Darn good question. I have no idea what it does differently, but if you figure it out, let me know!

I can tell for sure it is feeding faster as the old auger the hopper would last me about 24 hours on a setting of "2" (this includes me mounding up the pellets every so often when it creates that funnel after several hours). This time, I filled it up and it went about 18-19 hours.

I suspect something may be up with the electronics. Sparta said it was on backorder and I had to wait for them to get it direct from Nesco before they sent it out. It is a full corkscrew on the auger all the way to the end and looks to have the same angle as the original auger. It's on about a setting of 2 right now (because it's cold out, so it's probably equivalent to 4 or 5 with my old auger) and it runs for about 2 seconds and pauses for 4 seconds. I'll have to dig, but I thought the pause period was much longer, hence the higher feed rate right now.

Edit:
Well, 4 second pause seems correct according to the old forums. I know the brass bearing wasn't gummed up as it was clean when I swapped augers and I had cleaned it at the start of the season. It's the only thing I changed during the last cleaning and the pellets are the same. Very strange.

Picture of the two augers for comparison.

Just putting in an update. I patched in a fan controller and slowing down the fan some did increase my heat output (with the added benefit of getting rid of the slight hum the blower would sometimes make at full speed). Examining the IR thermometer, it seems to actually read a little above where the red beam hits, so I believe I finally got it to the point of being about 400F when at a setting of 3. That was all the past week of fiddling.

Today I shut it down for cleaning and found some tools to finally swap out the auger. I have to say, the multifuel auger must feed pellets like crazy, as I fired it up and set it for 2 and checked an hour later. The spot above the door was reading somewhere in the neighborhood of 530F and the flame was much bigger than a setting of 5 with the old auger.

So in conclusion, while I have no idea what the exhaust temps are now, the blower by default seems to possibly have been a little too powerful to get maximum heat (but it might keep the glass cleaner longer). The replacement auger also seems to feed pellets at a much faster pace (maybe a little more than 2x). While no two stoves probably can produce the exact same heat output, I put this here as a reference/data point.

Well, signing out for the night, but here's what my readings seem to be. Interesting thing is even when I tried to close the air screw as much as possible, the flame was still bouncing around really actively, just got smaller and more of it was blue. Think taking a kid and giving them a syringe full of liquid sugar

280 260 230 - Original setting 3/16" (2 1/4 turns)
300 280 250 - Second reading at 2 1/4 turns
340 300 260 - Screw at 1 3/4
280 255 225 - Screw at 1 1/2
290 270 240 - Screw at 2
280 260 220 - Screw at 0
360 320 280 - Screw at 1 3/4, popped baffle mod in

Fan control should be coming in end of the week or sometime next week, so I'll have to try that and let you guys know if that makes the flames act more mature (active, but not hyperactive movement).

tfgrower wrote:


Yup, that's him. He was the one who suggested trying to turn the air screw down more as well, but he also said one could put in some switch, however it would affect the air wash system as well. As you can see above, he said he was going to try that on his own system at home. I should ask him how that turned out, while I'm thinking about it.

Here's a quick view of me re-lighting the pot so command_z can see how I start it up as I decided to try and follow tfgrower's suggestion of starting over with the air screw set to 3/16 using an Allen wrench (that was a great idea). 15 minutes after lighting I turned on my auger.

Here we have some shredded paper as a base with an old 32oz cup filled with loose stuff

Stuffed a wad of hand compressed shredded paper into the pellet chaff

Lit the bundle

Same, just without flash

Few minutes later


And here's a clip of how it burns right after the last pic was taken, let me know if you guys think the flames are bouncing too much (too much air)

command_z wrote:


I sift my pellets, just like I used to sift corn. So when I start the stove up, I take the sawdust and pellet pieces that fell through the holes and scoop it into a plastic cup. I get a little shredded paper and put it in the bottom and dump the cup into it (the shredded paper is to allow air up and stop sawdust from falling down). I then take same paper and roll them into tubes about 4" long and stuff them down and light the 4-6 tubes I shoved in there. Tubes burn up, go down to the shredded paper and the whole thing is aflame a few minutes later. Probably not the best method, but it works for me.

Buildup seems to take at least 1/2 day to be even noticeable at all, in the old days before the new blower it would be less than an hour, so I don't think it's how I'm starting it. I'm thinking it's something to do with the airflow inside the burn area and maybe the stuff I'm burning is a little sootier than what you guys are burning.

And yes, it's still the old auger. I'll be darned if I can find that second vise grip. The only thing I can think of is that the full corkscrew auger may be more consistent on feeding (sometimes it'll spit a few pellets or pellet pieces out and sometimes a whole bunch fall out at once, like in the video I posted where a lot fell out at once 20 seconds in and the flame shrunk). I haven't had any issues with the long pellet pieces which I think is due to my feed tube no longer getting any gunk/soot in it. Pellets fall down with a good speed, so even if a piece sits on the divider (only saw this once), the next batch comes flying down and knocks it out of the way.

tfgrower wrote:


I'm only guessing it's somewhat accurate. I got this little electric deep fryer recently and I was testing the fryer, set it to 375 and when the light went out, I hit it with the IR thermometer and it varied a little, but hovered around 375. So it should be close or both the fryer and the thermometer are in cahoots!

I'm not sure on the valve gap, I've been playing with it so much. I'm sure it's less than what yours is set for as that's where I started. Mine didn't close all the way (maybe some warping on the end or not enough PB Blast/lubricant on the threads?) and it closes up to where it's about a few pieces of paper wide as a gap. From there it's 2 full turns open. Seems if I try and turn it 1/2 a turn in or out, temps go down. At this point, I think I'll have to get a control switch as I saw a post from a year ago where someone did that and, while I think he was scanning the heat exchange tubes, he said he got more heat off of them with the Sparta blower running at 3/4 instead of full blast.

Original thread

Probably be some time before it comes in and I'll have to hit Radio Shack up for some quick connect spade connectors.

Ok, temp outside supposed to be below 30 tonight, so I have finally put it back up to 3 (though that might not be enough) and here's a short clip of what it looks like. Note that around 20 seconds in, if you listen close a bunch of pellets dropped in so the flame starts shrinking due to the new/cold fuel. About 30 seconds in it changes to an above shot since the side shot may not make it clear how much the flames move around.

Just as a reference (for myself and anyone else who may peruse this thread), still trying to tweak, but this is spot check of temps at auger setting of 3.

Top edge of the door


About 1 inch above the closed door


About 2 inches above the closed door

Here's a 30 second clip of my stove burning at auger 1. Disregard the sound, camera was picking up the room blower and making it sound worse than it really is. Not sure if it's burning well, the flames really move around a lot and I do see some blue at the bottom, so I think it's okay. I just never see huge flames or clean glass like you guys.

tfgrower,

I did see the Nesco version on the Sparta site, but you can't see any identifying information on it and no one seems to have replaced it and mentioned anything about the part number on it, so it's still a mystery, at least to me.

In regards to the pics, this is what mine looks like now. Some of the chunks finally turned a little gray and didn't seem to be burning down anymore (mine shrink a little while they burn off some more carbon when I stir them). Sorry that the pic seems bright, I had to use my camera flash so the areas around the fire could be seen. I'm still wondering what the secret is on the glass because the way the air flow seems to go, air goes up a little ways from the air wash (maybe 1/2 way) and then goes toward the back/baffle to exit out the exhaust, so I'm not sure how you guys are getting the air to go straight up the glass before going back. I also have to admit, that flame looks pretty big for auger setting of 4 (at least I think that's what you mean when you said #4), but then I haven't had to go higher than 3 yet, so I have no idea what mine would look like.

tfgrower wrote:


I don't have a Nesco negative draft motor, so I can't compare. I pulled the part numbers off the Sparta negative draft blower and the one off the Nesco positive draft motor.

Sparta = Fasco A082 / 7021-8293
Nesco positive draft = 7021-9258

The Sparta one is listed on Fasco's site as "Nameplate CFM 75" (but the sticker on the motor reads 70CFM) while I had to search Google for the Nesco positive draft and all sites indicate that it's 60 CFM. You have the Nesco negative draft, so not sure if you have the model number or a pic we can use as a reference if you are interested.

command_z wrote:


I do get clinker like stuff. Although honestly, I just stir the pot with the clinker tool. It probably causes some ash to fall through the holes, but I shutdown and clean out my stove about once a week anyway. Mine are dark black and crumbly. I'm cheap so to me, the dark black means not everything burned which is why I stir it instead of popping it out.

Here's an example. I just stirred it and the blue circles is the clinker chunks. Still trying to figure out your secret for super clean glass over several days of burning (or are you wiping it when you open the door?)

Ok, if you aren't cleaning out the pot every time and just scooping from the top every day until it gets cold and you burn 24/7 it likely is like tfgrower said. When you scoop, some ash would get pushed through the holes and fall down which would eventually restrict the airflow on one side since you always scoop in one direction.

I've been known to take a couple hours on my full cleanings, but even on a short cleaning, when the stove is cold I always do:

1) Burnpot/airwash plate
2) Clean heat exchange tubes
3) Brush down interior of stove (so thermal discs can feel maximum heat)
4) Clean behind baffle
5) Vacuum up all loose stuff from above that fell down
Total time 15-30 min depending how much soot accumulated

Then every so often I also do the brush up the exhaust (though now that I have the blower back there I guess it'll be connect shopvac blower only), empty hopper and check auger/bushing, make sure feed tube is smooth and clean (this seems much better now that soot doesn't go up there with the draft kit).

Once a season, open up room blower panels and vacuum, oil all motors.

I think that covers my routine at least off the top of my head.

command_z, when cleaning out the burn pot, I do the following:

1) Scoop all the loose stuff out
2) Use a metal stick (in my case, broken piece of coat hanger) and poke any holes that are not open
3) Vacuum loose stuff from the top
4) Pick up burn pot and swish it left and right to pour out any ash that fell into the box underneath so the ash falls out of the main air intake hole on the back
5) Use previous metal stick to rub around and knock anything that may stick through the air intake hole
6) Shake again and hold vacuum near it while shaking

Maybe overkill, but I've never had it lean to the left or right with that method.

Looks like a decent sized flame, what auger setting is that?

Do you have any modifications going (ie, tfgrower's version of the energy plate)?

When you clean behind the baffle, do you find more buildup on the right side of the baffle?

By the way, I notice your glass is really clean. Was this just fired up again recently? My glass always eventually develops a film of soot/ash, but it's a lot lighter/thinner with the negative draft kit then without.

command_z might be referring to me. I tried to burn some pellets on my lowest setting and my heat exchange tubes developed this shiny sheen to it after running for 12 hours. I admit, maybe it wasn't creosote, but I'm not sure what it was. After I altered the air setting to increase the amount going to the burn pot then ash or soot started accumulating and then I eventually brushed down the tubes on my next cleaning, so I don't know what it was. From what I can tell based on a dictionary, soot = fine powder with mostly carbon which makes it black, creosote = flammable tar substance from volatile gasses condensing. From what I can tell on my Google searches, chimney people, or at least chimney cleaners expanded "creosote" to three stages.

1) fine powder (what we probably call soot and technically could be flammable since it has carbon in it unless it's got a high ash/non burnable material content)
2) porous gummy/flaky (can still probably get it off with pipe brushes)
3) shiny tar substance that has to be scraped off

The interesting thing is, on wood (I guess it's the same for pellets since it's still wood) the gasses are given off when it burns at 500F and gasses burn up at 1100F. While I have no clue if it gets that high inside these stoves, it does say that if the flue gas drops below 250F (seems to be 150F-250F) then it's POSSIBLE for any unburnt gasses to condense and deposit on the pipes.

Source

Just a small update. It's gotten a little warmer out so I'm not running at 3 right now, but I took some scrap sheet metal I had laying around and jury rigged something similar to tfgrower's modification to try and force the air to go closer to the heat exchange tubes. I also added a couple of pieces of metal at the bottom as I noticed that the space under the baffle plate had no ash build up, so I can only assume SOME air was not going to the heat tubes and instead going under the baffle to go out the exhaust. I didn't take any official readings on my current setting of 2, but I think it feels warmer than before and the flames seem a little taller/longer than before.

10 minutes with Microsoft Paint.

Anyway, I actually opened it up a half turn to get those temps. Before they were maybe 5-10F lower. As I recall, the air screw only controls how much air goes into the burn pot, there is still a gap below where air comes out for the air wash system. I'm no aerodynamics engineer, but I think the blower is still taking out the same amount of air (it just makes up the difference from the air wash opening) which is why I'm thinking the blower is too powerful and needs to be slowed down. Just adjusting the air screw made it so the burn pot burned hotter so all the air inside is hotter. Until I find a good way to do that (unbelievably Lowes and Home Depot don't seem to sell fully variable fan speed controllers in store, just online only and for big money) I might try and take some scrap metal laying around and jury rig a temporary plate to extend the baffle like I saw you do in an old post.