How Low Will a Harman MK 1 Go in Firing Rate?

Where I live in SE CT the weather and temps vary all over the range in the winter so might be 42 during the day and 24 at night with wind.
Stove top temps for my small woodstove can be as low as 250 on a mild day and 550-600 on a bitter cold night. It is listed as 64k btu/hr. but that is pure fantasy as is the 8 hr. burn time. It is the same approximate size as a Harman MK 1 so I would think similar heat output with the difference the wood stove has a large temp cycle and the Harman just chugs along. Am I missing something?

My Mk I with a good draft has gone as long as 22 hrs on a low burn.

Wood vs coal is no comparison. Why do you think we're all here!

I'm in the process of installing a Mark I in DK's man cave. Remember, the Mark Series has a baffle or fake ceiling which make getting an accurate stove top temperature reading next to impossible. Based on my Mark II, I know I'll be able to run the Mark I at 125* or 150* as measured on the upper right edge of the load door but I expect it to go even lower. I'll have to play with it. I expect to get a 12 hour burn using pea coal and because of the nature of coal the temperature will be steady throughout the burn. I will be able to leave the house with the room temperature at 75* and when I return hours later, it will still be 75*.

On the Mark II my longest burn was 30 hours and I had fuel for a couple of hours more. I left with a room temperature of 75* and got back the room was still 75*. In my humble opinion, coal wins hands down.

I've been firing a Mark I for about 12 years now if memory serves...?? It routinely gets 24 hours without even trying, and 36 hours is more like it on a full batch of coal and just raking, not adding any. This is why, when I read the raves about how great the old baseburners are, and how long they burn, I just wondered what's the big deal- my entry level Harman I always was capable of that since day one- and has a fan in it to boot.

At end of season when I decide to shut it down, I may fill it one last time at night- it burns the entire next day without adding any coal, and just raking, on the lowest setting 3/8 turn open on the ash door draft knob. 2nd day in the morning, guess what, it's still burning and heating the house. It will usually then go out usually sometime during the 2nd day by late afternoon. The funny thing about it is, until it's finally OUT, I can still catch the fire if need be, by opening it up, adding some coal judiciously to the spot of fire that's left, and it comes back to life in no time.

Wood is great if someone else is delivering it cut/split/stacked/covered at about $65 a cord, or giving it away for free, or if you can find standing dead trees that are hardwood alread seasoned, and small enough diameter to cut 6 cords-8 cords a year without splitting it, to fit in your stove with minimal labor. That doesnt' exist- processing firewood is labor and cost intensive- at $150-$175 a cord locally, wood is a cost loser to coal, hands down. That may change if Obama continues to strangulate the US coal industry, remember what he said about coal mines, by design they will be bankrupted. We'll see. Keep your wood burner in the wings as a spare, and go with the coal stove for now. You'll save a truckload of money over the next 5 years at today's coal prices.

coalcracker wrote:I've been firing a Mark I for about 12 years now if memory serves...?? It routinely gets 24 hours without even trying, and 36 hours is more like it on a full batch of coal and just raking, not adding any. This is why, when I read the raves about how great the old baseburners are, and how long they burn, I just wondered what's the big deal- my entry level Harman I always was capable of that since day one- and has a fan in it to boot.

At end of season when I decide to shut it down, I may fill it one last time at night- it burns the entire next day without adding any coal, and just raking, on the lowest setting 3/8 turn open on the ash door draft knob. 2nd day in the morning, guess what, it's still burning and heating the house. It will usually then go out usually sometime during the 2nd day by late afternoon. The funny thing about it is, until it's finally OUT, I can still catch the fire if need be, by opening it up, adding some coal judiciously to the spot of fire that's left, and it comes back to life in no time.

Wood is great if someone else is delivering it cut/split/stacked/covered at about $65 a cord, or giving it away for free, or if you can find standing dead trees that are hardwood alread seasoned, and small enough diameter to cut 6 cords-8 cords a year without splitting it, to fit in your stove with minimal labor. That doesnt' exist- processing firewood is labor and cost intensive- at $150-$175 a cord locally, wood is a cost loser to coal, hands down. That may change if Obama continues to strangulate the US coal industry, remember what he said about coal mines, by design they will be bankrupted. We'll see. Keep your wood burner in the wings as a spare, and go with the coal stove for now. You'll save a truckload of money over the next 5 years at today's coal prices.

Well using the calculator here and my local costs are as follows,
coal by the ton delivered 335.00/ton 80% 17.45
coal by the bag at lumberyard 10.50/50 lb. bag 80% 21.88
Wood 190 a cord cut split delivered 70% 9.87 (I adjusted the BTU content to account of the red and white oak I burn)
oil 3.75/gallon delivered 83% (my boiler) 32.58

So I think cost is a local thing rather than universal. I am looking at coal for a halfway point between fuel oil and wood with closer to the convenience of oil with less work by me but it is not the cheapest in my case.

The Mark I is rated at 48k BTU's ... and that is also a fantasy, unless you get the sucker one step below glowing orange. That said, it heated this drafty assed house for 3 solid seasons. Very impressive given it's really small physical size. It struggled in January though - 65° was the most we'd see in here with it sending close to 400° up the chimney .. WITH the convection blower going.

I measure temps on the Mark series at the middle of the sides - this is the hottest part, depending on how far along the fire is (closer to the top will be hotter early on). I've had it down to 230°, and probably could've went lower ... but my line of thought on that is, why burn if you need to idle that low? Coal is cheap, but it ain't FREE.

well I'm sitting here and it's in the low 20's outside, and 72 in my house, with the Harman simmering away, and the fan shut OFF. I'm in bare feet with a T-shirt. I have 1 ton of coal left over from last year in the bin, and had another 2 ton delivered this year on top of that. That was $200 a ton. I'm good to next year this time and longer, most likely what's in the bin will heat my house until April 2015.

on the other hand, you need to get cutting down trees outside now in this weather, and transporting by truck, and splitting/stacking, and feeding your wood stove. Have at it. I've been there, done that, because my Dad burned wood until I was 33 years old, and I had to help him get the wood.

I'm not burning coal only because it's cheaper, I'm doing it because it's a mighty crap easier too.

even if you have it delivered, you'll need about 6 cords this year, and another 6 cords next year, to equal the 3 tons of coal I have in the shed now, to heat a house, because while your BTU calculator doesn't tell you is this- YOU CAN'T FIRE DOWN A WOOD STOVE to a low simmer for long periods of time, you'll plug up the chimney with creosote and cause a chimney fire, or have to clean it every 2 weeks. And even when turned down all the way, that wood will burn up in no time.

good luck with that....really.

the BTU calculator is not real world. In reality, you need 6 cords of wood, to equal 2 tons of coal, because of moisture content and the wood suppliers, mix in softwood with the cut. On the coldest winters, the ratio is 2.5 tons of coal, to 8 cords of wood. Ask me how I know.

if you cut the wood yourself, add in the cost of chainsaw gas, 2 stroke oil, chain sharpeners, plugs, new chains, gas in your truck, tires, time. Even a minimum wage job at Wendy's flipping burgers pays $7.50/hour but while you're getting firewood, you make nothing, and spend money. We were putting $20 a day in my F-150 before the brother-in-law woke up and realized, this wood burning is getting him nowhere in his house heating. What he put in my truck everyday for gas, to get wood, I was heating my house with for 5 days with coal. And he then had to bust nust, cut down trees in 1 foot of snow in the woods, drag them to my truck, load them, unload them at the house, then buck them into sections, split, stack, then feed the stove. Not to mention the chainsaw gas, oil, new chain, and I had to rebuild the chainsaw carb, and put new mounts on it.

are you getting the picture yet ?

what my nephew spent on a new Husky chainsaw, $800, will heat my house for 2 years. What he spent on a chain, $45, will heat my house for 11 days. He is also now waking up and got a free coal stove that needs window glass and a tune up.

see it's a hole you can't dig out of. You can't get ahead burning $190/cord wood, when gasoline is $3.45 gallon to get it, but coal is only $200/ton- delivered. You need 2 cord of wood in real life, to equal a ton of coal. NO labor involved on your part with the coal.

Let me just say this- if God made a better way to heat in winter than coal, he kept it to himself. The only thing better is the sun, or maybe a volcano.

If you read his post you will realize that coal will cost 335 delivered and the wood 190 delivered. Your conclusions are only valid for yourself and your local conditions.

Coal wins hands down as far as the convenience & the nice even heat it puts out all day long. Based on what I've used so far this season it looks like coal will be a little more expensive for me & the house will be a bit cooler. If I kept the house as warm as I did with the woodstove coal would be much more expensive. Much less work & no derelict wood suppliers to deal with but it is more expensive for the same heat level in my old house.

coalcracker wrote:ps- the BTU calculator is not real world. In reality, you need 6 cords of wood, to equal 2 tons of coal, because of moisture content and the wood suppliers, mix in softwood with the cut. On the coldest winters, the ratio is 2.5 tons of coal, to 8 cords of wood. Ask me how I know.

I won't bother to ask because after heating this old place with wood for 30 years I know it's BS. 6 cords of wood was average usage for a season, slightly more if it was brutally cold. That was burning from October into early May & we were toasty warm (high 70's). I'm averaging a 40lb bag+ a day right now to keep the house in the low 70's if it's 30*F outside. When it starts dropping into the teens I expect that usage to go right up.

As far as wood cost goes I buy measured cords in the spring for $150 a cord delivered.

I don't think anyone will argue that free wood isn't free and that coal is a no brainer as a choice between the two.

That's why we're here.....

get cutting...you're chainsaw and splitter and freezing weather awaits....

meanwhile, I'm gonna crack another Miller high life...

coalcracker wrote:... meanwhile, I'm gonna crack another Miller high life...

Maybe it's time to stop posting while drinking?? That was $150 a cord cut/split/delivered in the Spring. This time of year I'm burning the wood in my shop not sourcing it. It would also be nice if you'd stop trying to pass off gross exaggeration & personal opinion as fact.

By the way how about telling us how many sq.ft. you are heating with that Mk1 & 2 tons of coal??

My father heats with wood and I heat with coal. In our situations the only advantage I have over my father is a little more convenience. Dealing with cutting and splitting wood is not for everyone, but I think some people try to make the wood life out to be worse than it is. For a very reasonable price my father can get about 7 cords worth of logs delivered to the house and then he cuts them with his 30 year old chainsaw that until recently hasn't needed anything but some chains and an ocassional bar. If something ever happens to coal, I will have no problem going to wood.

mmcoal wrote:My father heats with wood and I heat with coal. In our situations the only advantage I have over my father is a little more convenience. Dealing with cutting and splitting wood is not for everyone, but I think some people try to make the wood life out to be worse than it is. For a very reasonable price my father can get about 7 cords worth of logs delivered to the house and then he cuts them with his 30 year old chainsaw that until recently hasn't needed anything but some chains and an ocassional bar. If something ever happens to coal, I will have no problem going to wood.

I heated with wood for decades. If I couldn't get coal, I'd go back in a heartbeat. Nothing wrong with burning wood. I like the smell, I really like a fireplace (don't have one right now I can use). If I were retired and had free wood, I might just switch back.... Naw... I love burning coal way too much!

dj

coalcracker wrote:well I'm sitting here and it's in the low 20's outside, and 72 in my house, with the Harman simmering away, and the fan shut OFF. I'm in bare feet with a T-shirt. I have 1 ton of coal left over from last year in the bin, and had another 2 ton delivered this year on top of that. That was $200 a ton. I'm good to next year this time and longer, most likely what's in the bin will heat my house until April 2015.

While no one is doubting you, again that is extraordinarily low and due to the configuration and size of your house. The average person can expect to use a lot more, about 4 to 5 ton per 2000 sq. ft.

what my nephew spent on a new Husky chainsaw, $800,

Either your nephew is in the tree business or he bought something he doesn't need.