Burning coal in a Royal Crown outdoor furnace

Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Sat Apr 05, 2008 9:50 pm

I am 36 years old and burnt wood my whole life. My husband and I purchased a royal crown furnace in nov. 2007 and decided to burn coal in the summer to heat our water so I started fooling around with this a couple days ago and it really sucks....... I cant keep a fire going and spend more time in the back yard than any where. I will get it so hot the furnace boils over and it will be out in the morning. The coal wont burn down enough to go through the grates so now they are jammed up and I can not shake it down I am using nut coal that is what is reccomended for this furnace. Please help I am gonna have to quit my job to keep a fire going. Thanks Kim :mad:
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: LsFarm On: Sat Apr 05, 2008 11:00 pm

Hello, caddykm. Most wood boilers have huge fireboxes to hold the large volume of wood needed to burn for a few hours and heat the boiler. But coal needs a different shaped firebox.

Most wood boilers use a fan to force air through the firebox.. is all your air going up through the grates,, with none of the air going in through the loading door, over the fire?? For coal ALL the air must go through the grate, NONE must be allowed to get above the fire.

Coal needs a deep firebox,, you need to load at least an 8" deep load of coal into the firebox.. a thin layer of coal will not burn correctly.. even if the boiler only burns say 3" of coal in a 12 hour period,, you can't burn just a 3" layer of coal.. you need to fill the firebox deep as possible.. then the coal will burn better..

On my wood/coal boiler I built,, very similar to your OWB. I had to shorten the firebox so that I burnt a smaller but much deeper bed of coal.

Once you get a deep load of coal burning, you can reduce the air to the fire, and keep the boiler from boiling over...

But be aware,, your boiler was really designed to burn wood, not coal.

Hope this helps.. 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: Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Sat Apr 05, 2008 11:19 pm

yes all air comes up from the bottom it is forced in from a fan. It has a huge fire box I could hold a square dance in it. Could we fabricate something to make the fire box smaller? The company told me I only need 25 pounds of coal for a good fire. I think they are huffing to many fumes. I put 50 in it today trying to get a decent fire. What can I do about the grates getting jammed up I have not been able to shake it in 2 days. Any ideas on burn times and how many lbs of coal I need a day? And also Can I burn this anthracite coal through the summer to heat water for the house? I have a big problem with paying $ 4.50 a gal for propane. Thanks for your help :idea:
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Visit Lehigh Anthracite

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: LsFarm On: Sat Apr 05, 2008 11:33 pm

I don't know what the grates look like on your make OWB... Or what the mechanism is like that shakes the grates..

Most wood burns to a fine powder,, coal often has chunks and hard pieces left over after they are burnt up. So most coal grates are designed with the ability to grind up the chunks.. and the shaker mechanisms usually have lots of leverage for this grinding action..

The only way to clear jammed grates is to let the fire burn all the way down, and clean the grates by hand.

Can you take a photo of your grates, or provide a link to the manufacturer's photos of the grates??

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: Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Sun Apr 06, 2008 12:24 am

http://www.crownroyalstoves.com/outdoor_furnaces.html
Then scroll down it has several pics hope it helps. I could not copy and paste them. Thanks
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: Richard S. On: Sun Apr 06, 2008 1:03 am

By the looks of the grates its not going to work very well for coal. What is probably happening is the coal on the sides of the grates is not burning... no air. When you shake it they are probably lodging in the grates. If you turn it off you'll probably find numerous pieces stuck in the grates on the sides. However I would't give up on it completely. Try giving it short chopping movement when you shake it. Don't fully move the handle .

Also try some pea coal, the grate sizes look small enough to hold it.

What you really need to do is add sides extending up from where the grates end, don't have any suggestions on how to do that. Sorry.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: LsFarm On: Sun Apr 06, 2008 1:22 am

Well, looking at the grates,, and mostly the almost flat shape of the circular firbox.. burning coal in this firebox is going to be really tough..

If you go to some of the stove sites for coal stoves and boilers and look at the way the firebox is designed, I think you can see what I mean..

http://www.harmanstoves.com
http://www.hitzer.com
http://www.alternateheatingsystems.com

You will see that a firebox designed to burn coal has vertical, firebrick lined sides, and the whole bottom of the firebox is a shaker grate system.
Coal is very tempermental to burn, unlike wood. Coal must be burnt in a firebox that is designed to burn coal.. you can burn wood in virtually any hand feed coal stove, but not the reverse.

You could go out and buy a bunch of firebrick and try to make a box around the grates in your boiler, and try to burn a smaller, deeper bed of coal.. but I don't think it will work..

think of a milk crate, made of steel, line the crate with firebrick, and make the grate on the bottom movable to shake the ash down,, this would be a small but good coal firebox.

You didn't mention the type of coal you are trying to burn,, if it is Anthracite, hard coal.. I don't think you will have much success. Bituminous coal or soft coal burns a little bit easier, a bit more like wood, but it still needs the above described firebox to burn well and properly.

Greg L.
2005_0410Woodstove70008.JPG
(39.25 KiB) Viewed 200 times
View: New PagePopup • Select:BBCode
My firebox in 'Big Bertha'.. the firebox is 54" front to back..
[nepathumb]3956[/nepathumb]

bridgeflash.jpg
(31.63 KiB) Viewed 151 times
View: New PagePopup • Select:BBCode
a too shallow fire
[nepathumb]3957[/nepathumb]

firebox1.jpg
(266.74 KiB) Viewed 155 times
View: New PagePopup • Select:BBCode
My new back wall to shorten the firebox, and allowing a deeper load of coal
[nepathumb]3958[/nepathumb]
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Sun Apr 06, 2008 1:31 am

I am burning nut coal
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: Richard S. On: Sun Apr 06, 2008 2:12 am

caddykm wrote:I am burning nut coal


Nut coal is in reference to the size, anthracite or bituminous is two types of coal. Preferably you want to use anthracite, mostly because it buns very clean. However your stove design maybe more suited for bituminous. I know there are a lot of people in my area having issues with the neighbors that have those wood boilers mostly in semi-rural areas. If you're in the same situation they most likely will appreciate it even less if you start burning bituminous.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Sun Apr 06, 2008 11:55 am

It is anthracite coal. I have no close neighbors. We are very rural
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: Steve.N On: Sun Apr 06, 2008 12:19 pm

Another problem with this design is the lack of fire brick to maintain the fire temperature. Burning against the water chamber will cool the fire at low burn rates something that wood will tolerate but not good with coal.
Attachments
shaker-grate.jpg
(49.94 KiB) Viewed 716 times
View: New PagePopup • Select:BBCode
royal crown grate system
[nepathumb]3965[/nepathumb]
Steve.N
 
Stove/Furnace Make: Harman mkII
Stove/Furnace Model: Axeman Anderson 260 at store

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: LsFarm On: Sun Apr 06, 2008 12:31 pm

Hi caddykm,,, here is what I'd try, buy enough firebrick to make a 'fence' down each side of the grate... unfortunatly firebrick are only 4" or 4.5" wide, so the box created won't be very deep.. but it might work..

The problem is that the firebox is a large diameter cylinder lying on it's side. the parts on the left and right of the grate are nearly flat,, and the air coming up through the grate won't travel sideways to coal resting on the cylinder,, only vertical through the coal directly on the grate..

The good news is that firebrick are not expensive,, somewhere around a dollar each... Try to make a wall down each side of the grate, to keep the coal bed vertical.. I'm not sure if the firebrick will balance very well on the edge of the cylinder or not...

If the boiler were mine,, I'd get a steel plate,, probably 1/2" thick, that would cover the rear half or 2/3 of the grate, the sides of the plate resting on the cylinder, but covering the grates, blocking the air from coming out anywhere but from the uncovered grate sections.. you would have to make sure the covered grates aren't prevented from moving,, which would lock the shaker mechanism...

Then I'd make a false back wall, resting this on the forward end of the horizontal plate.. and then make a 'rack' that rests on the cylinder around the open grates, this rack would be to hold at least a stack of firebrick 2-high, or on end, so 9" high,, the rack would be braced against the steel waterjacket-cylinder to keep it from being pushed outward by the weight of the stack of coal.

The above would create a 9" deep, by maybe 20-24" long firebox, that with the shaker grate below would hold probablly 50# of coal when full, and this deep coal bed would burn as well as can be inside your boiler..

I'm a fabricator, so making the above parts/pieces from steel is not a problem, maybe you have these skills too or know of someone who has and could help..

That's about all I can think of to help..

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: Burning coal in a Royal Crown outdoor furnace

PostBy: caddykm On: Tue Apr 08, 2008 7:36 am

Thanks for all the help. My husband and I have discussed making something for the inside of the boiler. We just have to make sure it can be removed easily because I don't want to quit burning wood entirely. We just had 40 acres of woods logged and have lots of wood. We were looking for something a little cleaner to burn for the summer to keep our water heated for the summer. Thanks again for the help
caddykm
 
Stove/Furnace Make: royal crown
Stove/Furnace Model: rs 7200

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: Sting On: Tue Apr 08, 2008 8:30 am

caddykm wrote:Thanks for all the help. My husband and I have discussed making something for the inside of the boiler. We just have to make sure it can be removed easily because I don't want to quit burning wood entirely. We just had 40 acres of woods logged and have lots of wood. We were looking for something a little cleaner to burn for the summer to keep our water heated for the summer. Thanks again for the help


How about finding a 1000 gallon old propane tank or build a non pressurized energy storage tank - attach it to your heating system and insulate it - burn your wood boiler hard and clean one morning a week and heat that tank - then use that stored energy to heat your DHW for the rest of the week.

That will also make wood burning easier in the winter as you storing energy to be used all day from a 3 hour hard burn twice as day - no more smoky wood fire smoldering when there is no need.
Sting
 
Other Heating: BurnHAM=NG-gas

Re: Burning coal in a Royal Crown outdoor furnace

PostBy: micker30 On: Sun Jan 23, 2011 1:34 pm

Just curious how you made out with using the coal in your boiler. I have the same one I've been playing with coal for couple of years. Especially when it gets cold. Can't keep it burning without wood mixed. I was told to try stove coal which is large pieces of coal. I'm just wonding if you finally was able to burn coal alone.
micker30
 
Stove/Furnace Make: crown royal

Visit Lehigh Anthracite