Shaking to Early?

Had my first coal burn a couple days ago. The fire burned perfectly over night. The coal had the blue flames dancing all over. Well I'll get to the point. It was about 0430 hours and I was getting ready to go hunting. The fire still looked great. I had put my final layer of coal on the night before around 2200 hours. I figured I would top of the fire before leaving so the wife didn't have to. I only shook the fire just slightly and something got stuck in the grates. I couldn't put the handle of the shaker back to the "Neutral" position as I would call it. I then moved the shaker a little more and this only made it worse. I never lost my fire though. I went hunting that morning and on my return I went ahead and lost my fire by shaking down the fire. What I think happened is I got a piece of slag caught between the grates. I called my coal supplier and he said that he felt I didn't burn hot enough and that what was stuck was actually unburned coal. I am burning Nut hard coal. Just when am I supposed to shake down the fire? What do I look for. Like I said I had a beautiful fire all night. Any help would be appreciated. I am new at coal burning and since my first coal fire the other night I have been burning coal. I am using a Harman Mark III

Did you examine what jammed the grate when you emptied the stove?

Shaking your stove takes some practise to get good at it. With the Harman shaker system, you can easily pull or push the shaker grates to far which will allow large chunks to possibly get jammed in the shaker grates. (Harman allows alot of travel in the shaker grates to make dumping & cleaning out much easier) Unfortunately, this labor saving shaker mechanism can also get you into trouble if you are just trying to shake down a good fire. Only practise with it will do the trick. You will find that short, choppy movements will work better than longer ones & taking your time is always a good idea. Whenever I try to rush things is when I have "jamming" problems. Good luck!

If you have a chance, look at the grates when the fire box is empty, look at how far you can move the handle before you open a gap between the grates' edges. Mark the handle postion with chalk on the side of the stove. Later when you learn the amount of shaker handle movement, you can remove the chalk mark.

This will help you from getting coal or rock jammed in the grates by opening/shaking them too far.

Greg L

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