Outdoor Wood Furnace Info

All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: big don on December 11, 2014, 10:36:06 AM

Title: Help---Burning bit coal
Post by: big don on December 11, 2014, 10:36:06 AM
I have a Heatmaster 3000e and I just got a ton of Bit coal bulk.  I am burning with the draft open 100% temp at 175 with a 5* Diff.  I load at 9am and 9pm with approx 25 lbs of the coal and 5-6 pieces of oak wood 2yrs seasoned putting the wood on each side to make kind of a trench over the center of the grates to place the coal in.  The last 2 days every time I go out to load I find a big big ball of the coal sealed together about the size of a basketball, and when I shake & take my poker to break it up it is bright red on the bottom but no flame showing on the top half of this ball.  The stove was down to 145 this morning when I went out.  Has anyone else had the same problem, and what am I doing wrong , and what suggestion does anyone have to correct this problem? This is my first time burning coal been burning just wood the last 2 yrs with no problems. Normally with the wood I have been getting 12 to 14 hour burns with a nice bed of coals ready for reload.  Thank you for any advise anyone may have.  DON
Title: Re: Help---Burning bit coal
Post by: CountryBoyJohn on December 11, 2014, 11:31:47 AM
Cut your differential down to 2 or 3.  Coal is tricky.  Much more difficult than burning wood.  I save my coal for when it's colder than a witch's you know what.  Many more cycles and a bigger heat draw help keep it lit.  There are a couple "burning coal" threads in the Heatmaster section that will definitely help. 
Title: Re: Help---Burning bit coal
Post by: artbaldoni on December 11, 2014, 06:17:25 PM
You need to find coal from a different area or mix with some anthracite, if available. Alot of the bit coal swells and then melts together. Coke button I think its called. I am burning a mix of  stove sized ant and nut sized bit. Works great. If I get too much bit in the mix I get the same thing, swelling and bridging. Check in on nepacrossroads.com (http://nepacrossroads.com) they are the coal gurus, really know their stuff.
Title: Re: Help---Burning bit coal
Post by: DaveWertz on December 12, 2014, 02:03:58 AM
Try spreading your coals out more evenly. I use nothing but anthracite nut coal as thats what we have in my area. I use about 7 1/2 gal bucket full. I spread it nice and even then throw wood blocks on top. It seems that the wood catches fire then keeps the coal lite on top getting a nice even burn. I will go out every 10hrs or maybe more and stir with old garden hoe. Before adding new I stir, shake ash and repeat. I seen 30hr burn on the last load with it being in the 20s and low 30s with very little wood and the amount of coal I stated above. Stove is set at 180 with a swing of 5. Maybe you should also set your diff to maybe 2 or 3 life John said.
Title: Re: Help---Burning bit coal
Post by: artbaldoni on December 12, 2014, 07:33:26 AM
Don, Where are you located? Is anthacite available to you?

Dave, Have you tried bigger stove size? I have found the mix works really well. I have used mixed stove and nut ant but prefer the mix with bit for relights. My diff is set at 2°.
Title: Re: Help---Burning bit coal
Post by: Sloppy_Snood on December 12, 2014, 08:20:22 AM
I have used mixed stove and nut ant but prefer the mix with bit for relights. My diff is set at 2°.

Can I assume that a small delta T is one of the main "strategies" for burning coal in an OWB furnace?  Any other "coal-burning tips" you can offer?
Title: Re: Help---Burning bit coal
Post by: artbaldoni on December 12, 2014, 10:43:58 AM
Two things I learned in this adventure. Low diff, I have had mine set at 1° when burning all ant. You have to keep enough fire to relight the coal. If you mix with bit or wood you  can likely open the diff somewhat.

The other thing I have learned is that coal likes company. Coal is not like wood. More wood usually equals more heat. With coal the amount of heat is mostly regulated by the amount of air provided. Don't be skimpy with your coal bed depth. If you can regulate the amount of draft air you can regulate your burn. My stove has a forced draft blower with a sliding door that regulates the air flow into the firebox. Too much air and you lose large amounts of heat up the stack. Too little air and your fire goes out. You must find the happy medium through scientific methods such as trial and error... :o.

Don't give up it can be done!

http://outdoorwoodfurnaceinfo.com/forum/index.php?topic=4882.msg39550#msg39550 (http://outdoorwoodfurnaceinfo.com/forum/index.php?topic=4882.msg39550#msg39550)
http://nepacrossroads.com/forum-74.html (http://nepacrossroads.com/forum-74.html) These guys know their stuff but hate OWB users... ;).

Search for coal threads on here there is lots of good info.
Title: Re: Help---Burning bit coal
Post by: big don on December 12, 2014, 12:33:15 PM
Art,  I am located in winchester Va.  The closest mine to get anthracite coal is 3 hrs away.  I was able to get a ton of bit the other day with my pick-up but it was probably not the best since when the lad loaded me he picked up a huge load of what looks like dust from the cement pile that had the coal stacked. When I load my stove I get approx 1/2 a bucket of these fines mixed with the larger size coal.  Maybe this is part of my problem???  Have tried cutting back the diff to 3 and will know tomorrow what the results are and report back.  Thank you.  DON
Title: Re: Help---Burning bit coal
Post by: userdk on December 12, 2014, 04:06:55 PM
YouTube has an ancient video about coal burning in locomotives years ago. It explains how coal burns and whyhttp://m.youtube.com/watch?v=NHo860Q66Gw. (http://m.youtube.com/watch?v=NHo860Q66Gw.)
Title: Re: Help---Burning bit coal
Post by: artbaldoni on December 12, 2014, 04:50:23 PM
YouTube has an ancient video about coal burning in locomotives years ago. It explains how coal burns and whyhttp://m.youtube.com/watch?v=NHo860Q66Gw. (http://m.youtube.com/watch?v=NHo860Q66Gw.)

Very interesting but imho not really pertinent to burning for heat in an OWB. The breakdown of the piece of coal is ok asuming bituminous. Anthracite will be more carbon, more ash and less volitiles. "Little and often" might work if you are constantly tending your boiler like a locomotive fireman.

Volitiles do not account for much heat in our situation. They will off gas quickly and with enough heat and some secondary air burn and produce some heat. Heat over the extended period comes from the carbo which, with controlled air, will not be burnt up too quickly thus giving long burn times and the ability to heat  water to a desired temp without overshooting and boiling the water. Remember we are not (in most cases) using pressurized steam boilers. Our units are only water heaters.

I just came home from a 13 hour day to find my stove running at set point. I just shook out the ash and let it go. Will check and fire before bed to get through the night.

This is what my fire looks like when it's burning properly. All volitiles burned off, just burning carbon (blue flame). Nice and steady putting off lots of 🔥 heat!
https://www.youtube.com/watch?v=DTfBwfCPg7c (https://www.youtube.com/watch?v=DTfBwfCPg7c)
Title: Re: Help---Burning bit coal
Post by: stratton on December 13, 2014, 12:50:03 AM
Don, I to mix anthracite in with my wood loads.1/3 coal 2/3 wood increases burn times significantly.If you have time go over to nepa,lots of info and some great dry humor thrown in as well. good luck. Luke
Title: Re: Help---Burning bit coal
Post by: stratton on December 13, 2014, 12:51:33 AM
Art, More video please!!!
Title: Re: Help---Burning bit coal
Post by: stratton on December 13, 2014, 12:52:28 AM
Art, good lookin vid.
Title: Re: Help---Burning bit coal
Post by: AirForcePOL on December 13, 2014, 05:10:59 AM
Thanks for posting this.  I am going to go get a ton of bit coal once I get some free time and I'm sure I'll have some questions.  I can get it from a mine a couple miles down the road for $70 a ton so I figured I would try it out. 
Title: Re: Help---Burning bit coal
Post by: big don on December 13, 2014, 09:58:30 AM
Well I had only half success with the diff @3 and about 6 pieces of wood and approx 20 lbs of Bit coal.  The large ball that I wrote about above was only about half the size of previous days.  at the 10 hr mark the temp was down to 156. Sure wish I could get my fire to look like the pictures that art showed with the success that he is having---I guess the secret is to have the Ant coal which is not available in my area. Thank you to all of you who have responded to help with my problem.  Merry Xmas.  DON
Title: Re: Help---Burning bit coal
Post by: artbaldoni on December 13, 2014, 11:00:52 AM
Don, I called Tractor Supply in Winchester
 They have bagged ant nut coal there. Give them a try.
Title: Re: Help---Burning bit coal
Post by: big don on December 13, 2014, 02:17:02 PM
Art, Thanks for the heads up on Tractor Supply and the Ant coal, however they just sold out this afternoon but the mgr said he would try to order a new order from the dealer but could not assure me that they would get anymore in---will call me back next week to let me know if they will be able to get it.  It's kimmel not nut size ant 50 lbs / bag $237 /ton--- a really good price I think.  Don
Title: Re: Help---Burning bit coal
Post by: DaveWertz on December 14, 2014, 09:17:39 PM
Don, Where are you located? Is anthacite available to you?

Dave, Have you tried bigger stove size? I have found the mix works really well. I have used mixed stove and nut ant but prefer the mix with bit for relights. My diff is set at 2°.
Yeah I have tried bigger lumps. I had trouble with recovery time with the bigger lumps though. I found that keeping my diff at 5 or less and load with coal I see best results. Its nice with how it works for me. I can go back out 6hrs later, stir the coal around and have a nice glowing bed. I then shake all that ash it produces add more coal and a few pcs of wood and shes good for at least 20hrs +/-. I have even burned straight coal and had good succes with that as well.