Lower chamber refractory brick placement on my EKO

[markpee]

My EKO 40 has two curved refractory bricks that "catch" the gasified flame. I've always had them both pushed together and pushed to the back of the lower chamber. I'm wondering if I'm actually blocking the heat from going up the tubes in the rear? Does anyone know the proper placement for the bricks? I also saw a picture of someones bricks that were seperated in between the two. I moved mone at least away from the back of the boiler to see if I can get some more heat out of the unit.

 

[Sizzler]

You want them positioned directly under the nozzle(s) with the "U" forming a tunnel from front to back of the lower chamber.


http://www.youtube.com/watch?v=KYrIo-8CEn4

 

[Duetech]

Ash can build up really quick behind the refractory if pulled away from the back wall and a plugged tube/s can be less effective than one a longer distance away. Forcing the hot gasses through the refractory channel then back around to go up the tubes is probably the most efficient as it forces the hot gasses over more surface area and the temperature drop in the secondary burn chamber is bound to be minimal. Having the the two blocks separated allows the force of the gasses to come in direct contact with the bottom of the boiler refractory insulation. On cold starts that could be stressful to the refractory though that is not likely to be an issue of severe consequence. To me though it just seems to be adding another place to clean ash from.

 

[Duetech]

As far as efficiency is concerned though please keep us posted. We've all shown our desire to get more out of our effort!

 

[markpee]

So heres the update... I moved the bricks forward (away from the back wall) but left them together. I figured out that the 40 has one nozzle, and the bricks should stay together under the nozzle (its longer than the 60 which has 2 nozzles or slots) the 60s bricks should be seperated so they are under each nozzle - 60 owners, correct me if I'm wrong. Anyway, for the last few weeks I couldn't get temps above 150. Mostly this was because the plates that cover my secondary air tubes were out quite far. In fact, talking with cave man I'm certain that they are misaligned from the factory, as I have them closed all the way and am getting GREAT gasification. Even though this was addressed and although I got great heat I couldn't get temps over 170. So at this point I'm thinking that perhaps my 40 is undersized for my house, because if I shut off my zones in the house (I have 12 zones) and allowed the water to only circulate betweek the two boilers I could get wamer water temps. So my last thought was that my water tubes in the back of the boiler were blocked by the refractory brick being pushed back against the wall. With the size of the brick I would say about 70% of the tubes were blocked. So the bottom line is that I moved the bricks so they are centered under the nozzle (a few inches of space in the back and a few inches from the door) and in no time my boiler is at 190 and heating the house so it's nice and toasty! I'm thinking that between opening the surface area of these tubes along with allowing some of the hot flame to travel up there this is the way it's supposed to be. Maybe we all should write the manual for Orlan for the American customer, becasue all of these issues should be there.

I'm finally satisfied that I got this thing tuned in properly, though at some point I will re-visit the plates on the secondary to see how they need to be adjusted. But for now, it works. Without all of the advice from everyone here, I would probably be frustrated and ready to burn oil again!

It takes some time to get these things going, so those who are in the process - don't give up. My first firing was October 26, 2008, and it took until today to get it right - though I'm sure it's not the end of tinkering and fine tuning.

 

[Tony H]

I also have wondered about the placement of these bricks and have moved them around a little while cleaning out ash. I will position mine as you have and see if my results are similar. I have been heating ok and getting gasification but still have some smoke sometimes even when gasification is going strong. Are you describing secondaries or primaries ? I was thinking primarys were the tube covers located behind the fan panel and secondaries are the ones adjusted with the screws on the front lower panel. Just trying to make sure I follow how your adjustments are set.

 

[sdrobertson]

Below is a photo of my older style 60. It has two blocks and one thin curved block that goes in front of the heat exchanger. I have the curved block as far back as I can get it and the two refractory blocks directly under the nozzles. Is anyone setting theirs up differently? I think the newer style 60's don't have the thin curved piece and I'm wondering if without it if I would send the heat to the exchanger more evenly. The way its now, the heat has to travel around the curved piece and up the sides which maybe would only send the hottest exhaust up the outside tubes and miss the middle of the heat exchanger. When I got this stove, I figured that this curve piece was to slow down the exhaust by forcing it to go around this, but know I'm wondering if it would be better going directly out.

 

[taxidermist]

Shannon,

What about putting that curved block next to the door to direct the heat back twards the exchanger? I just watched that youtube video and his curved block was in the back also???

Rob

 

[sdrobertson]

That might be where its supposed to go - I'm shutting down tomorrow to clean the tubes so I'll try moving it and see what happens. Big surprise but the manual states nothing on this. I can't find it now, but some time ago Nofossil posted something about these when he first started making his own refractory blocks and creating a longer fire path. I guess the only real way to know is to move it and see what happens.

 

[markpee]

I also have wondered about the placement of these bricks and have moved them around a little while cleaning out ash. I will position mine as you have and see if my results are similar. I have been heating ok and getting gasification but still have some smoke sometimes even when gasification is going strong. Are you describing secondaries or primaries ? I was thinking primarys were the tube covers located behind the fan panel and secondaries are the ones adjusted with the screws on the front lower panel. Just trying to make sure I follow how your adjustments are set.

Ummm...arent those tha you describe the same? When I took the fan panel off, the round plates that cover the tubes are the same same as the screws attached to the lower panel. Therefore, in order to adjust them you simply move the screws. Right? Don't forget, I have the 40 - those with other models may have a different setup. As far as I know the only adjustments I can make are the fan opening and the tube covers.

 

[verne]

the primarys are behind the front cover at the top with steel plates that can slide when you loosen a bolt. the 40 is about 1/2 ". the secondarys are what can be screwed in and out from the front below the fan. the 40 is about 3.5 turn out from closed. the fan shutteris the fan shutter, the manual states 100% open ,alltough I do well with about 1 1/4"- 1 1/2" open.I was told to put the curved refractory all the way to the back , but that is interesting how you can get much higher temps .I can heat my 1000 gal tank to 190 but it does take time depending on my heat load

 

[markpee]

If you look at this link to Cozy Heat's website, you can see Orlans "heat flow" which makes it look like the hot gas should flow behind the refractory brick, hence, we should move the brick away from the back wall.

http://www.cozyheat.net/ekodiagram.htm

 

[Tony H]

I moved mine and have not seen much change yet, it does seems to be running strong with good gasification and water temp is unchanged. Will continue to run like this and see if it helps any with the gasification going well but still putting out too much smoke / improved consistency. Every little bit helps.
Has anyone else noticed the boiler seems to run better and longer when its colder out ? Has been colder the last week 2F last night and many of the burns ( but not all ) went very well and long , still had 1/3 load left after 8 hours.

 

[markpee]

I moved mine and have not seen much change yet, it does seems to be running strong with good gasification and water temp is unchanged. Will continue to run like this and see if it helps any with the gasification going well but still putting out too much smoke / improved consistency. Every little bit helps.
Has anyone else noticed the boiler seems to run better and longer when its colder out ? Has been colder the last week 2F last night and many of the burns ( but not all ) went very well and long , still had 1/3 load left after 8 hours.

Give it a while to heat up - be sure your tubes aren't clogged like mine were. I vacuumed them out. As for smoke - I have none. Not sure why you do. It is 19 degrees here in NY with 30-40 MPH winds and my house is a lovely 72 degrees.....don't think this would have been possible without the adjustments I made.

 

[rickh1001]

markpee

I wonder if the placement isn't designed to protect the steel on the back of the HX's from the fireblast of the gasification chamber? Sometimes mine seems dull, but when it is in full blown gasification mode, it is a fearsome thing to behold. There is some intense heat going on down there! In another thread, a list member found his refractory damaged when he moved it only a little closer to the flames by putting firebrick under it. Not to say there isn't an optimal arrangement, but I would work with the distributor and your dealer, and go a little slowly in this area. It would be a shame to find your HX tubes pushing more heat, but damaged after a year of operation at too high a temp. The idea of ideal arrangement is worth going after, but in my opinion, in conjunction with your dealer.

 

[Duetech]

If you look at this link to Cozy Heat's website, you can see Orlans "heat flow" which makes it look like the hot gas should flow behind the refractory brick, hence, we should move the brick away from the back wall.

http://www.cozyheat.net/ekodiagram.htm

Good eye Mark. I moved mine to see if it would make a difference. Still my major concern is cleaning the area behind the refractory. The amount of ash that can accumulate behind the blocks is apt to be greater. My optimism, though, is riding high because of the adjustments that I have recently been going through leaning the burn and lengthening the burn time. The restricted air flow will/should reduce excessive wind velocity in the secondary chamber and the excess pressure it creates in the primary chamber. I haven't run long enough with the new settings to get a general feel for the set up but I know the flame is smaller and has more blue in it . I'll have to wait and see if there is a problematic ash build up on the back side of the blocks and if it's too much trouble to mess with compared to any improvement of operation.

 

[markpee]

If you look at this link to Cozy Heat's website, you can see Orlans "heat flow" which makes it look like the hot gas should flow behind the refractory brick, hence, we should move the brick away from the back wall.

http://www.cozyheat.net/ekodiagram.htm

Good eye Mark. I moved mine to see if it would make a difference. Still my major concern is cleaning the area behind the refractory. The amount of ash that can accumulate behind the blocks is apt to be greater. My optimism, though, is riding high because of the adjustments that I have recently been going through leaning the burn and lengthening the burn time. The restricted air flow will/should reduce excessive wind velocity in the secondary chamber and the excess pressure it creates in the primary chamber. I haven't run long enough with the new settings to get a general feel for the set up but I know the flame is smaller and has more blue in it . I'll have to wait and see if there is a problematic ash build up on the back side of the blocks and if it's too much trouble to mess with compared to any improvement of operation.

Cave Man - one thing I've noticed is that now that I am burning hotter, I have almost no ash - just some very fine white powder. This may help your worries a little. Don't be afraid to use a shop vac - just be sure the dust is cool, and dump it in a fire proof container outside when done. They also sell furnace vacuums made for cleaning furnaces.

 

[Duetech]

markpee,
Where would a person get one of those furnace vacuums? My shopvac is plastic and would certainly love to embrace a few warm coals and there are times I would love to let it.

 

[markpee]

Probably ebay is your best bet. I found one for you...

(broken link removed to http://cgi.ebay.com/Wood-pellet-stove-fireplace-furnace-ash-vacuum-cleaner_W0QQitemZ400006484025QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116)

 

[Duetech]

Thanks Mark

 

[markpee]

markpee

I wonder if the placement isn't designed to protect the steel on the back of the HX's from the fireblast of the gasification chamber? Sometimes mine seems dull, but when it is in full blown gasification mode, it is a fearsome thing to behold. There is some intense heat going on down there! In another thread, a list member found his refractory damaged when he moved it only a little closer to the flames by putting firebrick under it. Not to say there isn't an optimal arrangement, but I would work with the distributor and your dealer, and go a little slowly in this area. It would be a shame to find your HX tubes pushing more heat, but damaged after a year of operation at too high a temp. The idea of ideal arrangement is worth going after, but in my opinion, in conjunction with your dealer.

I wrote to Dave at Cozy Heat regarding the issue, here is his response: "Your exactly right, you need to leave some space at the rear for the heat to flow."