Under the Hood

[Eric Johnson]

Here's what the air intake system looks like on an EKO 60.

The yellow air adjustment knobs are a modification. Just two wire nuts screwed and glued onto the ends of the adjustment screws. It's a lot easier to play with the air adjustment if you can grab it with your fingers, instead of fiddling around with a screwdriver.

Note that there's nothing fancy or sophisticated here. The two sliding plates in the upper corners allow air into the firebox, I believe. The air supply to the nozzles is delivered through the round pipes. It is regulated by the steel disks, which are adjusted with the (now knobs on the) threaded rods. Then there are the adjustable baffles on the blowers.

I believe the EKO 25 and 40 have one nozzle and one blower. The 60 has two of each, and I believe the 80 does as well, though it might have 3.

 

[Tony H]

The little "manual" that can with mine doesn't mention these adjustment knobs, is there another document that goes into more detail on the operation and installation of everything?

 

[Eric Johnson]

No, that's one reason I made this post. The manual is woefully lacking in useful information. It does remind you to properly dispose of the boiler when it dies, however.

The round air adjustments should start open 3.5 turns and then you can fine tune it from there.

I got most of my installation information from Dave at cozyheat. If you have any questions, just ask. There are a number of us around here who have installed EKOs and got them running.

 

[Nofossil]

I like the knobs - excellent idea. I'm looking forward to some data on what the effects are if these are too far in or not far enough - what are the observable symptoms?

I'm adding an oxygen sensor to mine, probably later this month. Should give us more insight as to just exactly what's going on.

 

[Eric Johnson]

Now that I have the knobs, I'm playing with it. I'll let you know.

 

[hkobus]

Thanks Eric,

I do like the knobs as well. I was about to pull the shield of soon. Have you seen some leakage around the cords there, I have seen smoke puffing out in the past and there are some smoke tracks visible on the green. I wonder if this is from before I installed my draft controler, what a difference :smirk: . I hope to fix this with high temp silicone soon.

 

[TCaldwell]

nofossil, you mentioned a oxygen sensor, is this to monitor combustion effiency? can you elaborate, i am all ears, thanks tom

 

[Eric Johnson]

No, no leakage around the blower mounting plate. You have to be careful to put the screws in with fairly even pressure.

 

[Nofossil]

nofossil, you mentioned a oxygen sensor, is this to monitor combustion effiency? can you elaborate, i am all ears, thanks tom

*** Warning *** Thread hijack alert!

You got it - I think the problem is the same for cars and boilers. You want to make sure that you have enough oxygen. In the case of a woodstove, and extra is wasted energy. An automotive oxygen sensor should work fine, although I don't know about sensor life. I have to fab up a bracket to hold it in the hot gas stream, since they need to be pretty hot to work. I've got a data acquisition / control system with spare channels sitting right next to the boiler. I'll post data as soon as I get a chance to set it up.

 

[Eric Johnson]

Careful, guys. You're gonna scare the newbs away with talk like that!

Fascinating, actually. Are you saying, nofossil, that too much air wastes energy because it sends too much heat up the stack? Is there an analogy to an engine, such as lean vs rich?

 

[leaddog]

Had a major problem today with my air nozzels on my eko80. The secondary air nozzel pipes started to back out and was pushing against the secondary adjustments so hard that it was warping the sheetmetal. I pulled the cover off and the tack welds were bad. I called Dave at Cozy Heat and he got right on it with Zennon and got back to me right away. They said that they had never had it happen before but I could pound the pipe back and retack it. Thats what I did. When they tack welded it they had a cold weld so it didn't weld. I think that with the heating and contracting of the pipe that the pipe worked out. There wasn't any damage and things look good now. The eko80 is quite a bit longer so those pipes are longer also so there is more thermo-expansion and more tension from the fire brick but they went back right were it was suposed to. Now I have to fine tune the air again.
Just a heads up in case you see your cover being pushed out or your secondary air woun't stay tuned.
Leaddog

 

[Nofossil]

Had a major problem today with my air nozzels on my eko80. The secondary air nozzel pipes started to back out and was pushing against the secondary adjustments so hard that it was warping the sheetmetal. I pulled the cover off and the tack welds were bad. I called Dave at Cozy Heat and he got right on it with Zennon and got back to me right away. They said that they had never had it happen before but I could pound the pipe back and retack it. Thats what I did. When they tack welded it they had a cold weld so it didn't weld. I think that with the heating and contracting of the pipe that the pipe worked out. There wasn't any damage and things look good now. The eko80 is quite a bit longer so those pipes are longer also so there is more thermo-expansion and more tension from the fire brick but they went back right were it was suposed to. Now I have to fine tune the air again.
Just a heads up in case you see your cover being pushed out or your secondary air woun't stay tuned.
Leaddog

When I went over my EKO, I was not impressed by the fit and finish of the welds. All of mine were solid, though, even if not pretty. I've got a MIG welder next door if I need it.

 

[TCaldwell]

nofossil,what does this data aquasition control do, sounds sort of like a permanantly mounted combustion analizer , i have not been able to find one , will a oxygen sensor alone supply enough info? could you walk me through your thoughts . thanks tom

 

[leaddog]

I have NOT been unhappy with the fit and finish and the welds seem to be good EXCEPT this one case. They just put a small tack to hold this pipe inplace and it was too small and a cold weld. I have a mig welder also and it is easy to make a cold tack-weld with one Thats why I used my buzz-box to fix it.
Then again I do think that the air adj setup is a weak point. The cover is light sheet metal and you have the fans hanging on it. The cover with the adj screws can flex alot where the screws go so I can see where you can be hard to get a consistant adj. I'm THINKING about making something so you can adj it easier. Stay tuned.
leaddog

 

[Eric Johnson]

Look at the left tube in my photo, leaddog. It's always been like that, but it doesn't look right to me. Is that what yours did?

 

[leaddog]

Eric----------------- I was just looking at your pic of your air pipes and it looks like the left
pipe of yours is moving out. It shows the marks of movement like mine did. You might want to check it.
leaddog

 

[Nofossil]

Careful, guys. You're gonna scare the newbs away with talk like that!

Fascinating, actually. Are you saying, nofossil, that too much air wastes energy because it sends too much heat up the stack? Is there an analogy to an engine, such as lean vs rich?

I'm thinking two things here (that's my limit, by the way). First, any extra air is wasted heat up the chimney not to mention the energy to run the blower. Second, I think the blower pushes too much air during startup and when the fire is dying out. Too much air prevents good secondary burn. In engines, lean means too hot and can burn valves. I'm not as worried about that, but too much air diffuses the flame and makes it hard to maintain secondary combustion.

nofossil,what does this data aquasition control do, sounds sort of like a permanantly mounted combustion analizer , i have not been able to find one , will a oxygen sensor alone supply enough info? could you walk me through your thoughts . thanks tom

It's a long story. I built my own homebrew controller that monitors and controls my whole system. There's lots of detail on my site - link is in my signature below. Essentially, it sits on top of the oil boiler and wood boiler controllers and tricks them as needed to get the desired results. It can control circulators and zone valves directly. I'm thinking of giving it the ability to override the EKO controller as far as fan speed is concerned.

 

[leaddog]

Look at the left tube in my photo, leaddog. It's always been like that, but it doesn't look right to me. Is that what yours did?

You were fast. Yes that is what mine did only it moved out over a in. and pushed so hard it jamed the air adj back and bent the cover. If you look you can see where they welded it. All you have to do is tap it back and re-weld it. Maybe this is a problem that everyone should watch. If the weld isn't holding it all that is holding it from moving is the friction of the cement. You might want to pass the info on to Dave and zennon also
leaddog

 

[Eric Johnson]

Bingo, 'dog. Same deal with mine. I just went out and checked it and sure enough, the tack weld broke off and the tube was walking forward. I tapped it back into place and screwed a couple of sheet metal screws into the gap to hold it for now. I'll have to get someone over here to weld it up. Actually, might as well have them weld them both up while we're at it. I'll let Dave know, since I'll need some reimbursement for the welding. Wish I had a rig and the knowledge to do it, but I don't.