Keeping My Stove Going While At Work

This is my first season with a hand fed coal stove. I have the Harman Mark II Stove. I use what has been told to me by many as the best hard coal there is called Blaschak. I use the Pea size. My biggest problem is maintaining a fire while I am at work. It is 9 hours from time I leave till I return. Dealer said I should get a min of 12 hours. When I come home it is either too low to get it going again or has just a little red and a lot of burnt coal to the sides. Not sure if it is all ash or if it is unburnt coal as it is gray shale in color. I know I have excellent draft as it roars when I can be home and attend to it. In fact usually it is too hot(87) in my place when I fire it up. My dealer said I have my draft knob that is on the ash door open too much and then showed me it should be only turned like 1.5 turns from closed. I think I tried this once and fire went out as probably too low but then I think maybe I banked the fire too early before having a hot enough fire. He says hard coal needs very little draft. I am tired of rebuilding and about ready to sell the thing. What am I doing wrong here? Thanks

He was right about the dial on the ash door. I keep mine at 1.5 turns out from fully closed most of the time, but I vary it from 1.25 in warmer weather (like now), to 2 turns open when its in the single digits to below zero for an extended period. If you have a stronger draft, this will require less of an opening than I use .... and the opposite if you have weak draft. My chimney typically runs at .04" -.05".

Also, how much you shake will also determine burn times. I shake until the ash pan becomes visible from the glowing coal bed, then I poke with a steel rod to break up any "bridging" of the coal, then shake some more. When the pan is nice & bright under there, then I start loading the coal in layers until it's full to the top of the firebricks, and above the bricks in the center. Pile it on. Coal likes a deep bed.

From what you describe, sounds like the dealer is right. Give it less air.

Personally, I think the Marks run best with nut size, but that's just my preference.
Are you running your stove filled right to the top of the bricks?
When I first started burning coal, I had similar mediocre results. From burning wood for 30 years,
I was disappointed.
Then, I started burning coal the way you should. FILL the box. It will run so much better.
Mine must be similar to Smitty's.
I run it between 1-1/2 to 2 turns usually. That is with the pipe damper closed about 7/8 of the way.
Draft is pulling around .03-.04
If you aren't controling your draft, via Baro, or manual, and you have your lower control open more,
I would think you would get pretty short burns.

Obviously there are more factors, but those are the primaries, imo.
keep it full
control the draft
monitor your stove and stack temperatures.
Once you see it "click", you'll really like it.
try a couple of bags of nut.

Is this you jingles? If so its about time you ask the professionals instead of torturing me at work!
I would tend to agree, however I think hard coal would require more draft than bit, due to its lower percentage of volatility. Also an addition of a barometric damper or manual damper in your flue would allow you to have more control and longer burn times

uffbros wrote:What am I doing wrong here? Thanks

Sorry to be so long winded but...

You're probably not doing anything wrong - you just haven't found the balance between your draft and your coal in order to generate the burn you want. I'm a big believer in themometers. Do you have one on the front of your stove and one on your chimney connector pipe? Those temperetures are a good indicator as to how much fire you have given the amount of air input you have the stove set at. The more air the hotter and quicker the burn. I burn a Mark II and I use Blaschak pea and Reading nut coal. I mix the sizes to get range coal.

You need to discover the lowest air setting you can use that allows you to have the length of burn and heat production you want. For example, with an outside temperature of 27* I know I need to have a stove front temperature of 200* to achieve a room temperature of 76* and to achieve that stove front temp I open the air valve to 2/3s of a turn. At that setting my fire will burn for 8 or 9 hours. Use the themometers mentioned to find your air settings and their cooresponding temperetures. I keep a log so I don't have to keep relearning things.

Another thing I’d point out is that your stove won’t always have the “blue ladies” (flames) dancing. Sometimes your fire will look quite dead with no flames at all but deep in the coal bed you will be producing heat. The ultimate goal is to produce heat with the least amount of coal used. That’s the important thing – is your fire producing heat? Your stove front thermometer will show you that. At a setting of just under ½ I never see the blue ladies but I know the heat is being produced by the thermometers. Take some time and find your air valve settings in relation to the temperatures and burns you want to produce. I hope to have given you somethings to think about. Lisa

I have a temp gauge on the pipe but that is all. I can make my place 90° if I want..Thats not a problem. It's maintaining the fire while I'm away that I can't get. Dealer says I should get at least 12 hours if I open the air control on ash door 1.5 turns..That isn't very much from looking at the gap at that setting but will try it as soon as I get it going again...I am having a hard time getting it going with charcoal bricks. It starts off great but the wood doesn't seem to want to catch today..same wood as I been using. Getting real discouraged. Those of you who use charcoal to start your fire..Do you let them burn for awhile before you add the wood? I get great flame with them and as soon as I add the wood it dies in 2-3 minutes..I had better luck with cardboard.

Thank jingles..You should be here right now.......Others with same stove say the lower air is the secret basically. If I ever get it going again I'll try it as I'm back to work then. Where is snap when ya need him????Go hard!!!!!

I can tell you 1thing..You'll never see me going to jail for arson..I couldn't start a fire if I tried...Because I have.....lol...lol There's always natural gas.Turn the dial and your done.

uffbros wrote:I have a temp gauge on the pipe but that is all. I can make my place 90° if I want..

and you can make your car go 120mph, but you'll use twice as much gas as when you are going 55..

dealer said I should get at least 12 hours if I open the air control on ash door 1.5 turns..That isn't very much from looking at the gap at that setting but will try it as soon as I get it going again...

You might get 12 out of it, if you do not have a ripper of a fire going.
Today it is very mild here (40's), I filled mine this morning (7:30), and now (6:20pm) the side of the stove is around 400,
and the fire is still going great (with the ladies), I won't have to add and shake until I go to bed at 10:00 or so.
But I will add some around 8, so that I don't have to put as much on at 10 or 11.
If you put too much on, it may stay going, but your stove temp will dive bomb.
And it will take quite a will to get back up to temp.

My stove pipe damper is 7/8 closed, and the lower draft control is open about 1-1/4.
Cold days (single numbers), it's opened maybe 2 turns, or a tick more.
And obviously, I am adding more fuel. I want the stove at 550-600

Getting real discouraged. ..I had better luck with cardboard.

Don't get discouraged! Like I said, once you 'get it', coal is pretty easy to use.
BTW.
Cardboard is crap for lighting a fire.
You may be just having a hard time ESTABLISHING your good bed of coals.
It's easy to get a ripper going, but that doesn't mean you have a good "coal fire" going.
The thing I noticed about coal more than anything, is that it doesn't change really fast, to small adjustments.
You can turn your draft control a 1/4 turn, and you may not see the results for an hour.
You need two thermometers, imo. one on the stove, and one on the stack.
Learn what it likes, and you'll be gold.

***UPDATE*

It is now 83° in here..nice blue flame going thru the coal..I put the thermometer on side and it is 400°. I have the ash door draft at 1.5 turns open. Note I don't have any dampers at all in my pipe to the stainless steel chimney I guess they are called. I will fill the box before bed and see what we look like in the morning before I head to work. Thanks for all the replies.

Jingles, it s been warm today and the air is heavy, better get out the heavy artillery... You might as well go down to sheetz and get some gas to get that baby going! what did I tell you about this website, lots of good information. Just keep in mind, if you do ever go to arson, I could use a good plumber... can you say 5.25 a month.

You should have a barometric damper. It will help with controlling the stove draft and therefore coal consuption, and therefore money.

uffbros wrote:Note I don't have any dampers at all in my pipe to the stainless steel chimney I guess they are called.

Most will agree with me, you should have a barometric damper (also known as a draft control) to reduce your chimney draft to the proper level. Otherwise you can burn a lot of coal in a short time to get adequate heat from the stove, because a lot of the heat just goes up the chimney. Been there, done that. There are lots of threads in the forum discussing baro dampers. You should easily get 12 hours out of that stove.

My pipe coming off the stove is a 6" and goes up 30" and then goes into a 8" pipe up thru the ceiling out to the stainless steel chimney. What part do you install a barometric? Towards the top or in the middle? I would need to know as I would need either the 6" or the 8" depending on where the install goes.