Burn Efficiency

I have joined the coal burning society for the first time this year. I have an Alaskan Cast Console 3- a beautiful stove (pic attached). Even though it hasn't been the coldest, I have been burning coal so I get comfortable with things before the season actually occurs. From this I have come up with 2 questions:

1.) How can I tell how efficient my stove is burning? The cast console 3 is 85,000 btus with a 100lb hopper. I have noticed that for about every pail of coal I get about 1/2 pail of ash. I figure the more efficient the stove the less the amount of ash left over. Is this assumption correct and does anyone know what the ratio of coal in and ash out should be? I haven't weighed my ash but I plan to as well to compare weight in and weight out not necessarily just by volume.

2.) My second question is about the ash. I expected to be getting a true ash- powdery substance, however instead I am getting a mix of chunks of ash/coal (clinkers? ), non burnt coal, and powdery ash. I have watched to see if the coal is going up over the sides of the burner plate but it isn't. So, can the feed arm be set to high- pushing the coal over the burn plate to fast, therefore leaving coal not even touched and others not fully burnt and stuck together?

I greatly appreciate everyone's time and any replies

Hi Coalnewbie11, and welcome to the forum. I think alot of your questions maybe answered in a thread I started for my DVC-500. Here is the link....
Harman DVC-500 Efficiency

Coalnewbie11 wrote: 1.) How can I tell how efficient my stove is burning? The cast console 3 is 85,000 btus with a 100lb hopper. I have noticed that for about every pail of coal I get about 1/2 pail of ash. I figure the more efficient the stove the less the amount of ash left over. Is this assumption correct and does anyone know what the ratio of coal in and ash out should be? I haven't weighed my ash but I plan to as well to compare weight in and weight out not necessarily just by volume.

Generally the ash is by weight, a typical ash content might be between 8 and 14 percent. Half by volume is typical.

2.) My second question is about the ash. I expected to be getting a true ash- powdery substance, however instead I am getting a mix of chunks of ash/coal (clinkers? ), non burnt coal, and powdery ash.

That's typical as well especially with a stoker. There shouldn't be a lot of coal left but some is not uncommon.

Here's placard from a old Van Wert. Quite dated but still applies.

On your stove, not sure if the combustion blower varies with the feed rate on that one, or if the combustion blower running 100% all the time. If it varys, you can re-wire so it run 100% of the time, that helps keep it burn up better. Other than that, you are getting what most people with their stoves too. Coal quality will give you more or less ash, but you also will get unknown things in it too that do not burn.

You said 1 pail? How big/weight of the coal? to 1/2 pan? SO, approx. 50# of coal in, about 5-10# of ash approx out in about right.

Good luck. have fun and enjoy the heat!

Top vents tend not to run as effecient as a bottom vent stoves. You could try putting in a heat reclaimer that may help a little. If I was you I would install a manometer and a barometer to adjust the draft in your stove. Are u running a direct vent or power vent?

Welcome Coalnewbie11. great pics!!

Keep in mind, the high efficiency of burning coal already has factored in what you are seeing in the ash pan- all normal. I believe your combustion burner has 1 setting, so make sure the fan inside the door behind the grate is spining freely and fast and the one in the door is doing the same. You may want to shut it down momentarily to ensure that the blades aren't damaged, if not you should be getting full combustion. I would have to say with the ratio of fill to ash that you state that it would be nearly an impossibility to not be experiencing full combustion.