Smoke in Coal Bin

I'm getting smoke in the coal bin again. Draft seems good. The coal was frozen when dumped in the bin. Can the cold temperature of the coal bin draw in smoke? Maybe the auger is too worn down and allowing smoke down the feed tubes? I've run out of ideas on how to fix this problem so could use some suggestions.

Just checked the airflow through the pot is very low now, and the flames are only 3-4 inches high. Draft is good. Some air is coming out of the blower inlet too so something is clogging the air flow. Does wet coal prevent air from flowing through the coal in the pot causing it to go down the feed pipe?

Right in the middle of a welding project and its freezing out!

Thanks,

Dave

Assuming the chimney isn't plugged, it sounds like your grates are plugged with fines and the air can't get through. Dumping frozen coal in the bin is just a bad idea.

Are you taking your draft reading when the unit has been firing for a few minutes and during firing? You should be able to see the throttle plate in the fan when the motor is removed. Is it opening and closing? Is the motor coupling tight on both sides. Is your fan turning in the right direction? Looking in through the small opening at the coupler, it should be turning in a CCW direction.

feeding directly from the auger is a bad idea, Put a 55 gallon drum on the end of your auger, and a screen on top of it, then fill it with buckets, this saves alot of junk from blocking your pot

Frozen coal sucks

I'm bringing in 5 bags now, and letting it unfreeze and drain before I put it in my coal bin. I get a lot of water out of these bags. I tested the bags, and they don't seem to pass water so assume its bagged with a lot of water? The wet coal has been creating a lot of problems for me in the DF520. I have all the pallets of coal covered with plastic since I received them so they are being delivered with water in the bags.

If it's Blaschak bagged coal, they have a drying system. They claim that after it leaves there, it's gaining water at wherever or however it's stored.

That is Bull. Water runs out of the bags and they are sealed. I heard from a reliable source that they allow 1500lbs per truckload of bulk for excess water.

stoker-man wrote:If it's Blaschak bagged coal, they have a drying system. They claim that after it leaves there, it's gaining water at wherever or however it's stored.

I'll ask the place where I buy coal if they can get Blaschak next year.

I have no experience with Blaschak rice, but my coal from Kimmels was barely damp when I had it shipped immediately after bagging. After the pallets sat outside for a few rainstorms the first couple rows of bags were soaking wet.

I'm still having a lot of smoke in the bin, and detector is reading 40. I have rebuilt the pot, so next is to replace the augers. The pipe is hot 3-4 feet from the boiler so believe its hot air going down the pipe while running. The coal is burning good now. I'll replace the bin since I drilled holes in the bottom to let water out. I'm letting the bags drain in a separate bin now, so don't need the drain holes.

Any advise. If the replacement augers don't work then I'll have to remove the DF520 and replace it with a more efficient oil boiler.

Thanks,

Dave

If hot air is going down the pipe:

You have your air too high, your feed rate too low or a bad combination of both. Your draft is no good or the damper is set wrong. Your chimney is undersized or you have exhaust fans drawing air down the pipe. Your pipe length is too short or the unit is not sealed properly.

I'm thinking specifically a draft issue, not auger.

stoker-man wrote:I'm thinking specifically a draft issue, not auger.

I agree. Two days ago I had some coal gasses come out of my drum...found the flue pipe about 50% blocked with fly ash right behind the boiler. Cleaned everything, running perfect now.

I measured the draft and its -0.04 so should be okay. However, I'll put the draft inducer back in to increase the draft.

I have already brushed and cleaned the chimney and smoke stack.

I am running at 4/4. I have the longer pipe length with 4 inches of the auger sticking out into the coal.

The damper is adjusted.

Coal is not as wet as before. I opened a new pallet of coal, and the bags are much dryer.

So you don't think the auger has worn down so its not packing the coal tight enough to prevent air flow? I'll measure the diameter. Its the only thing I haven't fixed or rebuilt.

Thanks,

Dave

If you are sure that the smoke pipe and chimney are clear, -0.04" of draft should be ok. The big thing is that the overfire draft is -0.01" to -0.02".

Shut down and clean out the pot, see if the auger flights in the pot are sharp on the edges.

Also, are you sure that the holes in the pot auger pipe are clear and properly aligned with the pot?