SETTING UP AN OUTSIDE BOILER TO BURN COAL

SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: CARROLLMOTORS On: Wed Dec 17, 2008 3:35 pm

I HAVE MODIFIED MY OUTSIDE WOOD/COAL BOILER TO BURN COAL ONLY (IT ALSO BURNS WASTE OIL). I HAVE HAD SOME SUCCESS. I KNOW ABOUT THE EFFICIENTCY ISSUES WITH OWB'S BUT FOR OUR SITUATION THE UNIT WAS AREADY THERE AND IT'S INEFFICIENT WITH WOOD OR COAL AND COAL IS EASIER. I DO HAVE SOME GENERAL QUESTIONS ABOUT ARANTHICITE COAL BURNING. HOW OFTEN TO SHAKE? DAILY? EVERYTIME YOU LOAD COAL, TWICE A DAY ECT. POKING OR STIRRING UP COAL BED GOOD IDEA YES OR NO? I WOULD COMPARE OUR USE TO AN OLDER HAND FIRED FURNACE. COAL 8" TO 10" SO DEEP AND SURFACE AREA OF 16"X30". I WOULD BE HAPPY TO POST WHAT I DID TO THE BOILER BURNING STOVE COAL ACCEPTABLY IF THERE IS INTEREST. I BELIEVE THERE ARE ONLY A SMALL HANDFUL OF OWB BRANDS THAT CAN BE USED FOR HARD COAL. MINE IS A HEATMOR 200 WITH A WASTE OIL OPTION. IN MY OPINION THE HEATMOR DESIGN IS BEST FOR COAL BURNING BUT SOME MODIFICATIONS ARE STILL REQUIRED. AND YES I AGAIN UNDERSTAND OWB'S ARE BY NO MEANS THE BEST WAY TO BURN COAL BUT EVERYONE HAS A DIFFERENT SITUATION AND IT WORKS FINE FOR ME. ANY INSIGHT TO DAILY OPERATION TIPS ARE GREATLY APPRECIATED.
CARROLLMOTORS
 
Stove/Furnace Make: HEATMOR
Stove/Furnace Model: 200

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: titleist1 On: Wed Dec 17, 2008 4:09 pm

Welcome to the forum! We would love to see pictures of the boiler and the modifications! I have a hand fed and I shakedown twice a day when I load it. I poke around the front of mine every 2-3 days because the ash doesn't drop through the grates there as well and builds up over time. I don't know how well my procedure for an inside hand fed would translate to your outdoor boiler.
titleist1
 
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: efo141 On: Wed Dec 17, 2008 4:43 pm

I am new to coal but i dont think you should stir the coal like a wood fire. Dont shake a low coal fire get the coal hot first. I am sure some exp. coal burners will be helping you with info soon. some pix of the fire box and grates would probably help. Hows the waste oil burner working for you ?
efo141
 
Stove/Furnace Make: New Yorker/Keystoker
Stove/Furnace Model: WC90-----/Kaa-2

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Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: LsFarm On: Thu Dec 18, 2008 1:27 am

Hello CarrollMotors.. welcome to the forum.

Shake often enough to keep the ash from accumulating on the grate to clog the air passageways.. this is usually about every 12 hours. It depends on the burn rate. Generally people try to load coal, let it get burning, then shake down the ashes.

Poking a hot fire will create clinkers. Clinkers are stuck and melted together clumps of ash. When you poke a hot fire, the red-hot coal pieces are forced against each other, causing them to stick together..

Some fireboxes and grates need to have the ASH under the fire to be stired to get the ash through the grate.. for this job make an "L" shaped tool, the "L" end is run under the ash just above the grates. This is needed in some stoves to help break up the compacted ash and help the shaking action to clear the grates.

Unlike wood, coal burns from the bottom up, this is why anthracite coal needs to have all the combustion air come up through the grates.. With the coal burning from the bottom up, the ash is on the bottom, burning coal next layer, then unburnt coal on top.. Stirring the coal upsets these layers, which upsets the way anthracite needs to burn.. the ash needs to dropped out from the bottom through the grates. stirring mixes it with the burning coal, creating clinkers and if there is too much ash, the fire will go out.

Greg L

BTW: PLEASE don't type in all capitals.. this is considered yelling.. and is hard on the eyes. Thanks.

Greg
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: Freddy On: Thu Dec 18, 2008 8:04 am

If possible don't mess with coal from the top, come up from under it to clear ashes. Not that I'm experienced, but I've read how several people with hand feds will:

Use shaker only. Shake until you see orange start dripping into the ash pan. Now look from under. If it's a nice even orange, you're done. If there's dark places, poke from under with L shaped poker to clear those dark spots. Failing that, (Like once a week maybe the corners won't come clear), some will shut it down & start over. Others never shut it down all season. They will get it going hot, don't add new coal yet, then from the top dig out half & clean the built up ash, then the next day do the other half. After cleaning half I don't think they rake it level, I think they just add new coal & the fire will migrate over. Just not sure...maybe they rake a thin bed of "hot" over to the clean half & then add? There's a learning curve!
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: rockwood On: Thu Dec 18, 2008 10:03 am

CARROLLMOTORS wrote:AND YES I AGAIN UNDERSTAND OWB'S ARE BY NO MEANS THE BEST WAY TO BURN COAL BUT EVERYONE HAS A DIFFERENT SITUATION AND IT WORKS FINE FOR ME.


I think outdoor boilers are fine in the right circumstances. OWB's get a bad rap because they go into "smolder mode" when there's little call for heat which produces a lot of smoke and irritates close neighbors. Coal is the best for this type of situation (IMO) if the boiler is designed to burn it.
rockwood
 
Hot Air Coal Stoker Furnace: Stokermatic coal furnace
Hand Fed Coal Stove: Rockwood Stoveworks Circulator
Baseburners & Antiques: Malleable/Monarch Range
Coal Size/Type: Soft coal: Lump and stoker (slack coal)

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: CARROLLMOTORS On: Thu Dec 18, 2008 12:38 pm

Here are the modifications to the heatmor. I installed the shakers bought from Heatmor. Very nice grates not bad to install. I made racks for firebrick
to bring the brick to the edge of the grates. They are angled to accomodate future wood use as I have wood left to burn. I am going to stand bricks straight up around the perimeter of the grates with a different rack when wood pile is gone. To keep fire going while idling I added a repeat cycle timer to the draft supply fan. Fan is now running for 60 seconds every 10 minutes. The cycle timers are highly adjustable but this setting is working as the fire has not gone out yet. Heatmor unit is working quite well. adding coal twice a day. I went 16 hours last night with outside temps in upper 20's. Fire was in geat shape after this duration water temp was still 160. Right now I am adding 100#'s of stove coal a day. Temps here in upstate NY are upper 20's and low 30's. This OWB is working very well on coal. A lot of the bad wrap of OWB's is some brands with poor design and users burning green and garbage wood/fuel because they will do it. It cuts the effientcy burning green wood in a OWB no differntly than burning green in a wood stove. Rule of thumb is it costs 60% of BTU's of wood with green or wet wood to remove mosture/sap. 100'K btu's with 8% moisture content wood = 40k btu's with the same volume of green/wet wood. Enough about wood....this is a coal forum. I joined and posted to let some other OWB users that coal can be a very good option if your boiler is designed for it. As others in this very informative forum have stated, this previous wood user has no plans to ever go back.
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Grate rack
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Repeat cycle timer installed
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Waste oil option which works excellent!!
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CARROLLMOTORS
 
Stove/Furnace Make: HEATMOR
Stove/Furnace Model: 200

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: cArNaGe On: Thu Dec 18, 2008 2:13 pm

Can you show me how you use the shaker grates?
cArNaGe
 

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: CARROLLMOTORS On: Thu Dec 18, 2008 4:18 pm

Pictures added of shaker handle and shaker mechanism. This was all part of the conversion kit from heatmore. You do have to drill and put a collar pipe thought the outer enclosure and firebox for the shaker rod. It is welded to the arm plate as seen in the picture where the shaker rod is seen going into stove.
The handle pictured is supplied as well and slips over post when used and removed when not in use.
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shaker mechanism mounts in fan cavity
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shaker handle with fan cover in place
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shaker rod goes into stove though a sleeve
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CARROLLMOTORS
 
Stove/Furnace Make: HEATMOR
Stove/Furnace Model: 200

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: LsFarm On: Thu Dec 18, 2008 4:44 pm

Hi CM, one thing you may experience with your firebox design,, which is pretty much the same design I used to build my 'Big Bertha' SS boiler. the 'V' shaped firebricks act as a funnel or concentrator of the ashes.. this is fine when the ashes are dead and cool.. but if you get really hot coal ash being concentrated or funneled down to the narrower grate area, the hot ash and coal is forced together and this creates clinkers..

Your grates are rocker grates, and these are good at grinding up hard ash.. My grates in my 'BB' boiler are slider grates.. they don't tip or rock,, so they only shave the bottom of the ashes off,, this didn't do a great job.. So after a week of hot, hard burning in the dead of winter, I developed a sheet of clinker on top of the grate,, and it would block the airflow, and I'd have to let the fire go out and clean out the firebox, and start over again. This got 'old' real fast.

The 'V' shaped firebrick are one of the 'issues' with the OWB boilers, the US Stove units, and other combo wood/coal appliances.. the 'V' works great with wood ashes. but does not work well with coal.. But it can be worked around.. it's just more work every week. A made for coal firebox will have vertical or nearly vertical sides and the entire bottom made of rocker/grinding shaker grates.. this allows the fire to burn vertically down, without concentrating the ashes and creating clinkers..

With white ash coal, and not burnt too hot, clinkers are not often created, so you might do well with your OWB with the right coal and techniques..

Take care,, Thanks for sharing.

Greg L

.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: cArNaGe On: Thu Dec 18, 2008 6:00 pm

The V looks like it was the part that was fabricated. My heatmor has a flat bottom. No shaker grates. It has sand on each side of the stationary grates. I was curious how the shaker handle connected to the shaker grates, as I wanted to try to burn coal in my heatmor before buying something else. I called the factory and told me I couldn't retrofit my boiler, I needed to buy a new one. :P I bought the efm.
cArNaGe
 

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: CARROLLMOTORS On: Thu Dec 18, 2008 6:37 pm

I did fabricate the V section. The base I made under the V firebrick is 6 1/2 inches wide and goes over to the existing firebrick in the heatmor completely covering the sand. After reading the great information in this forum I am going to make another firebrick holder to keep the bricks 90 degree's vertical to the grates. I bought the kit from a dealer just outside montrose pa where it indicates you are from. Elk lake PA to be exact. Unless Heatmor has made design changes odd why they told you yours could not be done. My unit is 4+ years old. I was very impressed with the conversion kit. Old fixed grates come out and a plate for the rocker grates fits exactly in the angle iron rectangle the fixed grates came out of. Took maybe three hours to install. Could do it now in half that. I am just outside Binghamton NY if you wanted to see. But as you indcate you bought an EFM I'm sure not interested to convert now.

Thanks to all for all the great information this is truly one of the most informative forum's I've seen.
CARROLLMOTORS
 
Stove/Furnace Make: HEATMOR
Stove/Furnace Model: 200

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: rhfritz1 On: Sun Jan 11, 2009 10:37 pm

I also have a Heatmor 200 and this is the second year that I'll try to burn coal in it. I like your V firebrick design, I was thinking of doing something similar with mine because at the moment I just heap it up in the middle and it's not an efficient way to do it. I was also thinking about the firebricks at 90 degrees, but I wasn't sure if that would provide enough fire for the single digit temps out here near Buffalo, NY. It would however reduce the clinkers, which I have a terrible time with.
rhfritz1
 
Stove/Furnace Make: Heatmor outside boiler
Stove/Furnace Model: 200css

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: NOPEC On: Mon Jan 12, 2009 4:18 pm

in case you haven't figured it out yet, coal make a LOT more ash than wood. make sure you check your ash pan every time you load/shake. this was the unit i considered before getting my harman. how often do you have to load coal?
NOPEC
 
Stove/Furnace Make: Harmon SF-260 Boiler
Stove/Furnace Model: no-name Lowes woodburner

Re: SETTING UP AN OUTSIDE BOILER TO BURN COAL

PostBy: rhfritz1 On: Thu Jan 15, 2009 6:33 pm

I was actually surprised how much more ash coal produces, I went from auguring out the ashes every three weeks with wood to doing it every night with a coal fire. As shown in the pictures above, the shaker has a restrictor, so I do a restricted shake in the morning, then lift up the restrictor and do a full shake at night.

I load twice a day with about 100lbs a day. It's working so-so as long as I can keep the bed deep enough to keep it from burning through. This is certainly tougher than I thought, it requires much more maintenance than a wood fire does.
rhfritz1
 
Stove/Furnace Make: Heatmor outside boiler
Stove/Furnace Model: 200css

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