How High Is TOO High of the Outside Temp of There Stove

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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jlentz1006
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Joined: Mon. Nov. 04, 2013 4:08 pm
Stove/Furnace Make: Reading
Stove/Furnace Model: Juniata

Post Mon. Nov. 25, 2013 6:06 pm

Im trying to mess with fan speed on my reading juniata to get hotter grate temps at full burn ive had the outside of the side of the stove at 570 degrees I cant find anywhere on a reading on if thats too hot by the way that was near the top middle of the stove

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dcrane
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Hand Fed Coal Stove: Crane 404
Location: Duxbury, MA./Hanson MA./Brockton, MA

Post Mon. Nov. 25, 2013 8:28 pm

just looking at it I will let you know if you exceed much over that those large sides/top will distort in time (i cant see any structural bends, im not sure if their is reinforcements gussets of any kind inside or to what degree they tested)... I assume that outside wall your gauge is on is NOT the combustion chamber wall??? (so I find that temp of 580 on a non-combustion side to be VERY high and probably not made to withstand it)... if those outside walls are simply heat exchange walls they are most likely tack/spot/stitch welded (in which case at 600 degrees your asking for trouble in-between those welds).

jlentz1006
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Posts: 42
Joined: Mon. Nov. 04, 2013 4:08 pm
Stove/Furnace Make: Reading
Stove/Furnace Model: Juniata

Post Mon. Nov. 25, 2013 8:39 pm

Hmm okay right now the hottest spot of the stove is about 480 right now on a non combustion wall of the stpve but nothing is warped


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titleist1
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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 Mon. Nov. 25, 2013 9:40 pm

the magnetic gauge on the side of my stoves routinely hits 600* when it is firing hard on the coldest nights. what thickness steel is used in your stove?
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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dcrane
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Hand Fed Coal Stove: Crane 404
Location: Duxbury, MA./Hanson MA./Brockton, MA

Post Tue. Nov. 26, 2013 6:08 am

titleist1 wrote:the magnetic gauge on the side of my stoves routinely hits 600* when it is firing hard on the coldest nights. what thickness steel is used in your stove?
Is the side of your stove the combustion chamber or blower shroud/heat exchanger? Harman is certainly a heavier gauge than the posters stove (at least the ones prior to the "take over"), 600 is generally the max point of recommendation on a combustion chamber top (its very hard to get those temps on any secondary layer of the stove and if you did... something is warping someplace I assure you!)... the combustion chamber would need to be at 800 to enable a blower shroud to reach 600.

On the posters stove those side panels are HUGE fields of flat steel sheets! :fear: gauge wont save those from distortion after 600 degrees unless they built in a gusset system or supporting stiffeners of some kind.

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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. Nov. 26, 2013 8:16 am

my temp gauge is on the combustion chamber wall - 1/4" thickness. magnetic gauge is located on the top front corner of the side, just around the edge from the door. I found that to be the hottest spot I could get the gauge on. warping of combustion chamber walls has not been an issue in 20+ years. only warping I ever experienced was the baffle plate inside the firebox. I didnt realize in the early years of the learning curve the amount of fly ash that was up there. it wasn't cleaned well enough before summer storage. over time that plate flaked away and being thinner didnt handle the heat and warped. the baffle plate is something I always check on used stoves.

interesting that I've never seen the 600* number used as a max temp although they do mention that if you see the steel or exhaust pipe glowing you are overfiring! :shock:
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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SMITTY
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Stoker Coal Boiler: Patriot Coal - (custom built by Jim Dorsey, Taunton MA - RIP 4/18/13)
Hand Fed Coal Stove: Harman Mark III (SOLD!)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler
Location: West-Central Mass

Post Tue. Nov. 26, 2013 10:31 am

A faint, dull red glow usually begins around 760°, at least according to my infared thermometer. It's plainly visible in bright light over 850°. Bright red is over 1,000°. When you start getting into WHITE hot, that's pushing 2k°!! You'll damage something at or near that level, I'd guess. ;)
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jlentz1006
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Posts: 42
Joined: Mon. Nov. 04, 2013 4:08 pm
Stove/Furnace Make: Reading
Stove/Furnace Model: Juniata

Post Tue. Nov. 26, 2013 12:18 pm

Its never that hot its a reading juniata not as heavy duty as a Harman im getting cold air pulled through the basement doors which are metal an no door at the bottom of the steps making it hell to heat my stove but at max firing its 475 or around there on the outside I guess I need to build a door and insulate around it an put an insulated door to the attic im getting cold air in the basement an hot air going right through and old wooden door to the attic making it impossible to heat my stoves always burning high when its 30 and less house only gets to 70 degrees going through quite a bit of coal

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