Red Ash or White Ash

red ash or white ash

PostBy: brbrcron On: Sat Feb 24, 2007 1:45 pm

could somone tell me the differance between white ash coal and red ash.
Does one burn better than the other? Is there more ash with one than the other? anthracite I am asking about. Thanks!

PostBy: Jerry & Karen On: Sat Feb 24, 2007 8:46 pm

I think that the coal man could give the best answer.
Jerry & Karen

PostBy: Richard S. On: Sun Feb 25, 2007 12:08 am

Leisure Line wrote:I think that the coal man could give the best answer.

You would think wrong... :lol: I was actually hoping you had an answer for this question when I saw it posted in your section, have you ever ran both and compared?

Anyhow my expereience is with white ash, about the only thing I can comment on is that I have seen more than few cutomers with red ash from a previous dealer with quite large clinkers, as in softball size ones that had the weight and consistency of a rock. However I don't know if that is a common trait of all red ash coal and it may have been just that particular dealer or mine.

In other words I really have no idea. Interesting topic and looking forward to the reponses.
Richard S.
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

PostBy: Oo-v-oO On: Sun Feb 25, 2007 2:01 am

I'm relatively new at burning coal, but the stuff I'm burning now has a reddish ash and it's some of the worst clinkers I've seen. Not so bad as to seriously impact the function of the stove, but large and hard enough that they won't go through the grates.
The other batch I've been using this winter leaves more of a whitish ash and I rarely need to dig the clinkers out with that.
Stove/Furnace Make: Ashley

PostBy: Jerry & Karen On: Sun Feb 25, 2007 9:43 am

I can't comment on the clinkers, but I have asked the coal people (mines) about the difference. The answer is always the same. Iron content. They tell me the the red ash has a higher iron then the white. Also, on the threads about the BTU's, our stoves (feeders) have been tested to run about 6.7 lbs an hr without dropping hot coals off of the grate. In all of our brochures and lit. we claim to input at 90,000. Our claims are about 72,000 BTU output. I don't see anyone else making the output claim. We have run 8.4 lbs across out feeder without dropping hot coals off of the grate, but the quality of the coal varied. We use the standard of 13,500 BTU's per lbs, input, at about 80-83% eff. at burn. I'm sure everyone realizes there are great differences in the coal. Next time you put gas into a container, look at it and tell me if it's low grade, medium grade or high test. I think its the same with coal. It all looks the same (within reason) but burns different. I think anyone with a coal stove has saved money on heating, and I believe you should get the most for your money.
Jerry & Karen

PostBy: sparky On: Sun Feb 25, 2007 11:27 am

I never knew that there was such a thing as red ash / white ash until 2 years ago, I called my coal dealer for a load. He said he had a "deal" for me. He had a pile of uncleaned white ash coal that he had to move and was willing to sell to me for a discount. I asked him what kind have I been normally getting and he said red ash. He acted like the white ash coal is harder to come by and that it was top knotch stuff. I accepted.

You're right in that I cant tell the difference by looks.

I was leary at first but he was true to his word. I've gone through about 10 tons so far and can't remember one clinker yet. The ashes are Definitely white and seem to burn to a powder after being shaked through the grates.

Don't know about the heat output other than it seems the same.
Stove/Furnace Make: Harman
Stove/Furnace Model: SF2500 Handfired furnace

PostBy: Yanche On: Sun Feb 25, 2007 12:25 pm

I can some additional info to the white vs. red ash. Last week I bought a pickup load of Anthracite pea coal from a dealer new to me. He had most sizes in both white and red ash coal. I never knew there was a difference. He said his coal comes from two sources, Reading Anthracite and Pine Creek Coal Co. Reading coal produces white ash, Pine Creek produces red ash. He asked me what kind I was burning. I really didn't know. He got me some fresh ash from his burning stove. It was definitely whiter than my boiler's ash. I wouldn't call my ash red, but more a dull pink color, the clinkers have more of a color to them. Parts of the clinker have a reddish rust color. So perhaps there is some iron elements in the coal. The dealer would not make a recommendation of red vs. white ash coal. He said most customers try both and form a personal preference. I bough more of the red ash because it works well for me.

Enclosed are photos of red ash dust and clinker produced by my AHS S-130 stoker boiler. Notice the rust color in the center of the clinker.

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Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

PostBy: LsFarm On: Sun Feb 25, 2007 12:55 pm

Hi Yanche, with the sophisticated burner in your AHS boiler, where do you get a clinker to form?? Doesn't your grate move in a slow 'slicing' motion sort of like a continous gently shaking motion??

I didn't think your boiler would be able to create clinkers.

I wish you would try a few hundred pounds of the 'white ash' coal. You have a good attention to detail and could give us some valuable comparrison information.

I've burnt a lot of Reading anthracite coal, and I would not call it white ash, it is definitely a pink/red ash. And under certain circumstances I still got some impressive clinkers in my poorly designed hand-load firebox. Not as bad as I got with bituminous coal, but still clinkers clogging the grate.

Greg L
Last edited by LsFarm on Sun Feb 25, 2007 8:41 pm, edited 1 time in total.
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

PostBy: Yanche On: Sun Feb 25, 2007 3:14 pm

Clinkers form when the boiler has little demand for heat, like the warming spell a couple of days ago. Daytime temps were in the low 50's. During this time the grate stays stationary because it can only move when the combustion blower is on. Even then it only moves a percentage of the time the combustion blower is on, controlled by a 10 minute cycle timer. Note the size of the clinker compared to the postage stamp. It's small compared to those produced by hand fired coal appliances. It a very fragile clinker, easily crunched in your hand. The grate is a solid heavy steel plate that rests on four rollers. The clearance between the grate and the bottom of the firebox is about 1-1/2 to 2 inches. So that limits the size of any clinker. I've never had any larger. If they were larger when formed the moving grate would sheer it off. The gear drive grate motor and cam are strong enough to crunch unburned coal so a clinker will never stop operation. The weight of the unburned coal forces any ash and/or clinker to the grate.

Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

PostBy: CoalBin On: Sun Feb 25, 2007 9:42 pm

THis may help from Harman
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Stove/Furnace Make: Harman
Stove/Furnace Model: DVC-500

PostBy: coalstoves On: Mon Feb 26, 2007 6:24 am

My own experience with the two types is that the Red Ash requires more air to burn which isn't much of an issue in a stoker but some Franco Belge and the American knock off the Victory 700 that have marginal draft situations can have problems burning it . I prefer the white ash .

This scan is from a book written and published between 1848 and 1855 one of the few comparisons I could find .

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Stove/Furnace Make: Harman and Liberty
Stove/Furnace Model: Magnum and Victory 700

PostBy: Charlie Z On: Mon Feb 26, 2007 8:18 am

Was that $5.50 a bag or per ton? :lol:
Charlie Z
Stove/Furnace Make: Coalbrookdale
Stove/Furnace Model: Darby

PostBy: Yanche On: Sat Apr 07, 2007 9:55 pm

I've finally tracked down some info about red ash coal, at least where the term may have come from. The U.S. Geological Survey has named all the coal fields in the US. There are hundreds, perhaps thousands of names. The Pennsylvania BUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEY lists coal veins in Luzerne and Lackawanna counties as Red Ash, Lower Red Ash, Middle Red Ash, or Upper Red Ash. See complete description in the Appendix of "COAL IN PENNSYLVANIA", available at: ... al/es7.pdf
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Coal names

PostBy: Charlie Z On: Sun Apr 08, 2007 9:21 am


When you read about the Navy during its time using coal you come across references to the type (name) of coal they used. Captains needed to know the differences between coal to judge the range of the ship. They also wanted 'smokeless' coal to be less detectable.

Here's a link on spontaneous combustion and Navy coal, as related to the USS Maine:
Charlie Z
Stove/Furnace Make: Coalbrookdale
Stove/Furnace Model: Darby

PostBy: Hardcoaler On: Wed May 02, 2007 9:23 pm

I have mined cleaned and burned red and white ash coal for over 30 years. The quick answer in reference to the difference between red and white ash coal is the tendency for the ash in the red ash coal to melt and fuse, thus forming a clinker. This is actually a very complicated phenomenom. The main culprets are iron and silica in the ash. The coal must have the proper ratio of iron and silica in order to form a clinker. However red ash coal tends to have a higher calorific value, which will give more heat per ton and normally has a higher percentage of volitale matter which will tend to make it burn longer, stay lit longer and light easier. Most prep plants blend white and red ash coals in order to create the most favorable end product. If you would be burning pure red ash with an ash fusion temperature of 2600 degrees the ash would be fluid on your grate and adhere to the grate. The ash from red ash coal will tend to melt and adhere to whatever is in close proximity to it in the boiler. The desired blend has enough red ash to enhance the combustion of the white ash coal, but not enough to form large clinkers. If you are experiencing ash fusion difficulties (clinkers), the best remedy is to slow the feed of your stoker slightly and reduce the airflow slightly. Do this in small increments because as soon as you reduce the temperature of the fire in the bed below 2600 degrees all clinkers will cease to form. However the cooler the temperature of the fire the less heat is available for home heat.