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[Bill G]

Hey Guys,

    I'm really easy on dropping (placing) my firewood in box.  Take great care in cleaning out around the nozzle opening and yet have lots of chips/chunks spalded off of nozzle opening.  I hope repair/replacment of the nozzle ain't going to be to difficult, but probably will need to be adressed at end of burning season. 

    Wish to thank Marty for his guidance in cleaning out air/blower box in back of furnace!  Found lots a creosote and spent the time cleaning out and now, she runs clean!  Big difference in smokeless performance.  Going to need a box of the self tapping screws that hold the cover in place.  That creosote already began eating the exposed threads off them, that stick into the airbox.  Stainless self tappers seem like an idea. 

    Also notice the air covers on the 1/4 20 all-thread rods won't be around forever, as the rust from creosote assault will eat them up in short order.  1/4 20 all-threads permanently coated with the hardest dried creosote and adjustment out anymore, a thing of the past.  Re-design coming up after the burn season.   

    Tried wire brush and not worth the effort to get clean.  Will just put a little time in the machine shop.

    Maintenance intensive, is starting to come to mind here.  ML-36 thoughts slowly creeping into my brain.  Wonder if I should have went with tried and true?  Would have been too easy though.

[martyinmi]

Bill,
   We all put zinc coated self tapping body screws back in ours. We coated them with Liquid Wrench white lithium grease(10.25 oz. can-Auto Zone), as well as the elongated slot for the secondary air, and the bushings that the actuator shaft runs in. Creosote will not stick to that stuff. I should have told you the other day when we talked, but my memory-along with other things- might be failing a bit
   I did more testing this past weekend to see if my modifications were legitimate. So far, so good. Close to 15% less so far. I'm experimenting with even lower stack temps as I type. I'll keep ya posted  

[coolidge]

There is a replacement nozzle, but you have to cut it in, that sounds like fun.  I lubed everything in that airbox with never seez as i had too replace the upper air rod this past year. No problems now with it moving.

[Bill G]

Thanks for your replys, thus far. 

Marty, yeah, I can see lots of lithium grease on the threads and any moving parts in the airbox.  Going to let it ride for a bit until spring, then complete re-do, "Bill's style".  Sure was on bloody mess! 
     Seems like most anything needs a bit of tweaking these days.  Glad to have my shop and enough no-how to make it right.  When I get around to it, after heating season, I'll be sure to compare notes w/you.  Those mild steel discs, welded on the all-thread, now those ought to be rotted right off in short order.  Going way thicker and 304ss.  Push/pull adjustment w/sealed inside. 

Coolidge,
    Sounds like tons a fun with die grinder if thats the case for nozzle repair.   Wonder how a welded up nozzle would hold up?  Cut out refractory and fab up a stainless job?  Just drop in and easier to replace.  I figure a refractory cement fix would be in the same condition every spring...

     No complaints on the heat output, etc., but maintenance excessive! 

          As the ol'man used to say, "What's on your mind, just say it already!!"  OK, I would have been better pleased with ml30 or ml36.  Sure, I was am happy for no heat bill, but I see lots a maintenance w/opt 250.  Too late now. 
          I do realize Pennsylvania wants us to have epa phase II jobbers, but, maybe the epa could come out every 10-14 days and scrubb that bad boy up for me!  Pain in the N***s!  To C/S/S even 3 more cord a year would be enjoyable work, as compared to cleaning/preventive maintenance I'm starting to see after just 4 1/2 mo of burning. 

          YES, my wood is dry, clean, the best quality that can be had around here!  All hardwoods, down, C/S/S for 18-24mo. 

     

[tinner]

curious about this.

How is the crud backing up into the air box? On low fire (no fan) is there a bypass around the reaction chamber? Or is everything still supposed to go down through it? That is about the only way that I can see it getting that far back. I sure would like to see a pic of the inside of that box if you take the cover off again.
: )

Thanks!

P.S. Stainless sheet metal type screws are only coated with st. st. IIRC
Best to coat them with some thing.

edited to add: what kind of dimensions does that nozzle have? Is it just cast into the cement ie no metal.

[Bill G]

Hey Tinner,

      Mild winter inducing lots of idle time for the furnace.  The creosote gathers in liquid form and can/does free-flow through the air channel to the air box.  The only place smoke and gases can go during a burn is straight down through the refractory nozzle, into the secondary burn chamber.  The refractory nozzle gets red hot during a burn and thus the problem of spalding/cracking of nozzle.

     I can't measure the nozzle opening now, but will wager a guess.  It is a slot located in the firebox floor, running fr. to bk.  Roughly 2" wide by 8-9" long.  Cast in refractory floor.

     With the mild weather, it simply doesn't matter how well seasoned your firewood is.  Long idle times produce a degree of creosote.

     Will coat everything in air box w/the liquid wrench lithium grease, as per Marty, next time I visit the airbox.  Thanks for the heads up on new screws, they'll get the grease too.

     I only load very sparingly during mild weather and this seems to help.   

[tinner]

Thanks!

 

[coolidge]

What do you guys think about a round nozzle instead of the "slot" type? I am going to get some brick and give it a try.

[Bill G]

Hey Coolidge,

     I think maybe stay with slot style, as may take too long to get  up to temp across diameter of circle???  Just a gut feeling on that one.  Also think maybe coals will always be falling through a circle of equivilent sq inches of the slot.  But, could be (probably) wrong on that and since a repair job will be "on order", nothing to lose by giving it a try!! 

     As always, keep us informed, when time comes.  Assume you won't be tackling that project until end of burning season?  A little experimenting will surely yield a fix.

     Sure glad the forum is back, as these small quirks we have, are far better solved by a group of users, as opposed to "your on your own".

     

[coolidge]

Bill,

     Thought of the coals falling in there, but i might give it a shot this weekend.I am thinking of starting with a 3/4 inch circle so i can go up from there. Then again its supposed too cool of quite a bit so i might just leave it alone and cut some wood if it freezes.

[tinner]

I really think that you should give it a try this weekend regardless of the weather...lol   I am trying to finish up my design for my home built Gasser.  so any info that you could share would be great!

Thanks!

[Bill G]

Coolidge,

      Stephanie says a brief cold spell on the way!  Sure enjoy watching the weather channel, but mostly go outside and make my own prediction!  But the scenary on the weather channel is a good morale boost!

      A series of 3/4"holes?  Not just one...would think you need to keep the same amount of square inches leading into the chamber.  Also, the slot is tapered smaller on the bottom side.  Marty said he aquired some very high temp refractory cement for when he does his.  Will have to ask him for more details on this, but sounds like the stuff required. 

      Keep in touch....

Bill

[dwneast77]

Hi everybody,

I'm pretty new to this sight but I'm really glad I found it.  I've been checking back regularly and reading up on several brands of OWBs.  I've heard a lot of good talk about Portage and Main and I am considering it a future option.  I esp. like the new Opt. 450 they are offering since I heat several greenhouses.  Anyway, I found this thread to be especially interesting since it addresses a long time problem that I have faced.  I have 2 OWBs.  The first is CB E-Classic 2300.  I find it to be very touchy.  But the overall design is very similar to P&M Opt. 250, except how the primary air is introduced.  E-2300 brings the air in through the back wall  and across to either side along the bottom of the firebox, esentially making a big U shape.  This is good as it puts the air blowing right over the coals.  However, too much build-up of ash with block flow.  In my case the air channels along the side have deteriorated and even separated some from the sidewall thus allowing creosote to fill the air channels.  It has dried and caked in there very tightly barely allowing air to pass with no way to really get in there to clean it out.  It has built up so bad that it too backs up into my air box.  Which leads me to a question.  The end of the tube in my CB that is in the air box has a removable 90 degree elbow pointing up with a flat cover on it.  When there is call for heat the cover is lifted by a solenoid for both primary and secondary air.  Is the Opt 250 set up the same way??  Mine has never actually leaked into the air box because of the elbow, but my tube has been about 70% blocked before.  In pictures and vidoes I've seen of the Opt 250, there is a drain hole in the bottom of your air channel to allow for some drainage of creosote.  Does yours have that hole??


I recently mimicked the Opt 250 air channel design, rather than fixing what I had.  It's in pretty bad shape and again, full of crud.  So I had a welder help me run a 2 1/2" pipe to the top of my firebox and elbow toward the front to about the middle ending in a "T" to blow the air to each side.  Also, where the air comes into  the firebox, we came into a "T" so that the bottom side of the tube could rest on the floor but also act as a drain for creosote.  While I don't think this has fixed all my issues with this stove, I know I am getting sufficient primary air, and, the complete assembly is easily removable for cleaning.

Now I'm not sure if it's all just my wood to blame or not, but I do have signifigant trouble with bridging, having tried about every trick I can think of.  The worst, of course, is during times of high demand.  I did pick up a used WD 10000 to try to run along with my CB.  I've been test running it over the last almost week.  I don't know if it burns as clean as my CB is supposed to but I find it less tricky to operate, even with wetter wood (some that I'm just using up).  I see that the fire in the combustion chamber is much less intense because it doesn't really have a "nozzle".  The fire travels down through 4 slots running crossways spread out front to back.  Puts out amazing heat.  The other night I left my thermostat in my greenhouse, 27' x 72' set at 60 degrees when the outside temp dropped to below 0.  2 air heat exchangers running at 140k btu each.  Barely keeping the temp at 60 (keep in mind the ground in the greenhouse is cold if not frozen right now) but the boiler maintained water temp between 170 and 180 and would run through cycles and even shut down for a time.  My CB 2300 would have been brought to it's knees with that kind of heat load.

I've attached a few photos.  I really enjoy this sight and look forward to anything I can learn from everybody's experiences.  I can only hope some of my thoughts and stories can help someone else as well.

Jeff

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[Bill G]

Welcome aboard, Jeff!!!

     I've read numerous posts on the forums I visit, concerning bridging in the CB2300.  None in the newer 2400.

     Now that WD10000 is a conventional non-gasifier type OWB, and is for a larger sq. footage structure(s) as compared to the 2300CB gasifier.  It would be right that it carry's that kind of load better??  I'm sure with a bit more wood to do it, but the end result is what your after.  Heat!

     Good engineering on the air inlet piping!  I can really see from your pic's how that stuff ate up the air channel!  Now, your way allows for cleaning and gives the goo a bottom outlet back into the firebox where it can be of use. 

     I do see some changes, out of necessity, that I will attempt after season shutdown.  I'll certainly post them up here when done. 

     Thanks for your ideas, and keep in touch. 

     

[dwneast77]

Correction Bill,

     The WD10000 is considered a smoke free gasifier (they call it a converter).  Now the fire in the lower combustion chamber is no where near as intense but it is much larger and drawn down throughout the full length of the converter tube, from the front of the boiler to the back which is about a 6' stretch.  The biggest difference is that the "nozzle", if you can call it that, is 4 slots equally spread accross the floor instead of 1 that you see in all other gassifiers.  They make for a large surface area of the floor to burn hot so there is less chance for bridging to take place.  I can understand by the designs of most models that the hot spot would be right in the middle where the "nozzle" is, which is what happens with my 2300.  Now, the WD does tend to have it's hottest fire near the front of the firebox (since the air is introduced at the front door, it comes in through the right side of the door frame), but since that door is high in the firebox it doesn't matter if the wood falls forward.  The important thing is that the fire keeps burning hot.  You are right, heat is the main thing. 

A quick note on the performance of the 2300 since changing the air channel.  It has only been 2 days running, but fire seems to be favoring the back end.  I'm not yet sure how much better it's running, but I'm confident it's not any worse.  Like I said, at least I KNOW it's getting sufficient primary air now and I may open up that primary air solenoid a little bit as well and see what more air does.