Got my new stove!!!

How much heat in how big a room, insulated room or all glass, 7'6" ceilings or 11' ceilings.??. comparing apples to onions..
the bottom line is what is the stack temperature?? I believe that the stack temp on the DS will equal the stack temp in a chubby when the DS is burning twice or three times the coal.. The chubby is a small heater, the DS is a monster.. comparing grapes and watermellons..

Greg L

lobsterman wrote:

LsFarm wrote:ut 40# per day burnt in a small stove will not transfer as much heat into a room as 40# of coal burnt in a stove with a larger heated skin surface area.. unless the stove is terribly inefficient, and a hopper fed stove, like the DS is not ineffiecient.. or we'd have lots of comments, threads on the 'excess coal used' etc.. and we don't have that for the DS units..

GL

Efficiency = heat in room divided by energy released in combustion.
40 lbs per day burned in the Chubby has ALMOST ALL THE ENERGY going into heat in the room. You cannot do better than that with the world's largest stove! At very high rates, yes, the big stove will win. Perhaps Fire is in this regime. I was just questioning the sanity of the Chubby /DS comparison on a per pound burned basis.

Greg,
This is AGREED. The Chubby is an excellent choice when the energy needs are 40 lbs per day. At 100 lbs per day the situation is better served with a BIG stove.
Lobster.

lobsterman wrote:

franco b wrote: A hopper can also help in the burning of volatiles by partially coking the fed coal and capturing the heat normally wasted by feeding cold coal in a batch.

Let me put a myth to rest here. The heating of coal in a hopper does not come for free-- it takes energy to do that, in fact the same amount of energy if the coal was heated to the same temperature in the firebox or in a hod on the floor. Anthracite has an extremely low percentage of volatiles so not much to be gained there either.

Do you have proof of this , I think think the volitales account for something like 20% of the heat from coal. With the hopper the gasses come off at a rate they can be burned.

Oh sure, this one is known. Look anywhere, for example:
http://www.engineeringtoolbox.com/class ... d_164.html
I learned about this because I have some cannel coal (rare) which is up to 60% volatile compared to about 5% for anthracite. Anthracite is almost pure carbon. That is why it is hard to light.

Anyway, I am going to sign off this thread, it is not fair to Fire to steal it, and I will look forward to reading about his coal usage and the performance of the DS.

lobsterman wrote:

franco b wrote: A hopper can also help in the burning of volatiles by partially coking the fed coal and capturing the heat normally wasted by feeding cold coal in a batch.

Let me put a myth to rest here. The heating of coal in a hopper does not come for free-- it takes energy to do that, in fact the same amount of energy if the coal was heated to the same temperature in the firebox or in a hod on the floor. Anthracite has an extremely low percentage of volatiles so not much to be gained there either.

Mostly agree. The difference is how and where the coal is heated. Assuming the hopper has been topped up at the previous shake, then at the current shake very hot and partially de'gassed or coked coal is fed to the fire, leading to rapid ignition and fewer volatiles to burn,since they have already been partially burned. This leads to a hotter steadier fire than if a cold batch of coal were fed. That hotter fire has a much better chance of burning any CO that has been forming in the already burning mass of coal. When feeding a batch of cold coal the fire immediately cools and depending on the size of the batch can take quite a while to stabilize the heat output again. Meanwhile a great deal of the volatiles go up the chimney along with increased amounts of CO unburnt until enough heat is again established.

The percentage of volatiles in coal is irrelevant, what is relevant is the percentage of heat they contain. While only about 4 percent they make up about 20 percent of the heat in a pound of coal. Just look at your stack temperature when they start burning.

I think the Chubby is a dandy stove. I like the look and the design. The suspended fire pot has the effect of insulating it from the sides with an air gap leading to a hotter fire and better combustion. Running it at its sweet spot as you seem to be doing gets the most out of it. If fed in smaller batches which you may already be doing I think it can do even better.

Ok,IOF,how's the DS Machinenheimer doing ? Is the house showing signs of holding core heat making it easier to heat the outer perimeter ? Is your Mrs. happy about no more icicles in the kitchen ? How is it going over there ? How about a nightcap update for us before you put the little squeazers and you & Ma to bed.

UPDATE!!!

I backed off of the dial this morning to 4. Stove has been sitting at 500* all day the house has been 73* all day. It is currently 27* with a Western wind at 5 mph. Stove is currently 510*, stack is 170* draft is .05"wc and the house is still 73*. MPD on the stove is closed 3/4 of the way.

Stove was just shaken down at 1900 a half hod of coal was dumped into the hopper. It may or may not get a courtesy shake before bed but I doubt it.

Wife still thinks I'm a dork. But she likes the warmth. She especially loves the fact that we still have not paid for an oil delivery this season and I may have bought my last 10 gallons of diesel for the oil tank. I am very impressed with this stove.

I need to buy a trivet for my kettle of water to prevent the water from boiling off too fast.

I don't know half as much about coal as a lot of people on this forum. I rather enjoyed the little debate that has taken place in this thread. There was a lot of information...a lot of entertaining comments. I'm still a newb compared to a lot of people. I spend more time reading than I do answering questions and I only answer those to which I feel are on my level. I appreciate the concern that some of you have expressed. I will probably never fully understand how a baro works or how much coal I'm using or how to figure out the BTU's in a single piece of coal. But I do know that I like putting coal in my stove; whether it be the Chubby I had or the DS I have now, and I love how warm it makes me. And to me, that is all that matters. I know I will never know as much as everyone here. But I'll have fun learning about it and I'll never go back to wood. Coal is so much more fun.

IOF, I think you know a lot considering the short time you'r in the anthracite Club. Stay warm, you and your family for the present moment it's the most important BTU.

I do tend to learn more by doing. But by the same token I tend to ask a lot of questions repeatedly until I understand what I am doing.

I am still amazed that I was able to light the DS with one match and have the fire sustain itself for more than 24 hours. Although, I did feel more confident in lighting this stove; I did ask questions and bugged Coalfire at home with them. But he has been more than gracious to explain things to me even though I probably asked him several times before.

Good report ! Remember,an Old Sage on The Board once said:"As you burn,so you shall learn" (Hope I got that one right!) Stop selling yourself short. Engineers design and calculate for stoves,feed rates and btu's. Guy's named Mongo mine the stuff,get sized and deliver it. The rest of us are drifting somewhere in the middle. 'Ya Know,we're just Dad's,Husbands(Dorks) Mom's,Wives and all the other assorted rabble who just concentrate on keeping the humble abode warm and dry.

I O F..... Glad to see you are enjoying your new stove. You will never have to worry about not having enough heat again. The D S Stove will serve all your needs. Take your time to get used to it. You'll have it down in no time at all. Again, good luck with the new stove.

I think the one thing missing when comparing the Chubby to the DS is how many BTU's where being lost in the fire place? Is it now properly sealed up? They say an inch gap is equal to having a window open so closing that window would make all the difference in the world.


IOF, I'm glad the new stove is working out for you and your family!

When we installed the DS we pulled the top plate off of the throat of the fireplace. We then stuffed the throat full of insulation and then put the top plate back up.

At any rate, update time.

I went to bed last night the stove was 500*, stack was 170* draft was .06"wc, MPD closed 3/4, house was 73* (when I went to bed) with an outside temp of 22* and light winds. Shook down the stove at 1900. I also emptied the ash pan for the first time. Man that pan can hold a lot of ash. There was two days of ash in there but could have probably held another days worth.

This morning the outside temp was 7* with no wind. House was 68.5* Stove was 500*, .06"wc stack temp was 170*, MPD was closed 3/4. Shook down (8 pulls of the handle) at 0600 temp dropped to 450*. I opened the hopper door and this is how much coal it used through an 11 hour burn.


Looks like 1/2 a hopper to me.

I didn't even bother using the coal hod this morning as the noise it makes when being filled wakes up and upsets my 11 month old daughter. So, instead I used this.


The shovel on the right. A 58oz. aluminum grain shovel. Hopper took three shovel fulls. Each shovel full the nut coal was even with the sides. In fact, when I was done filling it the mound in the hopper stuck up higher than the top. I squished the coal down with the lid of the hopper. I'm not entirely sure what that equates to in pound usage or if there is even a way to accurately measure it.



Here is a pic of the hopper completely full.

Also in the second pic you can see the tote I store my coal in. Generally I can fit around 150# of Nut coal in it. However, lately I can only put 100# of nut in it as there is currently 50# of fines on the bottom of it. I'm not entirely sure what to do with all of the fines. I try to burn them but there is just so much of it I feel that if I load the stove with fines my fire may go out. I'm thinking next time I'm scraping the bottom of the barrel (so-to speak) I'm just gonna take the fines and dump them in my compost pile in the back yard.

The house is currently 70* according to my wife.

Just take the fines and sprinkle them in the hopper a bit at a time when you refill. Will burn just fine.