year when I went to the new config.

At Barnartist's encouragement, I finally took off the front cover and adjusted my primaries this weekend. They were full open, now about 10mm. Secondary's were about 6 turns out, now about 2.5. Fan covers are open about 1/2 inch at the wides part of the pie. I basically kept turning down the secondaries till I got a nice gentle flame out the bottom. It still gets secondary burn quickly. It seems to burn much longer per load of wood, but heats the storage tank at almost the same rate per hour. I just restarted the boiler yesterday after being away for a few days, so I'll have a better feeling of how it is working as the week goes on.

One other thing worth noting - with my large storage my boiler sees almost the same conditions every day. Typically, the tank is between 165 and 170 when I restart the boiler, and the timer I use cuts it off when the tank is approaching 180. This is pretty much regardless of outside conditions. The benefit (I think) is that I don't see changes in how my boiler runs due to weather conditions. The only difference is that if it is warm enough I can go to one load a day, but the tank temps are still pretty much the same. So, now I'm curious - for others with large storage, do you have the same experience? Or am I just not noticing subtle differences?

 

[quinn0507]

Why do they recomend the fan opening be 100% for the EKO 40 for the range of wood moisture contents in the manual? This differes from some of the other models.

 

[Duetech]

Probably something to do with the art of manufacturing based on cost effectiveness. It would take a pieces/parts comparison but the likelihood is the blower for the 40 is the same as the one used for the 18 and 25 and that would mean they believe the maximum out put of the blower is more suited to the size of the 40. I wonder if the blowers in Europe run at a slower rpm because the AC runs at 50 cps (cycles per second) rather than the 60 cps here in America. I find for peak efficiency, at some more economical settings, the blower on my EKO40 is over sized. EKO has developed a newer control module that addresses blower speed so it would seem they see the need for a wider settings application than the general set-up recommendations listed in their manual.????????

 

[sdrobertson]

Question for you before I tear down front of stove tomorrow while cleaning everything. I've always had a problem staying in complete gasification. What I've been doing is after stove is up to temp and running well I start to get smoke out the chimney. I would go out to the stove and stir up the wood and it would burn really well for about 5 - 10 minutes and then start to smoke alittle again. In a hour or so I would go back out and stir and again good gasification. What I was thinking was that I couldn't keep hot coals by the nozzles so I would loose gasification. Today I decided to screw around with the secondary air and I went from fully closed to fully opened. Not much difference. I then opened the top and let the smoke clear out like I always do and then stirred the wood. It occurred to me that maybe I was getting to much fuel (smoke) and that maybe the primary's were open to far and letting to much air in the top chamber. I have a fire going so I can't work on the primary's so what I did was open the secondary's all the way and closed down the fan shutters to about a 1/2 inch. Its been about a hour and still in gasification but its not roaring like it does when I first close up the top after stirring the wood. I set the primary's to the manual specs so what I wondering is how much should I close them so that I can start closing my secondary settings and fine tuning? Does any of this make sense or am I spinning my wheels like usual?

Its been almost a month since I started this thread and I thought I'd update it. First of all I need to thank my father and everyone on this site for all of your help. As you read in the first post I was having difficulty keeping my boiler in gasification and I was questioning if I was getting to much fuel. I have made several changes and I think its a combination of all so I'll list them in order: Secondary Covers-I replaced the small disks with metal electrical covers as the screws were located 3/4" to low and even when I closed the secondary's all the way they were still open allot. This seemed to work some and I could change the flame slightly and I was getting better burns. I was still getting smoke out of the chimney and I would loose gasification eventually and create pockets around the nozzles. I closed the primary's and was starting to get better burns again but I still seemed to have to much fuel even when the primary's were closed all the way. I removed my cap off the top of the chimney and this greatly increased my draft which helped "clean" out the bottom chamber and I could turn down my fan air settings to slow down the rate of air going through the stove without losing my stack temp which helped with the pockets around the nozzles. My chimney is 5' of regular black pipe to the ceiling and then 7' of insulated up through the roof so I don't have much draft to begin with but I was still not happy with the ability to fine tune the boiler. The last change was done all together and included changing the metal electrical covers back to the small metal disks and moving the screws up into the proper positions (the electrical covers were heavy and with the flimsy fan cover I think they would bend down and I couldn't control the air to the secondary's very well) and set up the primary's with the bent rods out the side of the stove that was in a post by Dean Zook allowing adjustments to the primary's while the boiler is running. Problems I had was not enough draft, inproper secondary air control(from factory), and not enough really dry wood.
With all of the changes I have made I can happily report that I am extremely happy with the system I have set up. I went from a Central Boiler to this system and my wood consumption was pretty close to half before I started making all of the changes so I can't wait for the rest of the winter to see what I end up with. I was happy with the boiler but frustrated because I knew it could be better. I want to stress to everyone who reads these posts and starts to think that all of the gasifiers are a pain to run and take allot of time to set up and run this is not the case. With all of my problems I had, I was still burning allot less wood and producing allot less smoke than the OWB but these boilers become addicting and its enjoyable to see what can be tweeked here and there to get the best possible burn. It's not mandatory to spend the time but it turns into allot of fun.

Thank You all again for your great posts,
Shannon Robertson

 

[barnartist]

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.

I still am using the electrical box covers on my secondary plates, so I suppose at some point I should just move those screws up as well.

When I squeeze back the air to close to where everyone is trying to run the boiler, like you It all burns well for a while then I lose the flame and gain some smoke. No trouble heating my tanks, but looks like room for improvement here.

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.

 

[stee6043]

I'll add my initial experiences to this thread:

My break-in burn's were completed using "near factory" settings per the manual. I ran 1/2" open on the primaries, 6 turns out on the secondaries, 100% fan power and 100% fan shutter open. I did get decent gasification (very orange flame) but my boiler temps wanted to stay in the 160's most of the time. I did get her up to 190+ for an hour or two over three days. My flue temps held just under 400 degrees.

Before my fourth day of burning I adjusted my primaries down to 9mm, secondaries to 5 turns out, fan speed to 80%, fan shutter opening at 50%. Huge improvement in my ability to maintain 180+ boiler temps. My flue temps also increased to between 425 and 450. I still have a fair amount of orange in the flame but it is blue in the center. I'm still working on tweaking but this was a huge step in the right direction. Great thread

 

[Tony H]

My settings are at 1/4 primaries 2.5 secondaries fan shutter 1 1/4 and the flame is strong and mostly blue and white , thanks to all of the adjusting and testing by you the thing is running better and better.