Wood pellets...pellet size matters

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j-takeman said:
1Dtml said:
I've been following this thread, and it inspired me to do a bit of on hand research.
I've been burning Somersets in my Enviro Maxx, and the size of pellet is pretty consistent on the smallish side.
To my knowledge Somersets are all hardwood, so this is what I presume for this experiment.
My temperature readings have been from 280*F to over 300*F, but the most consistent reading I get is 289*F with the flame optimized and the stove running for over an hour. When optimized I get very little ash, and very little build up on the burn pot.
After a stove cleaning I went to MWP for the first time, and noticed that these pellets are consistently smaller than the Somerset pellets, so these should burn hotter according to this thread.
For the first run I left the stove adjusted the same as for the Somerset pellets, and the temperatures were 230*F- 250*F with the most consistent temp being 240*F.
I could tell from the flame that it had too much air for this pellet, but I continued the experiment because I noticed a bunch more ash, and carbon build up.
I gave the stove a cleaning to proceed with my experiment.
I then ran the MWP pellets with the flame optimized to find that the temps ran from 250*F to 280*F with the most consistent reading being 263*F.
I was more amazed that the ash amount with the flame optimized was much less, and very little burn pot build up with the glass staying cleaner than with the Somerset pellets burning at optimum.
It appears that ash build up has more to do with an optimized burn than the quality of the pellet.

Some have mentioned pellet density being a factor in heat production, and I believe my experiment may give this theory a boost.

I have also noticed that there is a hardwood vs softwood heat production argument going on with many threads, but after my experiment I think that hardwood/softwood blends in general may be the pellet that produces less heat, any thought on this???

The MWP is a hardwood/softwood blend, and I have run many other blends from other manufactures, and all have produced less heat than any of my straight hardwood or softwood pellets, but I will definitely be tuning each of my stoves for optimal burning from now on, for more heat and less cleaning sounds good to me.

1D

OK the variables got you!

1st. is density, Although the MWP pellets are smaller. They are not as dense as the Somersets. The more fuel in is greater with a dense pellet. You can prove this with a common scale. Fill a jar or box with Somersets. Settle it slightly. Then weigh it and note the weight. Do the same with the MWP and compare. The heavier weight should be Somersets because of the higher density.

2nd. Is fiber of the wood species. Seeing the Somerset is mostly oak fiber. You see more heat even if they were about the same size/density. Although minimal it is a factor. Many don't believe that, But I do. Just hard to prove without a lab and special equipment.





as long as the density is fiber not filler taht some use
so a heavier pellet could put out less heat
another variable
the way I see it, even not so good pellets are cheaper than oil, electric or propane
or just buy a HarmAn
all pellets burn the same
 
j-takeman said:
1Dtml said:
I've been following this thread, and it inspired me to do a bit of on hand research.
I've been burning Somersets in my Enviro Maxx, and the size of pellet is pretty consistent on the smallish side.
To my knowledge Somersets are all hardwood, so this is what I presume for this experiment.
My temperature readings have been from 280*F to over 300*F, but the most consistent reading I get is 289*F with the flame optimized and the stove running for over an hour. When optimized I get very little ash, and very little build up on the burn pot.
After a stove cleaning I went to MWP for the first time, and noticed that these pellets are consistently smaller than the Somerset pellets, so these should burn hotter according to this thread.
For the first run I left the stove adjusted the same as for the Somerset pellets, and the temperatures were 230*F- 250*F with the most consistent temp being 240*F.
I could tell from the flame that it had too much air for this pellet, but I continued the experiment because I noticed a bunch more ash, and carbon build up.
I gave the stove a cleaning to proceed with my experiment.
I then ran the MWP pellets with the flame optimized to find that the temps ran from 250*F to 280*F with the most consistent reading being 263*F.
I was more amazed that the ash amount with the flame optimized was much less, and very little burn pot build up with the glass staying cleaner than with the Somerset pellets burning at optimum.
It appears that ash build up has more to do with an optimized burn than the quality of the pellet.

Some have mentioned pellet density being a factor in heat production, and I believe my experiment may give this theory a boost.

I have also noticed that there is a hardwood vs softwood heat production argument going on with many threads, but after my experiment I think that hardwood/softwood blends in general may be the pellet that produces less heat, any thought on this???

The MWP is a hardwood/softwood blend, and I have run many other blends from other manufactures, and all have produced less heat than any of my straight hardwood or softwood pellets, but I will definitely be tuning each of my stoves for optimal burning from now on, for more heat and less cleaning sounds good to me.

1D

OK the variables got you!

1st. is density, Although the MWP pellets are smaller. They are not as dense as the Somersets. The more fuel in is greater with a dense pellet. You can prove this with a common scale. Fill a jar or box with Somersets. Settle it slightly. Then weigh it and note the weight. Do the same with the MWP and compare. The heavier weight should be Somersets because of the higher density.

2nd. Is fiber of the wood species. Seeing the Somerset is mostly oak fiber. You see more heat even if they were about the same size/density. Although minimal it is a factor. Many don't believe that, But I do. Just hard to prove without a lab and special equipment.

Yuph, I mentioned that this gave the density theory a boost, so I agree.
My points were that one should optimize the burn of any given pellet, or I'm sure some will say "buy a Harman." ;-)
This should not only provide your pellet gives out its max heat production, but I think you will have less ash to deal with.
I was also guessing that both 100% hardwood or 100% softwood pellets have a higher density level than most if not all blends??
You have done much testing, so are there any blends that produce the heat levels of the 100% hard or soft pellets???

I think that if a stove is not tuned for the pellet that is being burned that the results will vary greatly, hence why we are always saying "try some for all stoves are different."

I was very surprised at the amount of ash (a bunch) that was produced by the MWP pellets when the burn wasn't optimized when compared to the same MWP pellets producing (very little) ash when the burn was optimized.

I will be optimizing for each pellet brand I use before deciding which to purchase from now on....just sayin! ;-P

1D
 
1Dtml said:
j-takeman said:
1Dtml said:
I've been following this thread, and it inspired me to do a bit of on hand research.
I've been burning Somersets in my Enviro Maxx, and the size of pellet is pretty consistent on the smallish side.
To my knowledge Somersets are all hardwood, so this is what I presume for this experiment.
My temperature readings have been from 280*F to over 300*F, but the most consistent reading I get is 289*F with the flame optimized and the stove running for over an hour. When optimized I get very little ash, and very little build up on the burn pot.
After a stove cleaning I went to MWP for the first time, and noticed that these pellets are consistently smaller than the Somerset pellets, so these should burn hotter according to this thread.
For the first run I left the stove adjusted the same as for the Somerset pellets, and the temperatures were 230*F- 250*F with the most consistent temp being 240*F.
I could tell from the flame that it had too much air for this pellet, but I continued the experiment because I noticed a bunch more ash, and carbon build up.
I gave the stove a cleaning to proceed with my experiment.
I then ran the MWP pellets with the flame optimized to find that the temps ran from 250*F to 280*F with the most consistent reading being 263*F.
I was more amazed that the ash amount with the flame optimized was much less, and very little burn pot build up with the glass staying cleaner than with the Somerset pellets burning at optimum.
It appears that ash build up has more to do with an optimized burn than the quality of the pellet.

Some have mentioned pellet density being a factor in heat production, and I believe my experiment may give this theory a boost.

I have also noticed that there is a hardwood vs softwood heat production argument going on with many threads, but after my experiment I think that hardwood/softwood blends in general may be the pellet that produces less heat, any thought on this???

The MWP is a hardwood/softwood blend, and I have run many other blends from other manufactures, and all have produced less heat than any of my straight hardwood or softwood pellets, but I will definitely be tuning each of my stoves for optimal burning from now on, for more heat and less cleaning sounds good to me.

1D

OK the variables got you!

1st. is density, Although the MWP pellets are smaller. They are not as dense as the Somersets. The more fuel in is greater with a dense pellet. You can prove this with a common scale. Fill a jar or box with Somersets. Settle it slightly. Then weigh it and note the weight. Do the same with the MWP and compare. The heavier weight should be Somersets because of the higher density.

2nd. Is fiber of the wood species. Seeing the Somerset is mostly oak fiber. You see more heat even if they were about the same size/density. Although minimal it is a factor. Many don't believe that, But I do. Just hard to prove without a lab and special equipment.

Yuph, I mentioned that this gave the density theory a boost, so I agree.
My points were that one should optimize the burn of any given pellet, or I'm sure some will say "buy a Harman." ;-)
This should not only provide your pellet gives out its max heat production, but I think you will have less ash to deal with.
I was also guessing that both 100% hardwood or 100% softwood pellets have a higher density level than most if not all blends??
You have done much testing, so are there any blends that produce the heat levels of the 100% hard or soft pellets???

I think that if a stove is not tuned for the pellet that is being burned that the results will vary greatly, hence why we are always saying "try some for all stoves are different."

I was very surprised at the amount of ash (a bunch) that was produced by the MWP pellets when the burn wasn't optimized when compared to the same MWP pellets producing (very little) ash when the burn was optimized.

I will be optimizing for each pellet brand I use before deciding which to purchase from now on....just sayin! ;-P

1D

When you got feed trim and combustion trim on your side. You can tweak the burn. Basically what the harman is doing. Ours isn't automatic, But we can tweak to what we want(not what a computer wants). Yeah fuel injection is easier, But carbs are tinkering man's toys! Usually only needed if pellet brands are changed. And something to do when its cold out. I would rather be tweaking my stove and hugging my pellets than watching the tellie anyway!
 
That's what I'm saying, now that I've got the tweaking down it opens up more options as to pellet brands.

So did you ever find a hard/soft blend that could come close to the 100%s in heat production???

This may be a short cut to knowing what produces more heat without trying every brand out there.

1D
 
1Dtml said:
That's what I'm saying, now that I've got the tweaking down it opens up more options as to pellet brands.

So did you ever find a hard/soft blend that could come close to the 100%s in heat production???

This may be a short cut to knowing what produces more heat without trying every brand out there.

1D

The lignetic's green(with conifer) was about the best in the blends.
 
Results of my totally unscientific test.

Here is one of you tests: https://www.hearth.com/talk/threads/50101/

I just took the averages of temperatures from your tables, and found the following:

100% hardwood pellets average temperature = 245*F

100% softwood pellets average temperature = 247*F

hardwood/softwood blend pellets average temperature = 233*F

Not a large sample, and I'm not sure that you optimized your burn settings, so this may mean nothing, but is interesting none the less.

1D
 
1D said:
Results of my totally unscientific test.

Here is one of you tests: https://www.hearth.com/talk/threads/50101/

I just took the averages of temperatures from your tables, and found the following:

100% hardwood pellets average temperature = 245*F

100% softwood pellets average temperature = 247*F

hardwood/softwood blend pellets average temperature = 233*F

Not a large sample, and I'm not sure that you optimized your burn settings, so this may mean nothing, but is interesting none the less.

1D

To be close in the approx. times of the testing. I set them all to heat setting 3 and feed trim 3. Only adjusted damper air to get a consistent flame. Should be close enough for none lab test result's And many stoves out there don't have feed trim anyways.
 
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