don't burn wet coal

I learned a lesson the hard way. My coal is really dry so I have been watering it down when filling the hopper to reduce the dust. Today I smelled sulfur so I went down to check it out and while there was 200 pounds of coal in the hopper I could see the auger in the bottom of the barrel. The coal stuck to the sides and made a huge funnel. So I just pushed it down, added another couple hundred pounds and went away. Fast forward and we're freezing a few hours later. The wet coal made a pocket around the auger in the bottom of the bin so it wouldn't feed and the fire went out. I had to shovel all the coal out of the hopper because I thought the auger had broken, come to find out it wasn't broke just packed with wet coal. I never had a problem using dry to slightly damp coal but too wet is definitely bad.

BTW I got to thinking about things like holiday breakdowns (because things only break at the worst possible time) if the auger ever breaks can it just be pulled out and welded and put back into service?

If the coal is really clean that shouldn't happen. You have two reasons why that will happen. The water when combined with the coal produces a liquid that is sticky when dry, something like a glue. The other problem is with the fines, as the coal keeps going down the dirt will gravitate to the sides and bottom and it will collect into the spaces between the coal. Over time you'll get a build up of it and it can develop a situation where you can have very steep angles. Think of sand if you dig into the side of it, you can have almost a vertical side when you pull the shovel out.

About welding the auger, I have never tried to weld an auger from a boiler but have welded post hole digger augers without a problem. I guess you can do it. Just have to keep it straight.

So much for the watering idea, huh? You can use a hand spray can full of light oil if you have to, but watch out for getting too much on the coal. I know first hand about the auger issues that will 'cake', and believe me, you were lucky too.

I can't say enough about having spares on hand. Motor, auger, shear pins, coupling for the blower, a spare circ or zone valve head, some control parts, wire, wire nuts...bolts.....I live out in the country, and there aren't any hardware stores close to me.and as excellent as Grainger and McMaster are, on Sat at midnight when it's 12 below and the wind is blowing 25 mph, that feeling of "I'm screwed", leaves you feeling ill.......................unless PPPPPPP! Or if you can't play 'think quick', then better go back to the porch with the little yappie dawgs, and let the big dawgs do their thing..

I think the worm shaft would be better welded with a TIG than with a stick. It's too easy to create a beautiful stick or MIG surface weld with no penetration at all. After all that, you have the issue of crystallizing the steel and having a weak spot. Better to have a spare bin worm on hand.

I've been having the same problems with wet coal this year. It's happened 3 times so far and it's getting annoying. I like to keep a full hopper, but I found that the more weight in the hopper the easier it is for the void to form. I stir the coal in the morning and at night before going to bed and when I add a bag, i keep it piled up at the rear of the hopper which gives it some time to dry out before its burned.

Last year the coal was wet too, but I never had this problem. The coal from last year was slightly larger and if memory serves, had less fines in it. This years batch of rice is smaller and appears to have more fines in it, but its burning a helluva lot hotter too - so im happy about that.

I have a neato idea to solve my void forming problem, I just need to find some time to get it going.

stoker-man wrote:I think the worm shaft would be better welded with a TIG than with a stick. It's too easy to create a beautiful stick or MIG surface weld with no penetration at all. After all that, you have the issue of crystallizing the steel and having a weak spot. Better to have a spare bin worm on hand.

I agree it would be better to TIG it. Also if you can have a spare that would be the best thing to do. I was thinking in case of Sunday, nothing being open to get parts. Welding can be a quick fix that should last till a new one can be installed.

Most stoves state right in the manual, do not burn wet coal.

Have stick welded many worms and never had a problem, just got to do it rite,chamfer,correct heat and correct ss rod.I wouild tig it but my tank is always MT.






ry

Are the augers cast iron?? From pics they looked like they may be. If so they're going to be quite a bit tricker to weld. Need to pre heat with torch and use a cast iron electrode (high nickel content). Then hit again with torch and let cool SLOWLY or you'll develop cracks in the weld. If mild steel weld away with mig, tig or stick

No, they're stainless. I think 410.

You guys are right about the excessive fines this year in the rice coal. Stoker Man or other EFM dealers, have you ever seen a worm break before the shear pin? assuming the correct shear pin is installed?

Have seen them wear thru at the flight from pot rub.





ry

As I posted earlier, not all mechanism operate well with wet coal, Stoker stoves using a slider/carpet movement don't seem to have any problem, pushers and augers are different story !

Just to add to what I posted above if you have a lot flat stuff (bone) that can exacerbate the problem too.

GeorgiePorgie wrote:augers are different story !

Never had this problem in almost 30 years.