KA6 Coking up in the Grates

BennyLumpkin · Post by **BennyLumpkin** » Wed. Feb. 05, 2014 8:41 am

Look at my pics and it's down when it was half open.

Post by **Rob R.** » Wed. Feb. 05, 2014 8:42 am

From page 3 of the manual:

Initial coal feed: Advance red nut all the way forward. Then turn it counter clockwise 11 or 12 turns if burning rice coal, if burning buckwheat coal turn coal feed, back 9 or 10 turns. When boiler is running for about an hour under full load grates should have about 2” of dead ash on them before falling into the ash pan.

From page 4:

Location and final placement for red nut will be determined by size of coal you purchase. For rice coal, red nut might be turned down 12 turns for maximum setting, whereas for buckwheat coal, red nut might only be turned down 10 turns from maximum setting.

BennyLumpkin · Post by **BennyLumpkin** » Wed. Feb. 05, 2014 8:44 am

I think I'm around 11 turns for rice right now.

blrman07 · Post by **blrman07** » Wed. Feb. 05, 2014 8:50 am

What's the color of your ash? Depending on the iron content you can adjust that combustion air all you want and your still going to clinker up. Sounds like the coal. You may have had it in your bin since last year but that doesn't matter. If you unit has been running flat out it's running hotter which will form clinkers. A lot of people have developed show stopping clinkers this winter due to having to run their units flat out.

Rev. Larry
New Beginning Church
Ashland Pa.

BennyLumpkin · Post by **BennyLumpkin** » Wed. Feb. 05, 2014 8:54 am

White

McGiever · Post by **McGiever** » Wed. Feb. 05, 2014 8:56 am

BennyLumpkin wrote:Look at my pics and it's down when it was half open.

Okay, you got it. Hope you get it solved.

blrman07 · Post by **blrman07** » Wed. Feb. 05, 2014 9:00 am

BennyLumpkin wrote:Yes I know the difference. .... right now it's completely shut. .... draft is correct and no change. When this all started I had it around half open and it always worked fine.

If you had the flap completely shut on the combustion fan you couldn't have a fire much less a correct draft and no change to the fire.

BennyLumpkin · Post by **BennyLumpkin** » Wed. Feb. 05, 2014 9:05 am

It's been shut for a week and burns perfect. A few guys suggested it so I tried it. Didn't notice much difference.

McGiever · Post by **McGiever** » Wed. Feb. 05, 2014 9:09 am

blrman07 wrote:
BennyLumpkin wrote:Yes I know the difference. .... right now it's completely shut. .... draft is correct and no change. When this all started I had it around half open and it always worked fine.
If you had the flap completely shut on the combustion fan you couldn't have a fire much less a correct draft and no change to the fire.

Thanks Larry, good to see I wasn't alone on this observation.

Carbon12 · Post by **Carbon12** » Wed. Feb. 05, 2014 9:13 am

Actually, even with the flap closed, it still blows air to the fire, just less air.

McGiever · Post by **McGiever** » Wed. Feb. 05, 2014 9:42 am

Carbon12 wrote:Actually, even with the flap closed, it still blows air to the fire, just less air.

No doubt.

BennyLumpkin · Post by **BennyLumpkin** » Wed. Feb. 05, 2014 7:41 pm

Double checked things when I got home. 8 turns but I have it fast hoping to push the coal off before it cokes up. My air feed it's about half. Draft is right. ... forgot I put it back to that setting. It was up in the mid 30's today and when I got home it was a solid cake on the grates. I just went down and checked it again and pushed a cake off that covered the whole burn bed. It came off the grate in one big piece.

gaw · Post by **gaw** » Thu. Feb. 06, 2014 3:21 pm

BennyLumpkin wrote:So I'm at a loss. We've had days in the mid 30's now and it's still doing it. Closed the air feed, adjusted draft again. Slowed the air into the combustion fan. ... even went do far as to wire wheel the grates and sides of the stoker too make sure nothing was built up for it to not slide easily. Even at super cold temps it gets hot enough to go off on its high temp setting so I don't think I'm asking too much of it. ... it did it with the buckwheat coal also but it was pretty cold out. I'm not sure what to try other than different coal again. ... ideas?

You did everything I would have done. I am stumped also. The only thing left would be the coal unless we are overlooking something. If you can get hold of some coal from a completely different source than what you are burning now it may be worth giving a try.

blrman07 · Post by **blrman07** » Thu. Feb. 06, 2014 3:31 pm

BennyLumpkin wrote:So I'm at a loss. We've had days in the mid 30's now and it's still doing it. Closed the air feed, adjusted draft again. Slowed the air into the combustion fan. ... even went do far as to wire wheel the grates and sides of the stoker too make sure nothing was built up for it to not slide easily. Even at super cold temps it gets hot enough to go off on its high temp setting so I don't think I'm asking too much of it. ... it did it with the buckwheat coal also but it was pretty cold out. I'm not sure what to try other than different coal again. ... ideas?

Could you please take a photo of the air feed that you said was completely closed and then a picture of the mechanism you used to slow the combustion air. I am still trying to wrap my head around completely closing the air to the burner and nothing changed.

Looking forward to the pics. They will go a long way....

Rev. Larry
New Beginning Church
Ashland Pa.

blrman07 · Post by **blrman07** » Thu. Feb. 06, 2014 3:37 pm

gaw wrote:
BennyLumpkin wrote:So I'm at a loss. We've had days in the mid 30's now and it's still doing it. Closed the air feed, adjusted draft again. Slowed the air into the combustion fan. ... even went do far as to wire wheel the grates and sides of the stoker too make sure nothing was built up for it to not slide easily. Even at super cold temps it gets hot enough to go off on its high temp setting so I don't think I'm asking too much of it. ... it did it with the buckwheat coal also but it was pretty cold out. I'm not sure what to try other than different coal again. ... ideas?
You did everything I would have done. I am stumped also. The only thing left would be the coal unless we are overlooking something. If you can get hold of some coal from a completely different source than what you are burning now it may be worth giving a try.

I just caught the bolded underlined phrase in the quote above. It is getting hot enough to trip on high limit even on the coldest days?

What by chance is your aquastat set at?