Modern Glenwood Oak 116 - clinkers and still over firing!

Hello again! Hoping for some more of your awesome advice. We are definitely getting further along with our coal burning journey! However, we do need to tend to it every 4-6 hours!!!! We have golf ball sized clinkers and a lot of them! We also have some blue dancing flames but a lot of yellow too. The burn pot ranges around 600 degrees! Is that too hot? Dangerously hot?

We did put on a new ash door that is much tighter. We were lucky to find a 116 here in Vermont for parts!!!

We just did the "incense test" and see no air leaks.
We find every 4-6 hours in addition to shaking down we must stick a poker in the burn pot and kind of push down the coals otherwise the ash builds up above the grates and chokes our beautiful warm coal bed out.

Everything you have so far told me is there must be an air leak below the coal fire bed? However our incense test shows no leak. Could it be too much draft from the chimney?

Really appreaciate any advice. With the wind chill it's -28 here today!

Thanks again in advance!

Are you adding coal to the top of the bricks/refractory/firepot ? Only 4-6 hrs burn time sounds like you are only putting a few shovels of coal in. The fact that you have a clinker issue & the stove is running on the upper temp limits would also point to a low fuel level.

4-6 hour tending times is short for a firepot the size of a 116. With a lined firepot, that holds about 50 pounds of nut coal when full and should be able to go longer, but only if you can get it to slow down.

You say 600 F at the "burnpot". Is that where your measuring the temp, or on the barrel above the firepot?

Is the firepot lined with fire bricks, or refractory material ?

Do you have a manometer to check draft strength ?

Are you using a manual pipe damper to help slow the exhaust down ?

What size coal ?
If your certain there's no air leaks below, or at the level of the firebed, you can try mixing in smaller sized coal with what you have. The added resistance to air flow through the firebed can help slow and extend the burn times.

What brand of coal ?

Some brands of anthracite coal will burn faster, hotter, and more likely to form clinkers than other brands. The Tractor Supply Kimmels of a couple of years ago was like that. Burned faster and with bright yellow flames. Plus, it had a lot of iron in it that gave the ash a reddish color. And a few times I had to dig out some iron "meteorites" that fused together and quickly grew too large for the grates to pass through.

Paul

Nut coal- it has a Santa on the bag lol
I have infrared thermometer and the burn pot is coming in at 730 at the moment the barrel above pot is 440.

The pot is lined. I think it's with cement?

I don't have a tool to measure draft...assume I can get at local hardware store as the sell stove supplies or is this an Amazon buy?

See how the edges choke out first? This is how it dies out edges first but then if I catch it in time and stir and open the ash door dampers I can rejuvenate it. Sometimes I have to add math light or start all over.

Great questions men. I'm curious too why a stove of this magnitude won't out-burn my smaller 111. Sounds like you guys hit the nail on the head...maybe. A small coal bed, and a large draft. But he/she did mention there was an MPD (?), and it was fully shut. Wonder if they know which way is open or closed. I'm sure there's no manometer. It would be nice to see a photo of the install, and also a location, giving an indication of OATs. Hope they chime in soon. Would be a shame to see it taken out of service, because of disappointments. I'm sure once the OP gets the stove and methods dialed in, they'll be totally satisfied. Lucky to have such a piece of functioning history.
(Once again, beat by a couple mins to the button pushing.)

Yes I have a manual stove pipe damper it is always closed

I assume this is closed position

What other pics would you like?? Location? I Ann on the side of a mountain in central Vermont about 1000' altitude. Stove location is in walk out finished basement. Chimney is brick and is almost 3 stories high and has a chimney cap.

Thanks again...oh and I am a "she" lol

Yes, that "should be" closed, if no-one has monkeyed with it. If you're doing a proper ash clearing, (I'm assuming it has prismatic grates), could it be by shutting the MPD all the way down it's starving it for air? Have you tried it opened a bit? It looks like you have plenty of Blaschack coal to be burning longer than 4-5 hrs.
Also, how much air are you allowing in the primaries? Maybe a pic of that setting?

I assume primaries are the dampers on ash door? Here u can see the flames and my slits on the ash door

I do have blue flames but they aren't small they are about 2-3" high but no yellow at the moment

With a three story chimney it's likely you have a stronger than average draft. Better that than not enough draft !!!!!!!

Yup, with the MPD handle crosswise to the stove pipe it should be closed. But, if the MPD plate is cracked and a piece fell off. I had to replace my cast iron pipe damper this year. It had a couple of cracks in it and I didn't want to let go in use.

How wide open are the primary air damper in the ash drawer door, and the secondary damper in the loading door ?

The outer edge of a firepot will shed heat and go darker, but if it's dying and not burning until you give it more air you may not be clearing ash as well as it should. Do you rotate the grate bars one triangular surface at least once a day ?

Did you also do the incense test under the stove - up under the base skirt to see if there's any leaks in the ash drawer floor ?

Looking at your pix.
Firepot has plenty of coal, so that's good.
Coal bed has a nice mix of sizes, that's good too, because there's not a lot of large pieces and spaces that would breath more and burn faster.

One possibility is your setup has a very strong draft. What we call, "suck the cat off the floor draft". To get control of it, some stove owners install a second MPD in the stove pipe to increase resistance to exhaust flow.

Some install a "baro" in the stove pipe and adjust the baro leak air into the chimney system to reduce the draft strength.

Most of us use a Dwyer Mark II model manometer. It's not expensive - about $35.00 - $40.00. It not only helps troubleshoot stove problems, it also helps you reset the dampers for the best running position for your stove/chimney setup after each refueling. I doubt your hardware store will have a mano, but there are a bunch of online places that sell them. Just do a search of "Dwyer Mark II".

Paul

Yes, primary dampers are in the ash drawer door and the opening looks about right for working with a full closed MPD. And the firebed looks PLENTY hot enough. Blue flames sound like about the right size too.

If the problem is a too-strong drafting chimney system, what you can do is experiment with opening the secondary damper in the loading door. That lets air in after the firebed, which reduces the draft pull through primary dampers and the firebed. That may help slow down the fire and extend the burn time.

Paul

Thank you! We do clear out the ash pan and I am cautious of keeping it clear of the pyramid of ash that Wilson told me about to keep grates from warping!

Could we be shaking too much? We have a lot of embers in the pan when we shake?

We do are emptying ash pan twice a day! So much clinkers!

We have the secondary on the loading door closed right...will try opening that a bit!

Thanks again