eko fan adjust

[barnartist]

It would be great to have the fans on the eko respond to stack temp as well as water somehow. For me since I have been starting from scratch fires now, I find I need the openings on the fan about half open, but after a good fire is gasifying, this is too open. I monitered my stack today with a wireless meat therm. and got up to 500 on the stack, where if I could "tease" the fans to slow down maybe- keep a nice 300-350 stack, I can stretch out a burn longer. What do you guys think?
Maybe this is an old topic, don't see it handy.
Lets hear it Nofo.

 

[Eric Johnson]

That sounds to me like a lot of work for not much gain, if any. I think stack temps are interesting to watch, but my understanding is that high stack temps result from diminished heat transfer in the tubes, and not necessarily too much air. Mine are all over the board, too. Occasionally they get as high as 500 or 600, but generally hang in the 300-350 range.

I'm surprised that you have to open the sliders on your blowers to achieve good gasification. I pretty much leave mine alone, though I do open them up a bit when it's really cold outside. I suspect that might have more to do with your 6" chimney and resulting diminished draft, which can also contribute to diminished heat transfer in the tubes.

 

[barnartist]

Maybe, Eric, but when I keep a continuous fire I can leave them open about a half inch. On start up from cold it helps to open them up more. To me, anything above 350 400 means too much heat loss. Maybe the water speed should be faster then, not sure. Maybe it doesnt matter as much as I think. The air goes through the exchanger tubes too fast to transfer enough heat and right up the chimney the way I see it. I can find a happy medium I guess as far as the openings go.
This reminds me, I leave my fan cover off all the time. One for fan adjust, and two they vibrate so loud-AKA noisy.

 

[Eric Johnson]

I've forgotten, barnartist, do you have turbulators in your tubes? (Kind of a personal question, I know).

 

[barnartist]

Yup. Ones I made. I wonder how tht chain idea works?
I think mine are real similar to the new model. Just no handle.

 

[tuolumne]

Please excuse the obvious hijack...I have an EKO 40 in the works with a 1000 gallon propane tank. This is the first I've read of deliberatly creating turbulance. What was your modification, and how effective is it. The supplier indicated that the laddomat pump was insufficient to circulate the water when this boiler is going all out. (13 gpm if I remember correctly) At what gpm are you circulating water through the boiler, and do you feel this is sufficient based on the stack temps you're getting? This does stay on topic, right? Thanks.

 

[Eric Johnson]

We're talking about turbulators in the heat exchanger tubes. On most boilers, they're strips of steel twisted to form a spiral pattern. They interrupt the flow of hot gas though the tubes, resulting in longer dwell time for the gas and greater heat transfer. They lower stack temps as a result. On the newer EKOs, they double as hx tube cleaners, as you can move them up and down in the tubes with a lever, knocking the soot and other crud off the tube walls and back down into the ashpit. Here's a photo of the tops of the turbulators in my EKO 60, as seen from the chimney connector.

 

[barnartist]

Eric, was that pic taken brand new im sure?
I wish I could make a lever like that so I didnt have to open it up as much back there.

Its good to know the laddomat is 13 gpm. Never really knew for sure. I know a guy that runs it all from that pump alone.

 

[Eric Johnson]

Yep, right off the boat.

I'd think a retrofit wouldn't be that hard to engineer. Nofossil is talking about something like that, but knowing him, it will be something he and his mad scientist/fabricator brother conjure up out of scrap steel. I bet Zenon could get you the stock hardware and some instructions for putting it together. Some welding but as you can see, not much. That's a wall of wood in my barn that you can see through the open firebox door.

 

[barnartist]

my wall of wood has been reduced to a bunker.
How many cords you ran through thus far Eric?

 

[Eric Johnson]

Probably 5. The stuff in the pic is long gone. I just wrapped up insulating all my runs through non-heated spaces over the holidays, so I should burn a lot less per week from here on out, but I'll probably exceed the 10 cords I was planning on by a cord or two. Getting the tank going should help a lot, too. Now I just turn up the heat when the thing threatens to idle. But I'm afraid that if I get the tank going and turn the room stats down to 70 or 72, my girls are going to go "cold turkey," and I'd rather burn extra wood than deal with two ticked off women.

The bottom line is that my wife really likes a warm house and red hot DHW. And I really like to cut wood. Match made in heaven.

 

[barnartist]

I forgot you had no storage. Im still wondering if keeping from going idle is overrated- as far as wood use.
Im about the same as you- close to 5 cords.
I hate to add more storage and not gain much for the effort. And lose more Garage space. Wish I could hear some real results, some concrete evidence.
I have 3 gals in the house, but only one old enough to turn up the thermostat when im not looking. I keep it about 75 in here. Like you.

 

[Nofossil]

I forgot you had no storage. Im still wondering if keeping from going idle is overrated- as far as wood use.
Im about the same as you- close to 5 cords.
I hate to add more storage and not gain much for the effort. And lose more Garage space. Wish I could hear some real results, some concrete evidence.
I have 3 gals in the house, but only one old enough to turn up the thermostat when im not looking. I keep it about 75 in here. Like you.

I've posted my wood consumption before and after storage in another thread - basically, no difference for me. The benefits of wood in my case is much more even house temps, never running out of hot water, fewer fires (skip days), and more flexibility about when to build fires.

 

[Nofossil]

It would be great to have the fans on the eko respond to stack temp as well as water somehow. For me since I have been starting from scratch fires now, I find I need the openings on the fan about half open, but after a good fire is gasifying, this is too open. I monitered my stack today with a wireless meat therm. and got up to 500 on the stack, where if I could "tease" the fans to slow down maybe- keep a nice 300-350 stack, I can stretch out a burn longer. What do you guys think?
Maybe this is an old topic, don't see it handy.
Lets hear it Nofo.

I'd like to do that to control output. In effect the EKO controller does it by idling. I'd prefer to slow the fan down so that the boiler output matches the heat load better. Even when heating the tank, the output of the boiler exceeds the heat load when the tank is getting hot.

 

[barnartist]

Ya! If I could get those fans to crawl I think it would be great. The fan adjust on the cpu doesnt seem to do anything.

 

[wdc1160]

I’d like to do that to control output. In effect the EKO controller does it by idling. I’d prefer to slow the fan down so that the boiler output matches the heat load better. Even when heating the tank, the output of the boiler exceeds the heat load when the tank is getting hot.

I am surprised you would think of changing the fan to address the excess heat load absorbtion problem. Any other methods your entertaining?

 

[Nofossil]

I am surprised you would think of changing the fan to address the excess heat load absorbtion problem. Any other methods your entertaining?

I juggle loads as much as I can. When everything is cold, I have no problem using the whole output of the boiler, and I'll cycle low priority loads (DHW superheat, hot tub, storage) on and off to match the heat output and maintain target outlet temperature. When th house, hot tub, and DHW don't need any more heat, storage is all I have left. As storage approaches 180, I can dump less and less BTU/hr into it, and the boiler will hit 180 and the EKO will kill the fan until it drops to about 172.

I don't know any other way to throttle it other than slowing down the fan. The EKO controller does that, but not enough (or not soon enough).

Good basic question: Given the geometry and sizing of the EKO, is there a burn rate that yields optimum efficiency? If not, how much efficiency do you lose running at a constant 60,000 BTU/hr instead of 80,000 BTU/hr? All the efficiency discussions that I've seen talk about the efficiency loss from idling, not from running at a lower but still gasifying fan speed.

 

[barnartist]

You can do it Fossil. Your right it needs one more gear lower, like how a light dimmer works-
So if you are certain that much is lost by going Idle- I lose allot. Maybe I'll try smaller loads of wood until I can get more storage. I wonder how I can figure a ballpark on how much works for me, or if I make extra storage tanks that I can shut down during really cold days.
Has to be a way to slow the fans. You guys can figure it out.

 

[Eric Johnson]

I looked over the manual for the new EKO controller, and there's no mention that I can find (kind of hard to follow the translation sometimes) of doing what you guys are suggesting. I thought there might be, since it sounds like a logical upgrade that a new controller might have. Which begs the question: What makes you think it will work the way you want it to? Do you think it's possible that slowing the airflow at lower temps might adversely affect gasification and/or efficiency?

BTW, the new controller allows you to set the temp as high as 195 degrees F., and it reads out in F, too. I've heard several times that higher temps actually increase efficiency, but European regs prohibit operation in excess of 80 C. (175 F).

Did you ever try blocking one of the nozzles, barnartist?

 

[barnartist]

I tried it Eric, but didn't like it. Maybe its an acquired taste. I think I need a bigger piece of refactory concrete. I tried a piece of steel, but would you believe that it found enough air to gasify around it?
I already heat my water to 195 by teasing the cpu's probe with some insulation. The fact is as I watch my bottom chamber, and as the burn goes on, I lose that really big flame and it turns to just a glow anyway. I think getting the fan to pump just a small amount of air to keep those coals hot instead of a shut down. I dinno-just me.

 

[GibsonGuy]

To block a nozzle, I just stuffed fiberglass insulation in it and all seems to be going well. There is absolutely no leakage of smoke in the lower chamber this way and I think it does burn better. We are expecting a very cold weekend, so I'll just push the insulation thru to the lower chamber and remove it. I had some firebrick, but it was too large and I couldn't find my diamond blade, so I worked with what I had.

As for the unit not being the most efficient at times. I love the way the EKO shines when new wood is added. It really goes into hyper mode when there is smoke when fresh wood is added to an existing fire. To me, that smoke in all other units is just going up the chimney and polluting the air. With the EKO, it appears to be achieving a maximum performance and minimal pollution.