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Re: Coal Not Burning/Lots Of Soot

Posted: Thu. Feb. 15, 2018 5:50 pm
by Willis
Do you have this tied to a wall thermostat?

Re: Coal Not Burning/Lots Of Soot

Posted: Fri. Feb. 16, 2018 12:19 pm
by rockwood
Willis is on the right track here.
I have a stokermatic similar to this one.

If you have a smoky, sooty fire with lots of unburned coal then the fire is not getting enough air. A properly tuned stokermatic will produce very little smoke while firing. You shouldn't see hardly any smoke coming out of the chimney while the stoker is running.

As Willis recommended, I would open the under fire air all the way to start with. I would also set the above fire air setting to about halfway open.

If you turn the under fire air up all the way and still end up with lots of coke/unburned coal then you may need to check to see if the tuyeres are clogged with clinkers or rocks. The tuyeres are located near the top of the firepot. Use a flashlight and look for pebbles, etc., stuck in the slots. A small screwdriver works well for cleaning out the air slots. Also, you should check the wind box area below the firebox to make sure it's not filled with ash/clinkers/rocks. Remove the small plate with two bolts behind the ash bucket to access the wind box.

Is the coal wet? Wet coal will cause the fire to burn less efficiently because the water will have to be vaporized before the coal can burn properly. Also, wet coal will eventually cause the hopper to rust through.

I attached a video showing what the fire should look like. Keep in mind that coal I'm using doesn't make coke trees.

Re: Coal Not Burning/Lots Of Soot

Posted: Fri. Feb. 16, 2018 2:01 pm
by europachris
Weren't the Stokermatic units designed to burn Western coals (Utah/Wyoming)? Those have less BTU content and do not coke. With Eastern coal there may not be enough air even wide open to burn it fast enough. I'm thinking that considering the BTU ratio between the two coals (about 8,000 vs. 12,000 per lb.?) the pulley ratio might need to be adjusted. 12,000 BTU coal is 50% more heat per pound over 8,000 BTU coal. Doing the math to run 12,000 BTU coal at the same BTU input rate as the 8,000 BTU coal, you need to reduce the feed rate 33% by whatever pulley size changes required - i.e. going from a 3" drive pulley to a 2" drive pulley. The exact change isn't going to be very critical as long as it's somewhere in the range of 25% to 35%.

One other thing....make sure nothing is blocking the air flow thru the "plumbing" from the blower to the pot. I rebuilt/restored an Iron Fireman stoker a number of years ago and when I first tested it prior to tear-down I was underwhelmed by the amount of combustion air being supplied. I checked it all over and couldn't find anything until I disassembled the damper/adjustment portion of the duct. I had found a few acorns previously but nothing compared to the mother lode!
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Re: Coal Not Burning/Lots Of Soot

Posted: Fri. Feb. 16, 2018 3:58 pm
by rockwood
I don't have experience burning coals with a high coke button so I can't speak to that specifically, but the BTU of the coal I use is 11-12K BTUs.

I'm not at home right now so I can't check the size of the pulleys, but going off memory the pulley on the tranny should be about 5" in diameter and the motor pulley is about 2". The motor should be a 1750 RPM (1/8 HP I think) motor for this unit. All of the stokermatics I've ever looked at have these single grove pulley sizes. It would be a good idea to verify that the pulleys are the right size and not swapped (big one on the motor, small one on the tranny).

Checking the air passages between the fan and the airbox is a good suggestion too. These air passages can be inspected on these units by removing the motor (leave fan and fan shroud attached to the motor).

BTW, here's some BTU info quoted directly from an old Stokermatic manual that I have:
"The BTU rating of the Super Heater is based on coal having a rating of 12,500 BTU's per pound. Coals with lower ratings may be used but with corresponding reduction in heating capacity."

Re: Coal Not Burning/Lots Of Soot

Posted: Fri. Feb. 16, 2018 10:33 pm
by carlherrnstein
They made stokermatics that burn eastern bit coal they are like a left hand virsion of a Combustioneer, I think you are thinking of firetender with the rotating ash ring. I have a Combustioneer 77B (don't pay attention to my avatar) it took me a while to get used to it and there is a learning curve with these machines.

The black half burnt coal is coke dont pull it out, it's fuel, Coke is to coal as charcoal is to wood it will burn. Coke can form excessively if the coal has a high "coke button" this is not a bad thing and can be overcome. Coke also can form if there is too little/to much air or if the coal is fed into the fire faster than it burns. The first thing I would do is look in the "windbox" clean out it is probably covered by a small plate under the firebox door. Removing that plate will allow you to look for coal fines that have fallen through the tuyere assembly . You bought this thing used so it probably hasn't been cleaned out, it the area full of fines that will restrict airflow and cause coking.

If that is clear then you need to think about monkeying with the timer I would avoid this until you have to because it can be a pain in the balls.

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Feb. 19, 2018 11:34 am
by ghoulio
I just wanted to give a quick update. We couldn't get the heater to start with the air flow all the way open so we put it back to about 50%. We were going to turn it all the way up after it got going good but before we could do that the pipes caught on fire and we had to shut it off. Lots of smoke. Right now we plan on getting some pipe cleaners to see if we can clean them out good. Previously we had just been using a shop vac but obviously it wasn't doing the job. I'm unsure if we can even get it clean with pipe cleaners without taking the pipes completely off because there is only one way in, an elbow, and I'm thinking the elbow will prevent the pipe cleaners from reaching some areas. Does anyone have suggestions on how we can clean the pipes? It's supposed to be warm the rest of this week, not going below 50, so we're good for now. One of our local weather guys runs a blog and he says it's going to be cold again in March so we need to figure something out before then. I'll keep you all updated.

Edit: I just noticed this went to a second page. Reading the posts now and replying. Yes it is tied to a wall thermostat. We have it set at 70. Thanks for the video, it's very helpful to know how it should be burning. The western vs eastern coal thing makes sense. That could be our problem but the people we got it from used it for a long time so it worked for them I assume. I think the air passages are good because it was getting so much air we couldn't get the fire started. We checked the windbox beneath the firebox after we got it so it's good. I'll wait to hear if you guys have a suggestion on how to clean it out and in the meantime we'll try doing it on our own. Thanks so much for sticking with me on this.

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Feb. 19, 2018 2:10 pm
by rockwood
For the pipes to 'catch fire' they must be clogged with soot so before doing anything else you should clean the entire chimney. Start with the stovepipe that runs from the heater to the main chimney, take the stovepipe apart and take it outside and use some kind of brush to clean them out. An old car ice scraper/snow brush works well for this. I don't remember you mentioning what type the main chimney is but you really should get a chimney brush and brush it all out. Chimney brushes can be purchased at most hardware stores. If you tell us what type the main chimney is (masonry, metal...) then we could give you some advice on cleaning it. If you're not comfortable with cleaning the main chimney, you could hire a chimney sweep to do that.

The best way to start the fire in these heaters is by using newspaper and small kindling (a short piece of 2x4 split into small pieces works well). Let the paper/kindling get fully lit before turning on the stoker. If turning on the stoker blows the kindling out, just shut it down and add more kindling as needed. Make sure to have some fresh coal in the firepot (previously burned coal/coke is harder to light) and it works better to start the fire with an amount of coal that is no higher than the top edge of the firepot because if the coal is heaped up too much the kindling could fall off to the side and not light the coal.

These heaters, when tuned properly, will produce very little smoke.

One more thought...if the stovepipes are sooted up then the firebox probably has lots of soot too so you might need to brush it out.

Don't hesitate to ask more questions. We'll do our best to help you get it figured out ;)

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Feb. 19, 2018 2:40 pm
by BigBarney
This has to be running very inefficiently to get this much carbon in the

chimney. On my boiler I get a blue flame after some of the volatiles burn

off and it stays that way for many hours depending on heat demand. I

clean the chimney every 3 years and get about a 5 gallon bucket of fly

ash and carbon from its 34 feet.

If your getting that much your air flow must be too low , with the coke you

need higher temperatures to burn it completely.


BigBarney

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Feb. 19, 2018 5:02 pm
by ghoulio
It's a brick chimney. I would think it would be a major job taking the pipes apart and putting them back together. I will ask my father-in-law. My brother-in-law is not around anymore for reasons I'd rather not get into. My father-in-law is getting older and has memory problems so I'm not sure how much help he will be. It's mainly up to me and my wife to get this thing running now, along with all of you :)

Re: Coal Not Burning/Lots Of Soot

Posted: Tue. Feb. 27, 2018 11:15 am
by ghoulio
We started the stove up yesterday and with the new settings it's doing better. The fire pit is still full after 8 hours but a lot of it is ash. I'm beginning to think it's feeding to much coal but there is no way to adjust that is there? I'll try to get a video tonight of cleaning it out. It uses three five gallon buckets full of coal a day. I think our old stove used about that much.

Re: Coal Not Burning/Lots Of Soot

Posted: Tue. Feb. 27, 2018 10:03 pm
by BigBarney
Where do you live ?? Must be far north....

That's more coal than usual for this time of the year.

I get about 36 to 40 pounds per bucket.


BigBarney

Re: Coal Not Burning/Lots Of Soot

Posted: Wed. Feb. 28, 2018 4:12 pm
by ghoulio
Southeast Kentucky. Sorry I have not got a video up yet. The stove is doing much better considering where we were coming from. We are still taking ashes/clinkers out every 8 hours but it's burning more of the coal now that we have the air flow all the way up. Still wondering if it's feeding to much coal. I'll try to get the video tonight.

Re: Coal Not Burning/Lots Of Soot

Posted: Sat. Mar. 03, 2018 9:20 am
by ghoulio
Still taking ashes out every 8 hours. It's manageable but I think it's to many ashes/clinkers for that amount of time. Finally got some video to share. This is after 8 hours.

https://youtu.be/c22u4w0u6WA
https://youtu.be/TpqgDvC0pmA
https://youtu.be/UwSnl1XxMvA

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Mar. 05, 2018 3:51 pm
by rockwood
The huge buildup is coke (unburned coal). 3 buckets is a lot to run through one of these heaters per day, unless you're heating a big space during cold weather. A big buildup of coke is indicative of not enough air or too much coal feed. Since you've already maxed out the air, the only other thing to do is change the coal feed rate. Could you post a photo of the pulleys? You may need to put a smaller pulley on the motor.

Re: Coal Not Burning/Lots Of Soot

Posted: Mon. Mar. 05, 2018 7:36 pm
by McGiever
Here's a list:

May be worth checking if a faster RPM motor was used as a replacement sometime...


Stokermatic Superheater & Medicine Man 70 Parts List
Part Number Description

Stoker Drive Assembley

8480 "A" Gearcase,.New
8480 "A" Gearcase, Rebuilt *
8410 Feed Screw
8005 Inner Shaft, "A"
3243 Shear Pin 3/15 X 1¼
3275 Shear Pin,Retaining clip
3250 Coupling Pin, 1/3 X 1½
3145 0-Ring for Inner Shaft
3375 1/3 HP D/S Motor
3340 ¼ HP D/S Motor
3710 Motor Pulley, ½ X 2½
3760 Gearcase Pulley, 5/8 X 5½

1510 Belt,3L220
1520 Belt,4L250
9026 Stoker Fan Assembly, 8"
3720 Motor Pulley ½ X 3
3720 Moter Pulley ½ X 4
3740 Gearcase Pulley 5/8 X 4