Jammed hopper, wide ash band in pot

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Jan 29, 2021
155
VA, east central
How common is it to have the hopper "log jam" and stop feeding pellets? This morning, on startup, I had the hopper jam at the throat and stop dropping pellets with a 3/4 full hopper. This is only my 3rd startup with the Harman P68 and first time I've seen this.
I'm burning Pennington's "Nature's Heat" Pellets and most of the pellets are under an inch long. There are some that might be up to 1.25" though.

Also, I'm running the stove for max temp in "stove temp" mode with a feed rate of 5 right now. I have an inch of bare metal at the burn pot, my understanding is that feed rate should be adjusted so it's an inch of ash at the lip when at max burn. I may have to increase feed rate close to 6 to achieve this. What is the cause of the ash band at the lip of the burn pot to be really wide?
Thanks!
 
Don’t worry about the inch of ash at the end of the burnpot, my P61A never gets there even on high. When it’s cold out...-20f I’m at 4 and 4 on room temp(with probe). As for the “jam”, it’s most likely a one off, but if it keeps happening, empty the hopper and check that the slide is moving properly in test mode.
 
Don’t worry about the inch of ash at the end of the burnpot, my P61A never gets there even on high. When it’s cold out...-20f I’m at 4 and 4 on room temp(with probe). As for the “jam”, it’s most likely a one off, but if it keeps happening, empty the hopper and check that the slide is moving properly in test mode.
Can you see the slide moving from the hopper? I didn't realize that, I was thinking the pellets just flowed through the opening on the one side of that shallow, squarish "shaft" at the bottom of the hopper. But after thinking about it, that would be awful small for pellets to just flow through.
 
Yeah you can see it moving, I have seen a few issues posted here but never had any myself
 
How common is it to have the hopper "log jam" and stop feeding pellets? This morning, on startup, I had the hopper jam at the throat and stop dropping pellets with a 3/4 full hopper. This is only my 3rd startup with the Harman P68 and first time I've seen this.
I'm burning Pennington's "Nature's Heat" Pellets and most of the pellets are under an inch long. There are some that might be up to 1.25" though.

Also, I'm running the stove for max temp in "stove temp" mode with a feed rate of 5 right now. I have an inch of bare metal at the burn pot, my understanding is that feed rate should be adjusted so it's an inch of ash at the lip when at max burn. I may have to increase feed rate close to 6 to achieve this. What is the cause of the ash band at the lip of the burn pot to be really wide?
Thanks!
Awfully high feed rate there.. P61A and never near the edge regardless of what the manual sez.. most Harman P owners are at feed rate 3-4.. i burn good softies at #3 to 3/half and heating 2 floors fine. I will say though that the harmy will feed what it needs to get to temp you have it set for in room auto but u have it on stove mode so depending on the temp your set for it will constand feed to satisfy the ESP probe.. stove mode will burn thru your stash faster than room auto or room manual. At feed rate 5-6 keep a spare bag near the stove as u will need it soon enough...
 
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Awfully high feed rate there.. P61A and never near the edge regardless of what the manual sez.. most Harman P owners are at feed rate 3-4.. i burn good softies at #3 to 3/half and heating 2 floors fine. I will say though that the harmy will feed what it needs to get to temp you have it set for in room auto but u have it on stove mode so depending on the temp your set for it will constand feed to satisfy the ESP probe.. stove mode will burn thru your stash faster than room auto or room manual. At feed rate 5-6 keep a spare bag near the stove as u will need it soon enough...
Interesting. In the latest operator's manual, section 4C, it states the feed rate is set to 4 from the factory and should be adequate for most fuels, then in 4E it states that feed rate of 4 is "conservative" and may need to be increased.

After running the stove for several hours, just barely touching 5 seems to be right for this pellet. As far as using too much fuel, what can I say, it's not pushing unburnt pellets into the ash pan. So maybe calibration between auger RPMs and dial setting is a bit off on my stove?

Either way, I have some experimenting to do yet. I only have around 9.5 hours on it. 1.5 hrs outside to cure paint, then yet another 8 hours hooked up in the basement with the outside door open and fans going b/c odor was still pretty bad. It's still off gassing although I think most of the paint on the stove is done. Of the 8 hours running today, 3-4 was with it cranked to the max. Seems like the stupid durablack 3" to 6" stove pipe adapter that's painted black is still stinking. How, I don't know...
 
With those Penningtons, you probably do need a higher feed rate. When/if you change to a better pellet, you may need to reduce it to 3 or 4.

A couple of years ago I had a short series of jams in my P61a. I don't specifically know why it jammed, but I took a broom handle and swirled up the bottom of the hopper (the first time I had just filled the hopper and extension so didn't want to unload the 100+ pounds).

I think all told it happened 3 times in a short span of time, within the same week certainly. I have burned some long pellets so would guess that whatever I was burning at the time, some long ones started a bridge and that eventually kept anything from passing thru.
 
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Ya know, just re-read the OP post and yes. Burning those cheap pellets would require the higher feed rate of 5 or 6 u started with to get decent heat if possible.. better grade of stock would allow you to lower it..
 
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I don't burn stove mode too much in my Harman p 61 a. Does like to eat pellets but that said, I burn good softwoods like firs, Spruce Woods Etc and since they burn so hot I can lower my feed rate to just below 3 and still get good heat thruout the house and pellets last longer. Mainly i take advantage of the harman tech and run room auto most times. Feed 3-4. As a disclaimer i would not advice lower feed rates unless u have the stock to back it up. Back in the day I burned Box Store pellets on low feed rate and found out it wasn't worth it as the Heat was not there but the ash sure as hell was! Burning 24/7 would come down in the morning and Ash wood be smothering the flame. Look like a candle in the middle of a birthday cake
 
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That's good to know. They were only two bucks a bag, so that's hard to beat. Overnight with feed rate set on 5, constant room temp, and heat setting of 3, I went through pretty much a full bag! That was just 5 hours! :eek:

$2 a bag - you can certainly burn at a higher feed rate, go thru more pellets, and still come out ahead.
 
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I don't burn stove mode too much in my Harman p 61 a. Does like to eat pellets but that said, I burn good softwoods like firs, Spruce Woods Etc and since they burn so hot I can lower my feed rate to just below 3 and still get good heat thruout the house and pellets last longer. Mainly i take advantage of the harman tech and run room auto most times. Feed 3-4. As a disclaimer i would not advice lower feed rates unless u have the stock to back it up. Back in the day I burned Box Store pellets on low feed rate and found out it wasn't worth it as the Heat was not there but the ash sure as hell was! Burning 24/7 would come down in the morning and Ash wood be smothering the flame. Look like a candle in the middle of a birthday cake
So here's the thing though. As the "How your Harman works" sticky thread points out, the feed rate setting is actually the maximum allowable feed rate. So if we were talking about the stove being an automobile, the feed limit knob would control how far you could press your accelerator pedal. If, say 80 was as fast as you car would go, and you set the rate to the half way point and you found you needed to go 60 when you got on the interstate, your max speed would end up being 40. So it's the stove's feed rate limit, or max feed rate setting that comes into play when the exhaust temp indicates more fuel is needed to achieve the stove's constant temp setting as measured by exhaust temp. A lower feed rate limit just lowers the maximum heat output of the stove.

Given that, it seems that adjusting your feed rate properly to allow maximum heat when called for, and then controlling burn rate (and heat output) by the constant temp stove setting is the way to go. Of course burning higher quality pellets to provide more efficiency (higher heat for a given setting) is advisable too if you can get them and think they're worth the extra cost. That would be like using a higher quality gasoline in your car so you wouldn't need to press the accelerator pedal as far to achieve desired acceleration and speeds. But, if your max rate was set properly instead of artificially low, you could accelerate to the max speed should you want to.

BTW, here's my burn pot after about 12 hours of running constant temp w/ temp setting of 2.5, feed limit set to 4.5 and middle distro fan setting. Seems like a lot of ash, but I have nothing to compare to since I'm new to this and I've only tried two different brands of pellets now. I switched from Pennington to "Power Pellets" by O'Malley in Tappahannock, VA last night. Some glowing pellets are sandwiched into the ash, so that's definitely not good so I'd say too much ash. Not sure if it's the pellet brand or if it could be higher moisture content as these few bags weren't covered properly at the store and had a damp spot I had to discard. But I got the bags for $2/bag!==c

So I really need to experiment and see if constant temp or room temp mode is going to be best for me. And of course, get better pellets!

20210321_094229[1].jpg

20210321_102025[1].jpg
 
So here's the thing though. As the "How your Harman works" sticky thread points out, the feed rate setting is actually the maximum allowable feed rate. So if we were talking about the stove being an automobile, the feed limit knob would control how far you could press your accelerator pedal. If, say 80 was as fast as you car would go, and you set the rate to the half way point and you found you needed to go 60 when you got on the interstate, your max speed would end up being 40. So it's the stove's feed rate limit, or max feed rate setting that comes into play when the exhaust temp indicates more fuel is needed to achieve the stove's constant temp setting as measured by exhaust temp. A lower feed rate limit just lowers the maximum heat output of the stove.

Given that, it seems that adjusting your feed rate properly to allow maximum heat when called for, and then controlling burn rate (and heat output) by the constant temp stove setting is the way to go. Of course burning higher quality pellets to provide more efficiency (higher heat for a given setting) is advisable too if you can get them and think they're worth the extra cost. That would be like using a higher quality gasoline in your car so you wouldn't need to press the accelerator pedal as far to achieve desired acceleration and speeds. But, if your max rate was set properly instead of artificially low, you could accelerate to the max speed should you want to.

BTW, here's my burn pot after about 12 hours of running constant temp w/ temp setting of 2.5, feed limit set to 4.5 and middle distro fan setting. Seems like a lot of ash, but I have nothing to compare to since I'm new to this and I've only tried two different brands of pellets now. I switched from Pennington to "Power Pellets" by O'Malley in Tappahannock, VA last night. Some glowing pellets are sandwiched into the ash, so that's definitely not good so I'd say too much ash. Not sure if it's the pellet brand or if it could be higher moisture content as these few bags weren't covered properly at the store and had a damp spot I had to discard. But I got the bags for $2/bag!==c

So I really need to experiment and see if constant temp or room temp mode is going to be best for me. And of course, get better pellets!

View attachment 276919
View attachment 276920
good read...
the O'malley's are a very ashy pellet as i have used them in the past so u won't get much better with them.
 
So here's the thing though. As the "How your Harman works" sticky thread points out, the feed rate setting is actually the maximum allowable feed rate. So if we were talking about the stove being an automobile, the feed limit knob would control how far you could press your accelerator pedal. If, say 80 was as fast as you car would go, and you set the rate to the half way point and you found you needed to go 60 when you got on the interstate, your max speed would end up being 40. So it's the stove's feed rate limit, or max feed rate setting that comes into play when the exhaust temp indicates more fuel is needed to achieve the stove's constant temp setting as measured by exhaust temp. A lower feed rate limit just lowers the maximum heat output of the stove.

Given that, it seems that adjusting your feed rate properly to allow maximum heat when called for, and then controlling burn rate (and heat output) by the constant temp stove setting is the way to go. Of course burning higher quality pellets to provide more efficiency (higher heat for a given setting) is advisable too if you can get them and think they're worth the extra cost. That would be like using a higher quality gasoline in your car so you wouldn't need to press the accelerator pedal as far to achieve desired acceleration and speeds. But, if your max rate was set properly instead of artificially low, you could accelerate to the max speed should you want to.

BTW, here's my burn pot after about 12 hours of running constant temp w/ temp setting of 2.5, feed limit set to 4.5 and middle distro fan setting. Seems like a lot of ash, but I have nothing to compare to since I'm new to this and I've only tried two different brands of pellets now. I switched from Pennington to "Power Pellets" by O'Malley in Tappahannock, VA last night. Some glowing pellets are sandwiched into the ash, so that's definitely not good so I'd say too much ash. Not sure if it's the pellet brand or if it could be higher moisture content as these few bags weren't covered properly at the store and had a damp spot I had to discard. But I got the bags for $2/bag!==c

So I really need to experiment and see if constant temp or room temp mode is going to be best for me. And of course, get better pellets!

View attachment 276919
View attachment 276920
Looks like the breaded fish patties my wife made for dinner last night.............. :p
 
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good read...
the O'malley's are a very ashy pellet as i have used them in the past so u won't get much better with them.
Doesn't O'malley's have several plants, pretty sure they do. I've seen a few reviews online, some people seem to like them, some don't. I seem to remember it varying by location. Or they make lower quality pellets at all their locations. :D
I need to search around and see what can be had here south of D.C. in VA. With lowes, etc. suppliers seems to vary throughout the season from what I've paid attention to in the last two months.
 
lol, well they were kinda crusty. I guess wanna be clinkers, it crumbled fairly easily.
The ton i burned here "north of you " outside philly left the hardest speedbumps known to man in my burnpot.. talking hammer/chisel time.. few yrs ago i will say..could not wait till the ton was gone...
 
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Couple things to consider...

1. Pellets can vary from bag to bag or skid to skid, depending on how old they are and where and how they were stored.

2. Just because they are stamped 'premium' or have the PFI certification means nothing. Pellets are entirely dependent on the feedstock the extruder is using at that time. Consequently, if the pellet plant is using forestry slash, the product will be of one quality but if they use recycled pallets for feedstock, the quality of the end product will change and the feedstock can change many times throughout the year, consequently, the burn quality changes with the input feedstock.

Why I like burning corn. Midwestern Dent field corn is extremely consistent in not only kernel size but density as well. It's all been genetically uniformed over the years so burn quality never varies, plus there is no dust or fines like with pellets.

Why I always like roasting Somerset pellets. Somerset Hardwood flooring only uses their hardwood flooring scraps from their mill in Somerset Kentucky for feedstock. Consequently, their pellets are as about as consistent in quality as you can get but. even they can vary a bit, depending on what forestry lot they are using at the time.

Other than Somerset, I haven't a clue where the rest source their feedstock from but I do know that the quality of them changes with the feedstock they use.
 
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