Harman distribution air temp differences between pellets?

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mepellet

Minister of Fire
Aug 10, 2011
2,139
Central ME
I read about people getting more heat from different pellets. Even people with Harmans like mine. I don’t understand how people with Harmans get noticeable temperature differences between pellets especially in stove temp mode. I thought in stove temp mode that the exhaust probe controls the stove temperature. From my understanding, if the stove temp mode is really trying to maintain a certain exhaust temperature and the probe senses a lower temperature, it tells the computer to tell the auger to start feeding pellets. Therefore, relatively speaking, the distribution air temp should be approximately the same temp from pellet to pellet right? What am I missing?
 
mepellet said:
I read about people getting more heat from different pellets. Even people with Harmans like mine. I don’t understand how people with Harmans get noticeable temperature differences between pellets especially in stove temp mode. I thought in stove temp mode that the exhaust probe controls the stove temperature. From my understanding, if the stove temp mode is really trying to maintain a certain exhaust temperature and the probe senses a lower temperature, it tells the computer to tell the auger to start feeding pellets. Therefore, relatively speaking, the distribution air temp should be approximately the same temp from pellet to pellet right? What am I missing?
Try this. Set your stove temp to any setting you want. Then set your feed rate to any setting you want. Clean your stove and run a bag of those Maine Woods or Green Supremes through the stove and put your hand up to the convection air coming out. Then, clean your stove again, and on the SAME SETTINGS, run a bag of Okies, Barefoot, or Cubex (all 3 should be in your area) through the stove. Put your hand up to the convection air coming out and feel that. You WILL notice a difference. If not, I agree right here and now to change my avatar and let you pick the next one. AIN'T GUNNA HAPPEN! There is a huge difference between these pellets I name and the ones in your sig. Trust me!
 
Using his test, you may also have to take in account the size of the pellets. With my auger, the smaller the pellet the more volume of fuel is fed to the burn pot per auger cycle. This raises the temp on mine but burns a bag quicker.
I'm burnning firesides from HD (~$3.60) a bag and only burn a bag a day on low.
My stove does better with hardwood, and I've found some batches are hotter then others.
 
A hotter pellet will also allow the stove to get to that temp a lot faster. Thereby saving pellets.

(P.S.- Thanks again)
 
mepellet said:
I read about people getting more heat from different pellets. Even people with Harmans like mine. I don’t understand how people with Harmans get noticeable temperature differences between pellets especially in stove temp mode. I thought in stove temp mode that the exhaust probe controls the stove temperature. From my understanding, if the stove temp mode is really trying to maintain a certain exhaust temperature and the probe senses a lower temperature, it tells the computer to tell the auger to start feeding pellets. Therefore, relatively speaking, the distribution air temp should be approximately the same temp from pellet to pellet right? What am I missing?

You are correct. You won't see any temperature differences (more than a few %), but you WILL see a CONSUMPTION difference. ESP probe drives temp, so a hotter pellet will slow down the feed rate to meet ESP temp. Slower feed rate = burning less pellets.

For example, if you set the stove temp setting to maintain a 300 degree ESP temp, then the best pellet or worst pellet will produce very close to the same air temps out of the stove because the ESP is feeding more (cold pellet) or feeding less (hot pellet) to maintain the 300 degree setting. We won't feel the difference, but we might get 24 hours out of the hot pellet and 20 hours out of the cold pellet.

Other stoves are based on fixed rates, so hotter pellets WILL produce hotter convection temps.

Johnny, shall we start looking for another avatar?
 
johnnycomelately said:
mepellet said:
I read about people getting more heat from different pellets. Even people with Harmans like mine. I don’t understand how people with Harmans get noticeable temperature differences between pellets especially in stove temp mode. I thought in stove temp mode that the exhaust probe controls the stove temperature. From my understanding, if the stove temp mode is really trying to maintain a certain exhaust temperature and the probe senses a lower temperature, it tells the computer to tell the auger to start feeding pellets. Therefore, relatively speaking, the distribution air temp should be approximately the same temp from pellet to pellet right? What am I missing?
Try this. Set your stove temp to any setting you want. Then set your feed rate to any setting you want. Clean your stove and run a bag of those Maine Woods or Green Supremes through the stove and put your hand up to the convection air coming out. Then, clean your stove again, and on the SAME SETTINGS, run a bag of Okies, Barefoot, or Cubex (all 3 should be in your area) through the stove. Put your hand up to the convection air coming out and feel that. You WILL notice a difference. If not, I agree right here and now to change my avatar and let you pick the next one. AIN'T GUNNA HAPPEN! There is a huge difference between these pellets I name and the ones in your sig. Trust me!

I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.
 
DexterDay said:
A hotter pellet will also allow the stove to get to that temp a lot faster. Thereby saving pellets.

(P.S.- Thanks again)

My pleasure! Anytime.
I understand what you are saying but once it gets to that temp, isn't the distribution air temp going to remain close to the same from pellet to pellet?
 
lbcynya said:
mepellet said:
I read about people getting more heat from different pellets. Even people with Harmans like mine. I don’t understand how people with Harmans get noticeable temperature differences between pellets especially in stove temp mode. I thought in stove temp mode that the exhaust probe controls the stove temperature. From my understanding, if the stove temp mode is really trying to maintain a certain exhaust temperature and the probe senses a lower temperature, it tells the computer to tell the auger to start feeding pellets. Therefore, relatively speaking, the distribution air temp should be approximately the same temp from pellet to pellet right? What am I missing?

You are correct. You won't see any temperature differences (more than a few %), but you WILL see a CONSUMPTION difference. ESP probe drives temp, so a hotter pellet will slow down the feed rate to meet ESP temp. Slower feed rate = burning less pellets.

For example, if you set the stove temp setting to maintain a 300 degree ESP temp, then the best pellet or worst pellet will produce very close to the same air temps out of the stove because the ESP is feeding more (cold pellet) or feeding less (hot pellet) to maintain the 300 degree setting. We won't feel the difference, but we might get 24 hours out of the hot pellet and 20 hours out of the cold pellet.

Other stoves are based on fixed rates, so hotter pellets WILL produce hotter convection temps.

Johnny, shall we start looking for another avatar?

ah hah! So am I correct? I knew the hotter (higher BTU) pellets woud last longer in stove temp. Just couldn't see how they would create a different distribution air temperature. Guess I may not have been missing anything...

I think we need more responses saying that Johnny is wrong before we start looking for another avatar.
 
mepellet said:
I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.
Explanation:
Some pellets burn hotter than others.

For you to run the experiment that I have proposed, will cost you an initial investment of $5-$6. I feel the heat difference for sure, and that's saying something, as sometimes I can't even feel the sensation that tells me that I have to pee.
 
mepellet said:
I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.

It's been proven, just look at the pellet tests that have been done on here and the temp differences between them. Even between "super premium" brands there is temperature variation.
 
johnnycomelately said:
mepellet said:
I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.
Explanation:
Some pellets burn hotter than others.

For you to run the experiment that I have proposed, will cost you an initial investment of $5-$6. I feel the heat difference for sure, and that's saying something, as sometimes I can't even feel the sensation that tells me that I have to pee.

I understand that some pellets burn hotter than others but that doesn't really answer my question. Do you have a harman P series stove?
 
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you
 
76brian said:
mepellet said:
I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.

It's been proven, just look at the pellet tests that have been done on here and the temp differences between them. Even between "super premium" brands there is temperature variation.

I believe those tests have not been done on a Harman stove. Again, I understand that different pellets have different BTU content. I am curious if the control board compensates for this in stove mode to produce a certain exhaust temperature therefor regulating the distribution air temperature.
 
mepellet said:
76brian said:
mepellet said:
I don't trust you! haha. If what you say is true, explain the reason for it. I just don't understand.

It's been proven, just look at the pellet tests that have been done on here and the temp differences between them. Even between "super premium" brands there is temperature variation.

I believe those tests have not been done on a Harman stove. Again, I understand that different pellets have different BTU content. I am curious if the control board compensates for this in stove mode to produce a certain exhaust temperature therefor regulating the distribution air temperature.
YOU'RE RIGHT!!!...There is no differene between the brands as far as heat goes.
 
ironpony said:
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you

Based on hours of watching my Harman diagnostic tool, your post is half right. Stove temp sets a TARGET temp, not a minimum temp. The feed rate WILL fluctuate to maintain target temp. So a hotter pellet will result in a lower feed rate to maintain the target temp. The ESP will allow about a 20-30 degree delta from target to high/low. So a target temp of 300 will see ESP temps or around 285 to 315. BTU content of pellet doesn't matter, stove only adjusts based on ESP temp, not BTU.

Now, back to the new avatar... :)
 
lbcynya said:
ironpony said:
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you

Based on hours of watching my Harman diagnostic tool, your post is half right. Stove temp sets a TARGET temp, not a minimum temp. The feed rate WILL fluctuate to maintain target temp. So a hotter pellet will result in a lower feed rate to maintain the target temp. The ESP will allow about a 20-30 degree delta from target to high/low. So a target temp of 300 will see ESP temps or around 285 to 315. BTU content of pellet doesn't matter, stove only adjusts based on ESP temp, not BTU.

Now, back to the new avatar... :)

and if it feeds one rotation of HOTTER burnig pellets and the ESP see's 450 degrees
does it spray water on them to cool them down
no, they burn down to the low end and it stars over again

keep the avatar Johny
 
Are you fella's talking about my testing/reviews? If so, No they were done with an Enviro Omega stove.

Interesting if the Harman can comp for the fuel. I'd love to see what some of them like Barefoot or Hamers would do in them compared to say Stove Chow. Heat vs length of burn. If the pellets that tested cooler in mine were adjusted to bring the temp up. i bet they wouldnt last as long as the hotter stuff.
 
ironpony said:
lbcynya said:
ironpony said:
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you

Based on hours of watching my Harman diagnostic tool, your post is half right. Stove temp sets a TARGET temp, not a minimum temp. The feed rate WILL fluctuate to maintain target temp. So a hotter pellet will result in a lower feed rate to maintain the target temp. The ESP will allow about a 20-30 degree delta from target to high/low. So a target temp of 300 will see ESP temps or around 285 to 315. BTU content of pellet doesn't matter, stove only adjusts based on ESP temp, not BTU.

Now, back to the new avatar... :)

and if it feeds one rotation of HOTTER burnig pellets and the ESP see's 450 degrees
does it spray water on them to cool them down
no, they burn down to the low end and it stars over again

keep the avatar Johny

My facts vs. you shooting from the hip... I'll let the reader choose who they want to believe. Sorry, 1 auger rotation is barely enough to increase temps more than a handful or two of degrees... Temps will overshoot as I noted, but not by 150 degrees. Geez... We're talking wood here, not dynamite. 8,000 vs 9,000 BTU pellet is based on weight and a single rotation only drops a few ounces, not pounds. That's a 12% increase in overall BTU.

Unless you can come up with hard facts/data vs. your hypothesis, Johnny's avatar is toast.
 
lbcynya said:
ironpony said:
lbcynya said:
ironpony said:
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you

Based on hours of watching my Harman diagnostic tool, your post is half right. Stove temp sets a TARGET temp, not a minimum temp. The feed rate WILL fluctuate to maintain target temp. So a hotter pellet will result in a lower feed rate to maintain the target temp. The ESP will allow about a 20-30 degree delta from target to high/low. So a target temp of 300 will see ESP temps or around 285 to 315. BTU content of pellet doesn't matter, stove only adjusts based on ESP temp, not BTU.

Now, back to the new avatar... :)

and if it feeds one rotation of HOTTER burnig pellets and the ESP see's 450 degrees
does it spray water on them to cool them down
no, they burn down to the low end and it stars over again

keep the avatar Johny

My facts vs. you shooting from the hip... I'll let the reader choose who they want to believe. Sorry, 1 auger rotation is barely enough to increase temps more than a handful or two of degrees... Temps will overshoot as I noted, but not by 150 degrees. Geez... We're talking wood here, not dynamite. 8,000 vs 9,000 BTU pellet is based on weight and a single rotation only drops a few ounces, not pounds. That's a 12% increase in overall BTU.

Unless you can come up with hard facts/data vs. your hypothesis, Johnny's avatar is toast.


lbcynya is absolutely correct on this one for Harman stoves. mepellet asked about Harman distribution air temps from different pellets. This is how the Harman operates. Some stoves operate one way and other stoves operate their own way. And this question was asked about Harman stoves so if someone doesn't have a Harman and doesn't know how it operates it looks odd when that same person posts a comment. In other words if you don't know what you are talking about maybe you shouldn't add a comment. :)
 
PJPellet said:
lbcynya is absolutely correct on this one for Harman stoves. mepellet asked about Harman distribution air temps from different pellets. This is how the Harman operates. Some stoves operate one way and other stoves operate their own way. And this question was asked about Harman stoves so if someone doesn't have a Harman and doesn't know how it operates it looks odd when that same person posts a comment. In other words if you don't know what you are talking about maybe you shouldn't add a comment. :)

Not to add fuel to the fire so to speak, but when my house is cold, and the weather outside being equal, it gets up to temp a lot quicker with Cubex or LG than it does with the other brands I have tried. Not very scientific, I know, but it's an observation. I don't have a way to measure the air coming out of the stove, but I do have one of those magnetic thermometers on the side of the stove that seems to go higher with good pellets than it does with others.

I normally use room temp though, not stove temp, but this observation of mine, plus the measurements of output on other stoves proves to me that there is most definitely a difference.
 
76brian said:
PJPellet said:
lbcynya is absolutely correct on this one for Harman stoves. mepellet asked about Harman distribution air temps from different pellets. This is how the Harman operates. Some stoves operate one way and other stoves operate their own way. And this question was asked about Harman stoves so if someone doesn't have a Harman and doesn't know how it operates it looks odd when that same person posts a comment. In other words if you don't know what you are talking about maybe you shouldn't add a comment. :)

Not to add fuel to the fire so to speak, but when my house is cold, and the weather outside being equal, it gets up to temp a lot quicker with Cubex or LG than it does with the other brands I have tried. Not very scientific, I know, but it's an observation. I don't have a way to measure the air coming out of the stove, but I do have one of those magnetic thermometers on the side of the stove that seems to go higher with good pellets than it does with others.

I normally use room temp though, not stove temp.

I think you answered this one yourself. Room temp vs. stove temp. But what do I know? ;)
 
PJPellet said:
lbcynya said:
ironpony said:
lbcynya said:
ironpony said:
O.K. here is the answer................................................
the ESP see's minimun temp to maintain
so when the pellets drop and burn HOTTER they put out more HEAT
until the temp drops enough to call for more pellets
which enter the burn pot and burn HOTTER
till the temp drops to minimun and repeat

you get to keep that ugly avatar
thank you

Based on hours of watching my Harman diagnostic tool, your post is half right. Stove temp sets a TARGET temp, not a minimum temp. The feed rate WILL fluctuate to maintain target temp. So a hotter pellet will result in a lower feed rate to maintain the target temp. The ESP will allow about a 20-30 degree delta from target to high/low. So a target temp of 300 will see ESP temps or around 285 to 315. BTU content of pellet doesn't matter, stove only adjusts based on ESP temp, not BTU.

Now, back to the new avatar... :)

and if it feeds one rotation of HOTTER burnig pellets and the ESP see's 450 degrees
does it spray water on them to cool them down
no, they burn down to the low end and it stars over again

keep the avatar Johny

My facts vs. you shooting from the hip... I'll let the reader choose who they want to believe. Sorry, 1 auger rotation is barely enough to increase temps more than a handful or two of degrees... Temps will overshoot as I noted, but not by 150 degrees. Geez... We're talking wood here, not dynamite. 8,000 vs 9,000 BTU pellet is based on weight and a single rotation only drops a few ounces, not pounds. That's a 12% increase in overall BTU.

Unless you can come up with hard facts/data vs. your hypothesis, Johnny's avatar is toast.


lbcynya is absolutely correct on this one for Harman stoves. mepellet asked about Harman distribution air temps from different pellets. This is how the Harman operates. Some stoves operate one way and other stoves operate their own way. And this question was asked about Harman stoves so if someone doesn't have a Harman and doesn't know how it operates it looks odd when that same person posts a comment. In other words if you don't know what you are talking about maybe you shouldn't add a comment. :)

PJPellet & lbcynya,
Any suggestions for Johnny's new avatar?
 
76brian said:
PJPellet said:
lbcynya is absolutely correct on this one for Harman stoves. mepellet asked about Harman distribution air temps from different pellets. This is how the Harman operates. Some stoves operate one way and other stoves operate their own way. And this question was asked about Harman stoves so if someone doesn't have a Harman and doesn't know how it operates it looks odd when that same person posts a comment. In other words if you don't know what you are talking about maybe you shouldn't add a comment. :)

Not to add fuel to the fire so to speak, but when my house is cold, and the weather outside being equal, it gets up to temp a lot quicker with Cubex or LG than it does with the other brands I have tried. Not very scientific, I know, but it's an observation. I don't have a way to measure the air coming out of the stove, but I do have one of those magnetic thermometers on the side of the stove that seems to go higher with good pellets than it does with others.

I normally use room temp though, not stove temp.

Correct as well! With a HARMAN (I can only speak for Harman) a call for heat in Room Temp will result in a max feed (based on knob setting) and max ESP temp target (500 degrees for most). So, a hotter pellet will ramp up faster than a cold pellet. Some colder pellets might not even make it to the 500 degree target before the call for heat is satisfied.

Just to insure we're not missing something here - I'm not suggesting that anyone buy a cold pellet. Always buy the hottest pellet if the price is reasonable. The goal is to make heat and save money...bottom line.
 
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