Pellets and corn mix in P68?

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Jan 29, 2021
155
VA, east central
I just noticed that the text on the inside of the hopper lid stated that a pellet corn mix could be used in this stove. This surprised me as I have not seen it in any of the documentation that came with the stove. Maybe I missed it elsewhere? Anyone have further info on using a mix?
 
So the operator's manual states pellets only. Maybe the info in the hopper is a generic blurb about what the hopper itself can handle. Seems like a bad idea to do that though if the stove itself is designed for pellets only.
 
In the manual it says
Burning of any fuel other than wood pellets voids warranty
 
This is what it says in my p43 manual dated 2013.
Corn2.JPG
Corn.JPG
 
That's what it says on the first page of the manual Now see page 8 under the heading Caution
in this manual for a P68
If it is too hard to look up here it is
Tested and approved for use with wood pellets ONLY. Burning of any other fuel will void your warranty

SO who is right
 
What I think Johneh is that Harman may have changed its mind on burning corn cause it says clearly on page #9 that the stove is approved to burn wood pellets OR a combination of corn and wood pellets ONLY. Any other fuel will void the warrantee. The manual I have is for my stove which is 6 years old.
Ron
 
Harmans dont like corn
 
Harmans dont like corn
Mine does, guess that is why there will never be a Harman in this home. I might add that 15% RM on corn is really pushing it.

4 grand for a unit that don't like corn... Terrible.... :eek:
 
So they definitely approved corn for P series at least as far back early 2014, as others have indicated. This video from Harman actually states up to 50% corn. So maybe they realized corn isn't that great from too many warranty claims or something, and they forgot to update their "quick notes" in the hopper lid. Wonder how easy getting an answer from them would be. Their customer service seems to be quite lacking.
 
Mine does, guess that is why there will never be a Harman in this home. I might add that 15% RM on corn is really pushing it.

4 grand for a unit that don't like corn... Terrible.... :eek:
what is 15% RM? Also, what is BTU output on corn compared to a decent pellet? And with corn, do you typically only run into trouble with the stove when by products of combustion are allowed to sit in the stove when stove is not in use?
thanks. :)
 
what is 15% RM? Also, what is BTU output on corn compared to a decent pellet? And with corn, do you typically only run into trouble with the stove when by products of combustion are allowed to sit in the stove when stove is not in use?
thanks. :)
15% RM refers to the relative moisture of the corn, measured with a corn specific moisture meter or by weighing an known quantity and comparing it to a chart showing the weight versus relative moisture content.

Far as by products of combustion with corn are concerned, when the kernels carmelize as they combust, the release nitric acid vapor so yes it is deterimental to any stove, especially if you run corn (like I do) and don't follow up with a couple bags of straight pellets with the stove on high to drive off the condensed vapor from the metal surfaces, especially in the fire box which will corrode. nitric is a corrosive to steel.

My unit sits idle all summer but the last good run is with 100% pellets, always, before it gets shut down and cleaned for the summer and I also fog the interior of the firebox with Stabil fogging oil, just to be safe.

Would be foolish for me not to burn corn as it's free for me.
 
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15% RM refers to the relative moisture of the corn, measured with a corn specific moisture meter or by weighing an known quantity and comparing it to a chart showing the weight versus relative moisture content.

Far as by products of combustion with corn are concerned, when the kernels carmelize as they combust, the release nitric acid vapor so yes it is deterimental to any stove, especially if you run corn (like I do) and don't follow up with a couple bags of straight pellets with the stove on high to drive off the condensed vapor from the metal surfaces, especially in the fire box which will corrode. nitric is a corrosive to steel.

My unit sits idle all summer but the last good run is with 100% pellets, always, before it gets shut down and cleaned for the summer and I also fog the interior of the firebox with Stabil fogging oil, just to be safe.

Would be foolish for me not to burn corn as it's free for me.
I have always read that the sugar in corn[ or carmelization] can mess up the stoves inards if not some attention paid to like your burning pellets after the corn...nothing in Harman manual about maintaining the stove if using corn.. 50=50 or whatever.
 
The only inherent drawback about roasting field corn (15%RM or less) is it makes hard clinkers instead of ash like pellets do and it's the hard clinkers that cause grief. When the corn combusts, the shells of the kernels don't burn, they 'melt' for lack of a better description and form the clinkers.

Firepot Pete custom built his corn burn pots (which are much deper than the stock burn pots and uses what he calls a 'clinker hanger' which is a length of wire laying in the burn pot that the clinker envelops and then he removes it but scrapes off the burning material on top into the cleaned pot and continues on.

I use the stock pots (have 2) and by mixing pellets with the corn, it mitigates the clinkers a lot but I still get them so I switch out pots every few days, dump the pot in the stove and replace it with the other pot which has been soaking in a bucket of water. Water loosens the hard carbon on the pot which accumulates from the burning pellets. Quick scrape with a putty knife removes it.

In as much as I don't own a Harmon I cannot say one way or another about burning corn in one or how hard clinkers would impact it.

Not a lot of units out there than can run 100% field corn, mine can even though I don't. 20 years ago about every unit produced was corn capable, not true today.
 
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I got my stove in January of '19 as a leftover from the previous year, and the manual says 50% corn. I don't have a good place to buy shelled corn, or transport it, or store it, so pellets work fine for me.

Prior to EPA Phase III crap, I was looking at a corn/coal/wood boiler, and thought the flexibility would be awesome, but they don't exist anymore.
 
Coal stoves do and if rice coal was readily available here (it's not), I'd be running a Keystoker in a minute. problem with wood stoves today is the catalytic combustor and the need for replacement and I don't do wood, though I have plenty of timber on the property. My buddy in Bar Harbor, Maine heats his house 100% with wood. Has a wood fired boiler in the basement with hydronic baseboard heat. He spends his summers cutting, splitting and stacking wood in his basement for the winter. Not for me. He had a Harmon in his previous home in northern Maine, not sure which one but he always liked it. His present home came with the boiler so that is what he uses. Rice coal is available here but the cost is prohibitive compared to pellets and especially high compared to my never ending supply of corn.

Last winter I was burning off test corn at the rate of 2 55 pound sacks every 24 hours and at 300 bucks plus per sack (55 pounds each), I have the most expensive to run corn burner anywhere I suspect. The corn I burn cannot be sold commercially to farmers because it germs at less than 95%. If corn is below 95% it's not marketable. Nice and clean too, no earwings, no junk, no dirt, just clean and very dry corn. Most of it tests in the 10-12% RM range. Only downside is, I have to dispose of the sacks. They cannot be reused. They are machine stitched closed and each bag has a lot number and type printed on it so I have to destroy (via burn pile) all of them. I do return all the skids however.

All of it is stored in a climate controlled warehouse so it's all dry and packaged when I get it. I have, in the past gotten it in 2000 pound supersacks but last couple years it's all bagged on skids. Still takes some serious tractor with forks to move it around.
 
Problem is field corn is sort of a regional commodity and you have to get hooked up with a local elevator or a farmer with a spare gravity wagon to burn it and it really needs to be below 15% rm or it won't burn proper, but elevators will dry it down to 15 or less before tanking it in storage because wet corn molds and turns to concrete in a grain bin. There are outfits out there that do nothing but jackhammer moldy corn off bin walls. Soybeans and wheat do the same thing but corn is the worst. Back when I bought field corn from the local cooperative, I'd have them magnetically screen it and blow off the earwings and deliver it to my grain tanks, 600 bushel at a time via an auger truck. Back then it was cheap, Today it's not.