Harmon Magnum Usage

GAMESNIPER · Post by **GAMESNIPER** » Wed. Dec. 30, 2020 9:07 am

Hi guys i have a Harman Magnum Stoker I bought new back in 2008. So Far no problems yet besides a new set of grates and piece of glass for door.My question is how many pounds of coal will it burn in 1 hour at maxium feed Does anyone know? Answer would be Appreciated.
Thanks Gamesniper

Post by **StokerDon** » Wed. Dec. 30, 2020 9:16 am

Welcome to the forum,

If I remember correctly, the Mag Stoker puts out 85,000 BTU. Divide the 85,000 BTU by roughly 12,000 BTU coal and you get 7.083 pounds per hour of coal feed. This is a rough figure but should be close.

-Don

McGiever · Post by **McGiever** » Sat. Jan. 02, 2021 5:38 pm

2008...is that a SUPER Magnum??

If it is a SUPER, then you can get 105,000 BTU/hr. max. output.

Post by **Lightning** » Sat. Jan. 02, 2021 6:51 pm

StokerDon wrote: ↑
Wed. Dec. 30, 2020 9:16 am
Welcome to the forum,

If I remember correctly, the Mag Stoker puts out 85,000 BTU. Divide the 85,000 BTU by roughly 12,000 BTU coal and you get 7.083 pounds per hour of coal feed. This is a rough figure but should be close.

-Don

If 85000 is output BTUs then with a factor of 10,000 BTUs per pound (efficiency) it would be closer to 8.5 pounds per hour. Would be my guess. Not trying to split hairs though

I use 10000 BTUs per pound for most calcs to factor in efficiency which is probably a bit optimistic lol.

Post by **StokerDon** » Sat. Jan. 02, 2021 8:12 pm

It's not a boiler so it's over 12,000 BTU per pound. I was being conservative calling it 12,000 even.

-Don

Post by **Lightning** » Sat. Jan. 02, 2021 10:10 pm

StokerDon wrote: ↑
Sat. Jan. 02, 2021 8:12 pm
It's not a boiler so it's over 12,000 BTU per pound. I was being conservative calling it 12,000 even.

-Don

It wouldn't matter if it's a boiler, furnace, or stove.. Output BTUs will be a percentage less than input BTUs because of efficiency, 80% (10000 BTUs/pound of usable heat) is being generous..

Where is Isayer? lol

Post by **StokerDon** » Sun. Jan. 03, 2021 9:23 am

Lightning wrote: ↑
Sat. Jan. 02, 2021 10:10 pm
Output BTUs will be a percentage less than input BTUs because of efficiency, 80% (10000 BTUs/pound of usable heat) is being generous..

I don't know where you got that from but I've never heard it before. With a boiler you figure it like this;
12,250 X Pounds per hour minus 10% for bone, rock, shale in the coal. Minus the boiler efficiency (80% to 90%) = output BTUH. That is the standard.

I know there is one for hot air furnaces too but I don't know what it is. It has something to do with coal vs. bonnet temperature. There has never been a standard for stoves that I know of.

-Don

Post by **Lightning** » Sun. Jan. 03, 2021 10:43 am

Like you said, 10% for ash and another 10% is losses with combustion efficiency and heat going up the stack. This is very optimistic though. You translated his input pounds by using the output of 85000 BTUs at nearly 100% efficiency by using 12000 BTU per pound. My using 10,000 BTUs per pound factors in some of those losses that you described and is just a different path around the same hill.. That's all, no biggie, carry on

GAMESNIPER · Post by **GAMESNIPER** » Tue. Jan. 05, 2021 11:05 am

Hi guys thanks for replies.My stoker stove is the magnum the old style not the new style they sell today. I was just curious on coal usage they figure on burning max feed for 1 hour