Plans for Wood/Coal Furnace Build

greygoose · Post by **greygoose** » Fri. Jan. 31, 2014 7:10 pm

I'm new to burning coal anthracite in particular, this is my first year with it and I'm in love haha. I just got a firechief 700 combo burner, that I absolutely hate, it works fine for just wood but the coal just clogs it all up and nothing will burn until I clean it out.
so I want to build my own with a whole different design (I own a machine shop with all the equipment necessary) and just want so input on some ideas I have.

I want two burn chambers, top one for coal and bottom for wood. so the wood will light the anthracite easily and I wont end up with wood ash mixing with the coal. I'd put shaker grates on both chambers and an ash clean out below as well as make the whole front swing open (like a refrigerator) for an easy full cleanout and maintenance. The whole thing will be 6-7 gage sheet metal with the chambers lined in stainless covered by fire bricks, neocerm glass doors, secondary combustion tubes and back draft damper. And maybe a stoker system down the line

Questions I've been asking myself while thinking this beast up are:
-Will the neocerm glass hold up to the temps?
-will anthracite burn better in a narrow/deep chamber or a wide/shallower chamber
-Is 6-7 gage thick enough to take the heat (.1943", .1793")
-Can I buy the high heat sealing rope long enough to reach around the whole front?
-Is the stainless even necessary?

What do you think? I'm still drawing it up on autocad and I'm open to ideas, so nothing is set in stone with it yet. I'm thinking the overall dimensions before I box it all in and hook it to my duct work will be around 7' tall 3.5' wide and 4' deep

Dennis · Post by **Dennis** » Fri. Jan. 31, 2014 7:36 pm

welcome graygoose,theres no need to redesign the wheel.You own a USS product and burns wood and bit coal good,but has real problems burning ant. coal. Your firecheif is the same as a clayton,hotblast and a few more I can't remember.your furnace needs some modifications,heres something to read and get you started on your way to burning ant. coal.
Successfully Burning Anthracite Coal in a Clayton Furnace

Dennis · Post by **Dennis** » Fri. Jan. 31, 2014 7:41 pm

Member "lightning" has a clayton and has modified his furnace alot and is having excelent success with his.I'm sure he will give you advice on helping also

Post by **dcrane** » Fri. Jan. 31, 2014 10:05 pm

ceramic glass is fine (you don't need a large window! go for the 1/4" if you can), coal beds like to be deeper rather than broad (typical preferred depth would be at least 8" deep coal bed for me), grates want to allow air up through the entire surface area under the coal bed, stainless is not necessary and it will hurt if anything (heat transfer sucks and it has zero tolerance to expand/contract), im not sure how your going to integrate the ash pan area for the coal ash while having this wood bed under the coal bed and two grate systems???? (I will wait for the plans...maybe im just not understanding the description correctly?) 6 gauge should be overkill... its the firebrick, the baffles you chose, the top plate that takes most the beating. door gasket can be bought in 100' rolls or longer if needed. im assuming for anthracite? the wood grate does not need to shake or move if your doing it separate from the coal bed/grate (it would be a waste of time and money), the coal grate is another story... thats going to be your toughest challenge im sure (i like the hanging basket/sliders) but whatever grate style you chose its going to require patterns and foundry (i just don't see a way around it unless you use an existing grate system from another product and simply incorporate it into your furnace?)... OK... just a few thoughts off the top my head, other will give theirs as well...

I also suggest reading some of lightnings posts "adding secondary air tubes" among some others.

Post by **Lightning** » Mon. Feb. 03, 2014 2:29 pm

Dennis wrote:Member "lightning" has a clayton and has modified his furnace alot and is having excelent success with his.I'm sure he will give you advice on helping also

Sorry I missed this earlier. I might be able to help you with that fire chief if yer interested..

greygoose · Post by **greygoose** » Tue. Feb. 04, 2014 10:09 pm

Sorry guys I've been swamped with work since I last posted. as far as the firechief goes I've been able to burn anthracite just fine, its their "innovative" 360 spin grate that is my biggest bitch with it, it just wont turn once theirs any weight on it (It'll shake a little), but not as much as it needs to restart a coal fire in the morning. Once it passes a certain point and something gets lodged in between it's a total clean out to get it to move at all, so I never move it more than a couple degrees in each direction(around 45 degrees each way). I've done a few modifications so far and once spring rolls around I'm going to take it into the shop and really get crazy on it, I'll post up some pics of what I've done so far.
I'm just the kind of guy that can't leave well enough alone and I think I can make a badass coal burner that eliminates any kind of issues that others have, I've done a lot of reading on other types of burners and have just been trying to come up with "the perfect coal stove"

The duel fire chamber, the main purpose of the wood chamber would be to light the coal and go out, any ash that falls into it at that point is not of my concern as long as the anthracite is lit. I would still want the wood chamber with a shaker so any coal that does fall though can be either scooped back up or just knock it down into the ash bin. I have two other coal burners I've never used (bought at an auction cause they went cheap) and I think I can just retro fit the grates out of the one massive one for both chambers, if not I work very closely with Akron foundry and could have them pour me one out, but I'd have to make the plates for the mold.

Thanks for the input everyone

I was thinking the same about the expansion/heat transfers of stainless. I just thought it would help the longevity of the burner in the long run to reduce corrosion, but I'm still thinking about using some as baffles maybe. That's awesome the door gaskets come in those lengths, as I've only ever seen them in specific door/burner sizes but I haven't really looked into that yet. I'll post some of my rough drawings that I have in mind, haven't had time to do any cad drawings yet, either way I'll keep the thread going as I go along with the project here in the spring and summer, I might even make a few scaled down versions if I have the time.