Heat Distribution With the Harman Super Magnum Stoker

A Coal stoker furnace or stove controls most operations including automatically feeding the coal. They are quite similar to any conventional oil and gas units and easily operated for extended periods of time. They commonly use rice coal but may use larger sizes like buckwheat. They can be used as primary heat, supplementary heat or have a dual set up with your existing oil/gas furnace.
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zags5274
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Posts: 15
Joined: Thu. Feb. 07, 2013 9:12 am
Stove/Furnace Make: Harman
Stove/Furnace Model: Magnum Stoker
Location: Sullivan County, NY

Post Fri. Feb. 22, 2013 3:48 pm

I recently purchased a Harman Super Magnum Stoker and would really appreciate some feedback on how to distribute the heat throughout the house. I have a 1354 sq. ft. full basement which has a temperature between 66 and 70 depending on the temperature outside. I have a thermometer on the ceiling where I would like to place a floor register to get the heat upstairs. The temperature by the thermometer is between 76 and 80. The following is a diagram of my first floor.
House.jpg
Rooms 1 and 2 are spare bedrooms that I keep the doors closed and do not heat at the time being. The green box is the stairway that goes down to my basement and the black box is the stove which is also in the basement. The red box was where I was looking to place a floor 6 x 12 floor register to transfer heat with flex duct and the blue box would be the could return with flex duct to the basement floor. I was wondering should I have the cold return in room 1 or 3, or even in a entirely different room? Does the outlined look a solid solution to distribute the heat throughout the house? Is there entirely different solution I should be looking at?

All feedback would be appreciated.

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titleist1
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Posts: 4404
Joined: Wed. Nov. 14, 2007 4:06 pm
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite
Location: Cecil County, MD

Post Fri. Feb. 22, 2013 4:55 pm

Couple thoughts....
I would get a temp reading in each of the upstairs rooms and then look at putting a cold air return in the coldest room(s) with the flex duct to the basement floor or right to the input of the convection blower.

Second thought is regarding your use of flex duct on the supply off the stove. If the temps are anything like what I have on the metal duct in the workshop I would be afraid to use flex (if you are talking about the plastic wrapped insulated flex duct). I really have to measure the surface temp of that duct coming off that stove. I'll do that this weekend.

Thirdly, you should expect to experiment a little to get this dialed in as much as possible. It won't be perfect in the end either, just probably better than it currently is. Remember you are going backward somewhat in the evolution of heating appliances and heat distribution. There was a reason they had a fireplace in each room back in the olden days and it didn't all have to do with a lack of insulation!

Edit to add....is it a possibility to move the stove so it is lined up directly with the stairwell? Run the flue pipe diagonally to the existing thimble? That way the convection blower is directed right up the stairs. Ours is set up that way and the heat heads right up the stairway without any ducting.
I drive a VW TDI, heat my home & workshop with two coal stokers and have two vintage JD diesel tractors....
The EPA just loves me!!

zags5274
New Member
Posts: 15
Joined: Thu. Feb. 07, 2013 9:12 am
Stove/Furnace Make: Harman
Stove/Furnace Model: Magnum Stoker
Location: Sullivan County, NY

Post Tue. Feb. 26, 2013 2:32 pm

Would setting up the Outside Air Attachment for the stove help? I read that the attachment would help because the stove wouldn't be drawing in the hot air.


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titleist1
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Posts: 4404
Joined: Wed. Nov. 14, 2007 4:06 pm
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite
Location: Cecil County, MD

Post Tue. Feb. 26, 2013 6:14 pm

I don't think that will help with moving the heat from your stove to the upstairs rooms. Do you have some temp measurements in the different rooms? Did you try a return vent in the floor of the coldest room?

Is is an option to line up your stove with the basement steps so the air being blown from the stove goes right up the steps? If you look at my profile pic, you can see the flue pipe running diagonally from the stove. That is because the stove is sitting directly in line with the basement steps so the distribution air is heading right up the staircase. The thimble is off to the right of the stove, the diagonal flue pipe heads over to it. I do not have a supply vent, the open stair case provides that. I do have a flex duct on a floor vent in the furthest bedroom. The flex duct runs to the basement floor, you can feel the cool air coming out of that duct. Our basement is not finished however, so I have some flexibility in the set up without worrying about the looks.

Using outside air for combustion may help if your house is "tight" and the stove is starved for air.
Using inside air for combustion means that air has to be replaced and the replacement will come from outside in the form of drafts, air leaks, etc.
I drive a VW TDI, heat my home & workshop with two coal stokers and have two vintage JD diesel tractors....
The EPA just loves me!!

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michaelanthony
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Posts: 3988
Joined: Sat. Nov. 22, 2008 10:42 pm
Hand Fed Coal Stove: Vigilant 2310, gold marc box stove, vogelzang pot belly coat rack
Baseburners & Antiques: Home Sparkle 12
Coal Size/Type: Coal Contractor's stove, a little Kimmels 'nut
Other Heating: Very cold FHA oil furnace
Location: millinocket,me.
Contact:

Post Tue. Feb. 26, 2013 7:15 pm

Hey Zags, lots of good advise here but tell us about the former heat delivery system. Warm air, forced hot water, steam? If you have an air delivery system in place, that could possibly help. I have an 1100 sq. ft. ranch and I added a plenum to the top of my stove and connected it to the cold air return trunk. I can then use my furnace blower to move the heated air around, ( I rarely need to do that, only when it was -15* -20* ) or by chance god forbid the furnace ever came on it will use the preheated air and shut down quickly. 99.9% of the time I just leave the blower on the stove running if it is 20*- 40* outside it is 75*- 80* inside, if it is -10*..19* outside it is 70* -75* inside, not bad for a brick home with ZERO insulation! Unfinished basement as well....only thing on my basement block walls is DryLock, that *censored* is the balls and of course having a coal fire down there helps too ;)
never yell through a screen...you'll strain your voice.

Rigar
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Posts: 857
Joined: Tue. Dec. 04, 2012 6:30 am
Hot Air Coal Stoker Furnace: Keystoker A 150
Coal Size/Type: anthracite rice
Stove/Furnace Make: Keystoker
Stove/Furnace Model: A 150 warm air furnace
Location: central new york (syracuse area)

Post Tue. Feb. 26, 2013 8:22 pm

michealanthony raises a good point.
but assuming you currently have no air distribution system in place...I would consider putting heat supplys where you have the blue boxes(outside walls)...and even a second heat vent in the large room...across from the first.
"cold air"...or return air try to keep centrally..(maybee end of hallway and near your red box on your drawing)

i don't know which way the stairwell is oriented (down from hall area or down from back of large room)...but leaving that door open or closed may have a huge affect on your "system"...
furnaces are jacketed so the "loop" is closed...with no other influences.
btw...that super should heat the house very well
....'Rigar


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michaelanthony
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Posts: 3988
Joined: Sat. Nov. 22, 2008 10:42 pm
Hand Fed Coal Stove: Vigilant 2310, gold marc box stove, vogelzang pot belly coat rack
Baseburners & Antiques: Home Sparkle 12
Coal Size/Type: Coal Contractor's stove, a little Kimmels 'nut
Other Heating: Very cold FHA oil furnace
Location: millinocket,me.
Contact:

Post Wed. Feb. 27, 2013 7:06 pm

here are some photo's of cold air returns. I had to edit because I ran out of time, slow computer. My stove is in the middle of my basement and the flu goes above a fireplace, if it was an outside wall my cold air vents would be the same and I would probably use a joist cavity as a passage way for the hot air to meet my original cold air supply trunk which runs the length of my basement and directly in the center Ironically my furnace was set up with the supply (heat) vents along the center, interior walls and returns along the perimeter, so in essence I reversed that trend with my stove pumping heat out the original cold air vents and that is why I added the other 3, the closet one is hidden by a louvered door and the white ones in the bedrooms are called baseboard vents (home depot 11 bucks each) and take an inch of the floor space. Each home is different, yet we have some simularity's and the same goal. My stairwell is on the far right based on your drawing and adds to the return value, it hits me in the face when I'm going up the stairs and only proves what others have told me. "need to move the cold air so the warm air can replace it."
Good luck Mike.
Attachments
SANY0006.JPG
this is a cold air return in the closet centrally located
SANY0010.JPG
this is were the closet cold air return meets the stove
SANY0008.JPG
these are cold air returns in my bedrooms and by your drawing they would be room 1 and 6
never yell through a screen...you'll strain your voice.

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titleist1
Member
Posts: 4404
Joined: Wed. Nov. 14, 2007 4:06 pm
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite
Location: Cecil County, MD

Post Thu. Feb. 28, 2013 1:05 pm

zags5274 wrote: The red box was where I was looking to place a floor 6 x 12 floor register to transfer heat with flex duct
I'd stay away from the flex duct on the supply side of the stove. Here is a pic of the plastic housing on the thermometer I put in the airflow off a T about 2' from the top of the stove that's in the workshop... :shock: The mag temp gauge hit 325* on the side of that pipe.
IMG_0041[1].JPG
melted plastic thermometer housing
I drive a VW TDI, heat my home & workshop with two coal stokers and have two vintage JD diesel tractors....
The EPA just loves me!!

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eelhc
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Posts: 204
Joined: Sat. Oct. 25, 2008 9:02 pm
Stove/Furnace Make: Harman Magnum Stoker

Post Thu. Feb. 28, 2013 11:42 pm

Check out what I did with my Harman Magnum:

Harman Magnum Stoker Installation

I would keep it simple and pull air from the warmest room now and push hot air to the coldest room.

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2001Sierra
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Posts: 1845
Joined: Wed. May. 20, 2009 8:09 am
Hot Air Coal Stoker Stove: Keystoker 90 Chimney vent
Coal Size/Type: Rice
Other Heating: Buderus Oil Boiler 3115-34
Stove/Furnace Model: Keystoker 90 Chimney Vent
Location: Wynantskill NY, 10 miles from Albany

Post Fri. Mar. 01, 2013 1:28 pm

2001Sierra wrote:I connected a the suction side of a Panasonic FV-20NLF1 fan to the keystoker output flange I welded on the top of the stove. This pulls the air upstairs with the help of the 250 CFM convection fan Keystoker installed on the back. I hooked it up to the cool contacts on my thermostat upstairs trough a RIB Relay In A Box, on the normally closed contacts. When the upstairs calls for "Heat" on the cold contacts it opens the contacts which turns the fan on. When temp is met the contacts close allowing the room to cool. Reverse logic but with the Delta T of thermostat at .7 degrees the rooms stay pretty stable, which is perfect for slow coal. The Coal-trol maintains the basement temps, and when upstairs is calling for heat the basements gets less, and the Coal-Trol kicks in to catch up. The front convection vent is still open but when upstairs is running a majority of the heat is captured by the Panasonic blower. A Redneck furnace set up.
Picture of stove on right does not show recently welded in duct ring.

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