Ash Build up on Grate

Looking for some advice on my alaska channing stove. I seem to have my ash build up and starts to back up to the point where the new coal is sitting and burning on top of the ashes. Which is blocking my air flow and it just really just doesn't seem to get a real good hot burn as it should. I've tried pulling the grate out and cleaning under it, sanding the grate to make sure its totally smooth and new gasket at the back of the grate. Running around .04 for draft according to my dwyer 25. Out of ideas and looking for suggestions. Thanks

I am not familiar with your stove, but if I wanted to deliberately have that happen I would put some spacers under the edges of the pusher block or whatever feeds the coal to raise it higher. That would feed the coal over the ash instead of pushing it in front of the coal.

So see if that feed is pushing right at the level of the carpet it is feeding and not riding up.

Is the ash forming into stiff clumps, so that it wedges on the grate and the fresh coal piles up and maybe goes over the side? I had that happen with the same stoker (in a 140). It turned out that I was using a "red ash" (i.e., high iron content) coal that formed clinkers when the unit was run hard. I slowed it down to use up that batch and switched to a white ash coal.

Mike

Welcome to the Forum!

I think Mike is correct here. This sounds like a "Clinker" forms as the stove is working hard. Very basicly, Different coal "Fuses" at different temperatures. If the amount of coal you are feeding in, and the amount of air you are feeding in causes the coal to burn at a temperature above the fusing point of the coal you are using, it creates a "Clinker". The clinker can stick to the grate, causing the problem you are discribing. Sometimes the clinker will travel down the grate and you will observe a long ledge of ash coming off of the grate and NOT falling into the ashpan.

There are one or two things you can do to recover from this.

1) If you see this happening, you can take a poker and brake the clinker up on the grate. This will get the coal flowing again until the next clinker forms.

2) Cut down the combustion air. This will drop the temperature of the burning coal, hopefuly below the fusing point of the coal. You can do this by partly blocking off the combustion blower air inlet with tape, or something.

3) You can also slightly turn down the feed rate if cutting the combustion air doesn't quite do it.

4) Try coal that was mined from a different vein. If you use coal that fuses at a higher temperature than your feed and air settings will create, it will not form clinkers.

Clinkers are something we all run into once in a while when we burn coal. If you put "clinker" in the search bar above, you will see a lot of threads about it on this forum, and a lot of solutions.

-Don

Ive burned a couple different brands of coal with the same results. Its not a real hard clinker I wouldn't say as they easily break apart it you poke it. Maybe its just the stove itself and the way it burns? I know there is so much more heat for the first 10min when there is nothing built up on the grate as to once it starts to build up.

StokerDon wrote:
2) Cut down the combustion air. This will drop the temperature of the burning coal, hopefuly below the fusing point of the coal. You can do this by partly blocking off the combustion blower air inlet with tape, or something.

-Don

Just what Don said !!!!!!

I get the same thing if I push my LL Hyfire II too hard.

You must cut back on the combustion air.

Rick

You have red ash, don't you?

Turn down the air.

If you are fusing white ash, you really need to turn down the air.

BTW: It has nothing to do with the your stove brand or model.

Thanks everyone. I taped off some of the inlet air and it seems to have helped. Coal pushes down the grate farther and not building up. Did loose a bunch of heat as I think I restricted it to much and wasn't getting a real good burn. So im playing around with it a little more to try and get my happy medium.

Weird, I've never experienced this. At least if it does I'll know how to remedy it.

Ed.A wrote:Weird, I've never experienced this. At least if it does I'll know how to remedy it.

Ed,

You must be feeding yours some good coal!

If you still have the 70,000 BTU grate in yours, that may be the key here. It is possible the the extra air from the 85,000 BTU grate pushes the original design over the edge?

-Don

Is this one of the stokers that they recommend to have the unit NOT level ,but rather a bit higher in the back to aid gravity flow ?

windyhill4.2 wrote:Is this one of the stokers that they recommend to have the unit NOT level ,but rather a bit higher in the back to aid gravity flow ?

You happen to have anymore info on that thought? I'll have to post up a couple of pics of how mine looks as I don't think its truly clinkers as much as feed and flow issue.

StokerDon wrote:

Ed.A wrote:Weird, I've never experienced this. At least if it does I'll know how to remedy it.

Ed,

You must be feeding yours some good coal!

If you still have the 70,000 BTU grate in yours, that may be the key here. It is possible the the extra air from the 85,000 BTU grate pushes the original design over the edge?

-Don

Don, to tell you the truth I dunno. My 1st stove bought new ( '07 Channing III) has been brought up with CSM bagged ( Munson Mass.) and until 4yrs ago Blashak bagged. My 94 Stoker II has only been fed Blashak and I've never had this issue. Poor air flow? yes, but cleaning the grate and the combustion air chamber of fines was key in getting the flow correct.

I'm more in line with air flow blockage as being the culprit.

jbc, in the thread titled ;Ready to buy a Keystoker Koker Lite ,on page 4 is where I found the "forward" tilt recommendation ,dont know if this idea works for other brands or if maybe yours is tilted to the back even slightly causing your issues.

here is a couple pics not the best but hopefully a bit of a idea. First is just ash and fire as it normaly looks and second is when I first knock the ash of the end of the grate. Kinda hard to see but if you look at it you can see how there is ash already burnt out sitting under the fresh coal.