EKO self opening damper

[Tony H]

The first time I thought well maybe I could have left it open the second time I was standing right there. The boiler was just filled about 3/4 full with alot of cut down pallet wood and I guess the wood gas was built up then the fan kicked on with a burst of air then a bang and the damper flew partway open . Kind of scary if it kicked open at night then ran and overheated.
It's still not too cold so I want to use some more of the second rate wood so took and connected a vice grip to the handle so it can't push open. Anyone else ever have this happen?

 

[trehugr]

Oh yes, and it is disconcerting to say the least. The problem has to do with not enough draft. It was recomended by my supplier to instal a draft inducer in the stack and wire it parallel with the EKO fan. This should solve that problem.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_21928_21928

 

[Jim Post]

Is this the barometric damper on your flue pipe?...

I had alot of trouble last season with my barometric damper staying open....for a long time I ran my tarm with a block in place that prevented the damper from opening fully and helped it back to the closed position if conditions caused it to open. Towards the end of the season I covered it with a couple of layers of heavy aluminum foil wired in place.

This year I am considering blocking it closed with an chimney end cap.

What is the purpose of a barometric damper? Are they required for a proper set-up?

Thanks,
jp

 

[Duetech]

The first time I thought well maybe I could have left it open the second time I was standing right there. The boiler was just filled about 3/4 full with alot of cut down pallet wood and I guess the wood gas was built up then the fan kicked on with a burst of air then a bang and the damper flew partway open . Kind of scary if it kicked open at night then ran and overheated.
It's still not too cold so I want to use some more of the second rate wood so took and connected a vice grip to the handle so it can't push open. Anyone else ever have this happen?

Is yours the EKO 40 Super or Regular? The regular comes with a heat exchanger tube cleaner tool. The Super has a long shiny handle on the left side that controls a set of cleaners that come installed in the tubes that you cycle to clean the tubes. I installed the handle so that it points downward instead of up. Now when I cycle the handle in the right direction if the flap (primary combustion chamber bypass) is open the handle for the cleaner will push the flap closed. It's not really a lock but it helps. I don't have storage so I get a lot of idle time and cool stack temperature. Cool stack/draft temps slow the draft way down and that can cause the puffing that blew your flap open. Poor air mix can cause the puffing too so see your manual to make sure the mix is correct.
If you have the 40 regular then a spring under pulling tension hooked over the closed upper combustion door handle and the closed bypass flap handle will automatically re-close the flap in case of puffing. You will just have to unhook the spring from the flap handle when you want to open the upper chamber door.
Another note on the Super. With the tube cleaner handle positioned to keep the bypass damper closed it is very difficult to open the flap (mine won't open at all) so it is best to reposition the tube cleaner handle first or you might think the flap is stuck and they do get stuck at times. Cave2k

 

[Tony H]

Trehugr- Thanks for the link , wonder if they have a different model for use with double wall insulated pipe or maybe just add the chimney (I was planning to add 2' to help the draft )
Olpotosi - no bio damper on this unit
Cave2k- I have the super with the built in cleaner and mine came installed with the handle pointing downward. I will have to check where the handle needs to sit to help hold it closed. I have been running about a month and this has only happened when I used alot of pallet wood in it, I do not have any storage so it does idle and more often the flap has stuck closed and I reversed the upper door handle so I can open the door and push it open with the poker. I am planning to add another 2' of chimney because it doesn't draft well enough when the upper door is open to load and there is still some wood remaining.
I was thinking my air mix was pretty close because I am getting fast and good gasification . It's good to hear the issue appears to be what I thought and it should be better when I add the chimney because it sure scared the crap out of me when I went out and the temp was 90c at the thermo was set at 75c .

Thanks

 

[hkobus]

The first time I thought well maybe I could have left it open the second time I was standing right there. The boiler was just filled about 3/4 full with alot of cut down pallet wood and I guess the wood gas was built up then the fan kicked on with a burst of air then a bang and the damper flew partway open . Kind of scary if it kicked open at night then ran and overheated.
It's still not too cold so I want to use some more of the second rate wood so took and connected a vice grip to the handle so it can't push open. Anyone else ever have this happen?

With cold weather I actually use my hard and large wood first, for the simple reason that it will produce less gas. What happened to you used to happens a lot to me too, until I figured it out. When the boiler goes to idle or just produces more gas than it can burn, it will at times "explode" in the upper chamber with the result you described.
I don't think it is safe to block this, you could damage other parts like the fan. (it has a little one-way flap mounted inside the front panel)
I would spend some time mixing and matching wood size, quality and quantity to prevent this and get more out of the burn.

 

[Tony H]

Hogstroker - good point, I don't want to damage anything. I wonder if the purge setting could be adjust to also help with this problem. One reason I would like to find a solution that allows me to use the pallet wood is that I have a bunch of it and access to more. The last couple of loads I adjusted the mix like you said and it seems to be running fine.
The future addition of some storage would also help by reducing the idle time of the boiler.

 

[hkobus]

Tony,

Just keep experimenting, you may want to "bundle" or tightly stack the wood to reduce the space, adding some wet wood can also help at times. Pallet wood is very dry.

Henk.

 

[Duetech]

With cold weather I actually use my hard and large wood first, for the simple reason that it will produce less gas. What happened to you used to happens a lot to me too, until I figured it out. When the boiler goes to idle or just produces more gas than it can burn, it will at times "explode" in the upper chamber with the result you described.
I don't think it is safe to block this, you could damage other parts like the fan. (it has a little one-way flap mounted inside the front panel)
I would spend some time mixing and matching wood size, quality and quantity to prevent this and get more out of the burn.[/quote]

A sticky valve is the same thing as a partially blocked bypass flap or worse. The spring loaded flap handle would automatically return the flap handle to the closed position and prevent the fear of the boiler over heating from a partially open bypass flap. It appears the manufacturer was aware of this before they shipped the boilers and placed the one-way flap for the blower to protect the blower. Perhaps I should have made the statement clearer by saying that on the Super 40 the tube cleaner in the proper position only prevents the bypass from fully opening not "won't open at all" as the over center spring for the bypass handle automatically closes the bypass when the stove "explodes" the gasses in the upper chamber when the tube cleaner prevents full motion of the bypass flap. I did say "it doesn't lock the bypass" in position. Sorry for the confusion...Cave2k

 

[jebatty]

JP with Tarm Solo Plus 30 -- Is this the barometric damper on your flue pipe?…This year I am considering blocking it closed with an chimney end cap....What is the purpose of a barometric damper? Are they required for a proper set-up?

I doubt there should be a need for a barometric damper on the Tarm 30 (or 40 which I have). I had some early-on over draft problems last year and put one on in an attempt to solve the problems. It caused more problems that it solved. Now it is screwed shut.

Search "barometric damper" and you will find lots of info, most indicating no need to use.

If you have an overdraft problem, realize that the draft fan damper can be adjusted all the way to full close (which you don't want to do), so you have lots of ability to control draft. I need more draft when it is relatively warm outside (30 and up), so I used to open the adjustment some to allow more air, and vice versa when it is colder. Now I found a middle spot and also installed a motor speed control on the draft fan so I can slow it down when less draft needed, full speed when more draft is needed. No further interim adjustment of the draft fan damper is needed for optimum operation.

 

[Jim Post]

Well I capped off my barometric damper on Friday night ....things seem to running fine without it. I only have about 15 feet of chimney so overdraft should not ever be a problem.

thanks for info.
jp