Am I Not Burning Stove Hot Enough?

This is my first year burning coal. I have a Mark II on the fireplace hearth in my living room. It is heating 2,000+ sq ft. My house was built in 1979 and only has electric heat. I have the electric heaters set to 60deg and the ones upstairs kicked on last night. Should I be burning my stove hotter? On average I have the air knob at .75-1.0 turn and stove temp runs around 275 - 300. I see a lot of people here running stove temps of 400 - 500. My only concern with burning hotter is losing the fire. I tend the stove every 12 hours. Yesterday when I got home (stove set at 1 turn all day and room temp was 67) I shook it down and the fire dropped to 2/3 - 3/4 of the fire brick showing. I am afraid if I turn it up it will burn out. My baro is set at .06. Could I be shaking too much ash out causing a faster burn?

Are you getting every last piece of coal in the stove that you can? Pile it high and deep...and run the stove up to 500 if you need to. You could probably back down the baro a little, 0.04-0.05 worked fine for me.

-Rob

Just pile the coal higher if you are only flat to the top of the back fire bricks...
The pile is good for another 15-20#...
I used a grain scoop to better place the coal when I had a Mark II...
Went with a bigger stove, DSM Basement #4, because I was adding coal every 8 hours to the Mark II...
I could fit about 80# into the Mark II when I piled the coal...
Now I get 12+ hour burns between tendings...
Just add coal to the hopper...
The DSM holds about 180# of coal...
And yes you need to burn it hotter if your house is not warm enough...
You will need to add coal more often...

I have the draft on my Mark I set at -.04" to -.05" of WC. I fill the firebox with as much coal as I can possibly fit in, all the way up to the loading door lip in the front and banked up past the firebrick in the back, the fresh coal is actually touching the baffle plate. The coal will tend to sink somewhat as it burns. The temperatures are 490 with a surface thermometer on the upper right side of the stove and 250 with a probe thermometer in the stack before the baro. I suspect the thermometers aren't that accurate, so allow some room for error. Air vent is open 1 turn. 12 hours burn time is no problem.

I'm heating about 2000 sq. ft. as well, drafty old farmhouse. The Mark I is too small for the job, but I also use a Fisher woodburner in the fireplace and will be heating with the EFM boiler soon. When temps are in the 40's or above the Harman heats the house on it's own. It sounds like your stove should be producing more heat. What brand coal are you burning?

The most important factor in getting long burn times is to have high quality coal.

When I load it I fill it to the top of the bricks in the back and slope it to the top of the fire brick in the front. I could probably pile it up in the middle to get a little more coal in. I had to add 3 washer to the weight on the baro to get it set at .06 (my chimney drafts very well). I might add another washer this weekend to try to get it down to .04-.05. I am burning bulk Blaschak nut coal. When I reload it takes about 3/4 of a coal bucket to top it off. I also live on top of a hill and it is always windy. Yesterday it was very windy all day.

Get the draft down a little lower & stuff it full!
Blaschak is good, but there are better brands. I'm burning a pea/nut mix (range) right now. The smaller sizes slow the air flow through the firebed and extend the burn time but the temperatures will be lower.
Where do you live?

I am just outside of York, PA. Temps the past day or 2 have been in the low 30's for a high. Yesterday windchill was in the teens.

Burn it as hot as you need it, up to the limits for the stove.. right now you are at a 'moderate temperature'.

In this windy, cold weather, you may have to modify your loading/tending schedule to include adding a shovel full or two just before bedtime, and just before you go out the door in the morning.. Or, if someone is home during the day, toss on a shovel or two in the afternoon..

Personally I'd turn the electric heaters to 50-55*, and let the Mark II do as good as it can.. and if you are chilly when home, open up the air a bit, and get the stove temp up to 550* or so..

I'd definitely mound up the coal in the center.. over the firebricks in the back,, it won't burn up on top of the firebricks, it will only fall off into the coal bed as the coalbed drops down.. LOAD 'er up !!

Whatever works for your instalation.

GL

I run a Mark II, right now it is running just under 600, with 225 on the stack above baro. It has been really windy here the last couple of days, so I have been eating a little more coal with this one. Capecoaler and LSFarm both kept telling me to pile it up higher and higher, but the wood burner in me was not dead yet. Once I started piling as much as I could fit in there, it started burning like they both said it would. Listen to those guys, load it up, liven it up good and proper, your vents sound good, but drop the baro to .04-.05. At least this is what is working well for me even with the junk Reading coal.

What size coal are you using?

I've taken to stove coal in the last few years to get the heat and time I need out of my Mk I.

Typically, I can get 12hrs out of it with the knob open 1.25 turns.

Loading it up as high as you can get it is key.

cowentz wrote: Should I be burning my stove hotter? On average I have the air knob at .75-1.0 turn and stove temp runs around 275 - 300. I see a lot of people here running stove temps of 400 - 500.

Simple answer - yes, if your stove is not producing the heat you want, then yes you should be burning it hotter. I believe the owner's manual says that 500* or more is over firing the Mark II. There is a lot of wiggle room between where you are now and where you don't want to be - over firing.

cowentz wrote: My only concern with burning hotter is losing the fire. I tend the stove every 12 hours. Yesterday when I got home (stove set at 1 turn all day and room temp was 67) I shook it down and the fire dropped to 2/3 - 3/4 of the fire brick showing. I am afraid if I turn it up it will burn out. My baro is set at .06. Could I be shaking too much ash out causing a faster burn?

Learning the balance between the outside temperature, the draft of your chimney and the amount and type of coal you are using to produce the heat you want is the art of heating your home with a hand fed stove.

Both Wood N Coal and I use range coal (a blend of pea and nut) to get maximum heat over a longer period of time. Yes, shaking out too much ash may cause a faster burn but I suspect you have more of an issue with the draft. A Harman filled to the top of the fire bricks with nut or pea at 1 turn should burn for 15 or 16 hours without attention and there should be plenty of fire left to recharge and start again. How did you come to set the baro at .06? Did you calibrate that with a manometer? A chimney with that sort of setting on the barro must literally be humming. Does the baro ever open? If not you are pulling air only from the fire and the baro is doing nothing for you. If you didn't set that with a manometer, I'd drop that back to .04 like one of the earlier posters said and I'd see about getting a manometer as soon as I could.

cowentz wrote:I shook it down and the fire dropped to 2/3 - 3/4 of the fire brick showing. I am afraid if I turn it up it will burn out.

When I shake my Mark II after 12 hours I expect to see the fire drop a good 3 or 4 inches. It means the fire has been burning well. Always start a recharge with a hot fire with a lot of Blue Ladies Dancing, aka flame. When I shake my stove I close all the doors and watch the air intake value. When it starts to glow I stop shaking, sometimes I shake more, sometimes less. If I meet any resistance to the shaking I go away and come back later. That's a sign that there is more unburnt coal then ash.

But I don't think it's a question of the ash, I think it's a question of too strong an under fire draft with not enough coal to burn which is making your fire burn hot and quick. I'd look at slowing that down and then I'd fill the fire box to the top of the fire bricks and not worry about it for 12 hours. Yeah, I know that's easier said than done but take the leap of faith. Lisa

The baro was set with a manometer. Before I adjusted it I would see normal draft of at least .10 and wind gusts of well over .20. I have the weight all the way to the center with 3 washers on it to get it to open at .06. I still see wind gust go up to .10 on a rare occasion. The baro does and is open quite often. There are still some times when it is closed though. I have a feeling I am worrying about it too much and I just need to crank it up, fill it as full as possible and not worry about it.

Wow Lisa, very informative I'm going to take a good hard look at my stove when I get home and see if I can apply what you wrote.

cowentz wrote:... I have a feeling I am worrying about it too much and I just need to crank it up, fill it as full as possible and not worry about it.

I agree.. don't worry about it.
You absolutely need to crank it up. I live in the northeast as well,
and yesterday it was so windy the flags looked they were made out
of sheets of plywood..
My Mark was at 500,
today isn't quite as cold it's around 450-475.
275-300 just ain't gonna cut in those conditions.
Don't worry about the stove, it's a workhorse.

I stopped worrying about how many turns my intake was opened
compared to others a long time ago.
It's not doing you any good to think that you "need"
to only open it up 3/4, if you're frezzing.
If you need more heat, open it up.
try a 1/4.... wait an hour or so, and see
what effect it had. It's slow to react to those changes gonna have to be patient.
You may have to go back 1/8th or ahead an 1/8th.
Sounds like you have a grip on everything else... CRANK that sucka!

lowfog01 wrote: I believe the owner's manual says that 500* or more is over firing the Mark II. There is a lot of wiggle room between where you are now and where you don't want to be - over firing.
Lisa

We should clarify that overfiring @500 degrees,
is 500 'stack' degrees, and not 500 'stove' degrees...

500 on a Harman stove is like a car with cruise control on 60....

Dan