Pelpro pp130. Lazy flame. Overflowing burn pot. All of sudden Only 1 ton pellets in.

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Ours did the same after the first 10 bags or so. Every so often it still does. I vacuum it then crank it all the way up for 2 hours. Seems to burn all build up out of it. Burn it hot then adjust to liking

View attachment 305193 View attachment 305194
I burn mine on high some as well.

I have 2 stoves. Turn this one off at night. Then kick it on high in the morning for a bit. Then back to low for the day
 
I did a little test on the stove (Pelpro PP130/MFG Date 2/2015) to see if I could better understand just what the trim dial effects. A couple of notes on the test to be aware of:
  1. I did not verify if the the auger turns the same amount every time it is commanded to to turn. So I do not know if it in fact does incrementally rotate the same amount every time it is commanded to do so.
  2. The second and and the last setting values were the same in order to see if the sampling was accurate. Other than the RPM speed the dwell time between auger cycles was consistent.
  3. There was already an existing white line on the fan on top of the combustion fan motor that I used for the reference for the motor RPM using an optical tachometer.
  4. I waited 5 to 6 minutes in between tests after I made any trim and/or T-stat adjustments.
I would like to know if this is accurate or how it compares to others who may have done this, if anyone has. Other than the low to thermostat setting it really appears there is no significant change in fan RPM by the trim adjust and there is slight dwell time differences in the the off time of the auger motor. If that is the case, it would be nice to have a better control for the auger feed rate. In my case when the wind blows out of the North East I would like to have the fan running at full speed and the dwell time between auger feeds decreased a little more than the current trim adjust allows.

Has anyone every modified a Pelpro with a custom auger timer control or something similar?
I use mine in a good sized shop and really could care less about the thermostat as in my case it is either on low when I am not there or it runs full on even if the setting is on one just due to the size of the garage and temp when I do use it.

Trim Adjustment settingT-Stat SettingSeconds between auger feed commandsCombustion Fan RPM
-3​
Low
6.09​
2681​
-3​
4​
4.11​
3131​
`+3​
4​
3.6​
3091​
0​
4​
3.81​
3086​
-3​
4​
4.08​
3097​
 
I did a little test on the stove (Pelpro PP130/MFG Date 2/2015) to see if I could better understand just what the trim dial effects. A couple of notes on the test to be aware of:
  1. I did not verify if the the auger turns the same amount every time it is commanded to to turn. So I do not know if it in fact does incrementally rotate the same amount every time it is commanded to do so.
  2. The second and and the last setting values were the same in order to see if the sampling was accurate. Other than the RPM speed the dwell time between auger cycles was consistent.
  3. There was already an existing white line on the fan on top of the combustion fan motor that I used for the reference for the motor RPM using an optical tachometer.
  4. I waited 5 to 6 minutes in between tests after I made any trim and/or T-stat adjustments.
I would like to know if this is accurate or how it compares to others who may have done this, if anyone has. Other than the low to thermostat setting it really appears there is no significant change in fan RPM by the trim adjust and there is slight dwell time differences in the the off time of the auger motor. If that is the case, it would be nice to have a better control for the auger feed rate. In my case when the wind blows out of the North East I would like to have the fan running at full speed and the dwell time between auger feeds decreased a little more than the current trim adjust allows.

Has anyone every modified a Pelpro with a custom auger timer control or something similar?
I use mine in a good sized shop and really could care less about the thermostat as in my case it is either on low when I am not there or it runs full on even if the setting is on one just due to the size of the garage and temp when I do use it.

Trim Adjustment settingT-Stat SettingSeconds between auger feed commandsCombustion Fan RPM
-3​
Low
6.09​
2681​
-3​
4​
4.11​
3131​
`+3​
4​
3.6​
3091​
0​
4​
3.81​
3086​
-3​
4​
4.08​
3097​

I won't be home from work until after the 1st to check and compare. My PelPro was built in 21 and I have not done the software update. I did get between 2980 and 3100 rpm on exhaust fan when I checked it with little to no change with trim settings. I will check for sure when I get home.
 
I won't be home from work until after the 1st to check and compare. My PelPro was built in 21 and I have not done the software update. I did get between 2980 and 3100 rpm on exhaust fan when I checked it with little to no change with trim settings. I will check for sure when I get home.

Shoe1757

Thank you very much for the response. As you stated I saw no big difference in fan RPM either and the most was between the low setting and any number from 1 to 10 on the thermostat. I think Pelpro would serve the customer better if they just put a variable dial for the auger feeder that would go from as long as 60 seconds or more to as fast as two second intervals between auger feeds. And for the fan put a small VFD with a motor which has a rated RPM speed of 3600 that can pull about 100cfm or more. The main blower needs to be something that can move at least 500 CFM or more to make it worthy as well. I think the fan they use only rated for like 265 cfm. And then just have a hi and lo setting and not worry about trying to control it with a thermostat as I believe, although a novel concept, more of a hit an miss than not. If they wish they could just add a terminal base for the option to wire in a external thermometer that would cyle it between lo and hi and if the customer wants it they can add and in if not they don't.
Thanks again for the reply and would be interested in what you find on yours if you test it.
 
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I had trouble again with the stove feeding the pot more pellets than it could burn if set any higher than on low. I had throughly cleaned it yesterday and adjusted the trim as I documented the changes above but it would continue overfeeding. This afternoon I shut it down cleaned just the burn pot and around the bottom and sides. I then pulled out the baffles and drilled five, 1/4" holes from left to right about two inches down from the top on the lefthand baffel that has the exhaust outlet behind it on the bottom. I work on boilers and air heaters in my profession and realized that we give them unrestricted air to feed those burners and noticed that this combustion fan, which works basically in reverse of what I work on, was a bit restricted on the suction side as it has to basically suck around the edges of the baffel(s) in order to pull air through the burn pot for the combustion. Generally speaking your combustion air should not be restricted and should be regulated by the fan speed. After I did that, I set the trim adjust to -4 and the dwell time between stop and start of auger feeds is 4.37 seconds and the fan rpm showed 3104. It has only ran a few hours now on 4 of the thermostat and the burn pot has been pretty consistently staying at a maintained level of pellets and not building up. The frustrating part is, about a week or little longer ago I had the same issue and it ended up being -2 trim setting and worked good like it is now up to about two days ago. And there had been some cleanings in between but it just kind of goes off the deep end and then comes back after a while.
 
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I totally understand the frustration. But I do believe the green pulls from a gap below the baffle and above. Holes would definitely still add more flow and I can't wait to see your results! Hopefully it doesn't cause too much ash in the fan or exhaust pipe. I feel like these could be great "budget" stoves with a little tuning. When I get home I will be playing around with attempting to increase fan speed, different burn pot ports, and manual auger delaying.
 
I must have the PP130 unicorn. Mine has had no real issues that required any modification etc for the past 3 winters.

I say "real issues" because I did have to do a few things over the past 3 years.
1. Had to replace the room blower and the ignitor. Both simple fixes.
2. Had an issue with it not registering a flame. This came down to the stove not being clean. Ash in the exhaust blower housing was insulating the sensor. Cleaning it prior to heating season has made this a non issue.

When I first moved in to my house it already had the PP130 installed. I had some issues with overflowing pellets etc until I figured out how to make sure it was clean and had good air flow. Since then I can run it on any setting with no issue.

Mine is direct vented from the back of the stove and out the wall. I wonder if this helps since there is no restrictions.
 
Well other than my wife breaking the hopper switch, I can't say I've had any real issues yet. The burn pot did over flow sort of one day, was burning still, but the ledge was covered in unburnt pellets. I am just looking for ways to make it better and a little more efficient
 
In regards to durability the only thing that has ever failed on mine is the door latch broke. I have a "T" out of the stove to a 5' vertical, a 90 and a 3' horizontal out the wall. So some of my issue may be is it has work harder to vent out of that but from what I could get from installation instructions that should be ok. I did want to go straight out the wall but it being on the north side I was a bit concerned with snow piling up and it is in a traffic area as well. I believe you get a much better draft than I do with it straight out the all. I have the stove on a stand so the pipe on the outside is about 7' above ground level so you won't run into if you are walking by. I considered the extra dust in the fan as well and that is in part why I put them up closer to the top instead of just a bit close to the top of the burn post were I initially thought of installing them. It's been below zero here the past few days and it has done pretty well with the T-stat on 3 or 4, I could set it on one and it would never heat it up enough at this time of year to throttle down. You peeked my interest in adding a little positive air to the intake and I did experiment with that in shorts burst of a few minutes at a time and it does make noticeable difference. It would take much flow and I think if you had a fan that you had a means of adjusting the airflow probably would work.
In regards to the software deal I vaguely recall that and I may have upgraded it as I remember a few years ago messing around with plugging a USB in to the port on the card behind the panel. I noted what I have read on the subject that it claims to be for a model 130B I believe and my does not have B in the model. I could be wrong on the model nomenclature other than I do remember there being "B" in the model I have seen referenced that has the firmware upgrade option. So if I did talk to Pelpro, and I may have cause I have had this stove a few years and it has lasted longer than my memory, I may have done the update but again I may not have.
Now that I got to where it will consistently keep the burn pot clean for several days now on low a least, I wish I would have order the hopper extension.
Thanks for all the feedback, ideas and info you guys have shared. I will keep you all posted on any changes, experiments or tests I may do in the future but it has been running fairly well as of late and if we don't get to many NW wind storms it will probably keep chugging along pretty good it appears.
 
In regards to durability the only thing that has ever failed on mine is the door latch broke. I have a "T" out of the stove to a 5' vertical, a 90 and a 3' horizontal out the wall. So some of my issue may be is it has work harder to vent out of that but from what I could get from installation instructions that should be ok. I did want to go straight out the wall but it being on the north side I was a bit concerned with snow piling up and it is in a traffic area as well. I believe you get a much better draft than I do with it straight out the all. I have the stove on a stand so the pipe on the outside is about 7' above ground level so you won't run into if you are walking by. I considered the extra dust in the fan as well and that is in part why I put them up closer to the top instead of just a bit close to the top of the burn post were I initially thought of installing them. It's been below zero here the past few days and it has done pretty well with the T-stat on 3 or 4, I could set it on one and it would never heat it up enough at this time of year to throttle down. You peeked my interest in adding a little positive air to the intake and I did experiment with that in shorts burst of a few minutes at a time and it does make noticeable difference. It would take much flow and I think if you had a fan that you had a means of adjusting the airflow probably would work.
In regards to the software deal I vaguely recall that and I may have upgraded it as I remember a few years ago messing around with plugging a USB in to the port on the card behind the panel. I noted what I have read on the subject that it claims to be for a model 130B I believe and my does not have B in the model. I could be wrong on the model nomenclature other than I do remember there being "B" in the model I have seen referenced that has the firmware upgrade option. So if I did talk to Pelpro, and I may have cause I have had this stove a few years and it has lasted longer than my memory, I may have done the update but again I may not have.
Now that I got to where it will consistently keep the burn pot clean for several days now on low a least, I wish I would have order the hopper extension.
Thanks for all the feedback, ideas and info you guys have shared. I will keep you all posted on any changes, experiments or tests I may do in the future but it has been running fairly well as of late and if we don't get to many NW wind storms it will probably keep chugging along pretty good it appears.
Wow that's awesome to keep it for 7 days even on low! As of two days ago I have had my wife just leave it on high to maintain 66-70 throughout the whole house and right at about 24 hours (Roughly 3 bags+/-) she noticed the pot building up pretty high and has to clean it.

I plan on building a shroud with a computer fan that I will wire in a controller for on my intake side. I may even run the intake outside and make the fan in line. But before I get to that I have to finish sanding and rebuilding my Quadrafire contour to install in the basement or move the pp130 to the basement and install the contour in its place in the garage as it has a smaller hopper and lower BTU/hr output.

I do recall the update being for the pp130b, but I could not find the difference with the 130b model so assumed maybe that's the full model name.
 
I plan on building a shroud with a computer fan that I will wire in a controller for on my intake side.

Wow, Change a negative draft stove to a positive draft stove!!
I wonder why so many years ago stove manufacturers changed from
blowing air into the fire to sucking air through the fire?????????
Let's see some reasons
Smoke and off-gasses escaping into the room!
Fire being blown into the hopper past the auger!
Overriding safties! Maybe you could think of a few.
 
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Wow, Change a negative draft stove to a positive draft stove!!
I wonder why so many years ago stove manufacturers changed from
blowing air into the fire to sucking air through the fire?????????
Let's see some reasons
Smoke and off-gasses escaping into the room!
Fire being blown into the hopper past the auger!
Overriding safties! Maybe you could think of a few.
Couldn't think of any, so here's a few that make those irrelevant as well.

I would need a pretty significant positive pressure fan/pump to make any of those things happen.

Path of least resistance for air flow is still the exhaust, where it is being drawn by a substantial fan, so likelyhood of it going up the auger into the hopper is highly unlikely. In the even of say a total blockage in the exhaust and exhaust fan stopping, I'm still not applying pressurized air, so still highly unlikely along with wood gasses and smoke being released.

And my favorite...

All of my safety switches are still intact. Which my favorite being the vacuum switch! If I were to ever force so much air into the chamber that I even got to the point of losing vacuum pressure (let lone actually PRESSURIZING the chamber) the vacuum switch would break contact and shut down.

I am not recommending anyone try ANY of my ideas. I am simply giving a synopsis of testing I've done.

The man who invented the wheel never perfected it.
 
The man who invented the wheel never perfected it.
You are right
But that's why they went from pos. draft to neg draft

What happens when and if the exhaust gets plugged?
It's your family to experiment with Just saying
Maybe you're a good candidate for the darwin list.
 
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You are right
But that's why they went from pos. draft to neg draft

What happens when and if the exhaust gets plugged?
It's your family to experiment with Just saying
Maybe you're a good candidate for the darwin list.
Yea maybe my whole family will burn alive, good joke!

Exhaust gets plugged, still no FORCED AIR. You can only put so much water in a glass. No airflow out, no airflow in, useable oxygen is spent and flame smothers it's self. Loss of vacuum causes auger feed to stop, worst case scenario it overheats and pops snap disc. Also I have a old school fire suppressent system set up in the garage and basement.
 
Exhaust gets plugged, still no FORCED AIR.
You have a perfectly sealed stove
No air wash, door and ash pan seals perfect
Hopper lid sealed? No leaks anywhere
I won't argue with you I just feel you are taking two steps back
trying to put a square peg into that round hole.
Trying the same thing over and over getting the same results
What's that called? ----------- You fill in the blank
 
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You have a perfectly sealed stove
No air wash, door and ash pan seals perfect
Hopper lid sealed? No leaks anywhere
I won't argue with you I just feel you are taking two steps back
trying to put a square peg into that round hole.
Trying the same thing over and over getting the same results
What's that called? ----------- You fill in the blank
If you are referring to "insanity" that definition is only of Mr. Albert Einstein and not the legal definition. Also with the study of quantum physics we know that it is most certain that repeating the same thing over and over will produce a different result at some point. Maybe after 5 billion tries, but still.

No ash pan on the PelPro unfortunately, one of my favorite features on the Quadrafire. I think if you saw the set up you would understand the concept a little better, a lot of things can't be fully represented. It was set up similar to as if you had an OAK and there was a breeze blowing. I have actually moved that stove into the basement and with the OAK hooked up and with the high winds we've had over the last 2 days, it is noticeably forcing air in more so than my fan blowing towards the intake.
 
I agree with the high wind and OAK being plumbed out side. Definitely going to be positive air flow through it with the winds we have experienced up north here over the past few days. With that being said mine has not seemed to been having issues as of late with the NW wind snuffing out the flame or working against the exhaust fan trying to push air out the chimney like it used to.
The hopper lid on a pelpro does not "seal" like other brands may, I guess they assume an auger full of pellets will seal it well enough. I like the comment about the guy who invented the wheel because in regards to the pelpro pellet chute, it should have a couple of offset baffels in it that allows the pellets to fall through but would help prevent hot embers from going up the chute.
Here is how you start an auger fire going. Let the stove run turned up so the pellets eventually build up to the top over many hours so there are hot embers filling the pot, this could take up to a whole day possibly. Open the hopper lid then add a little to much forced air to the OAK and walla you should have an auger fire in short order and the overtemp snap switch in the auger housing will open, shutting everything down. If you have a test cable built to run your auger then you can unplug your auger, plug that in and kick the auger on to evacuate the burning pellets.
All the boilers and air heaters I work on are positive air flow for the combustion air and the pellet stove is the only one I have personally experienced that uses a negative air flow system, which in regards to cost is probably more expensive to create a blower assembly for to be capable of handling high heat. I would agree an exhaust fan that had the capability of moving much more air than the one used on the pelpro would be more desirable but you would have to either be in the pellet stove business or one of your buddies works at the plant where pelpros' are made in order to figure out who is making the fan assembly for them in order to get you one with a higher cfm that also fits the same foot print. OR find one that fits the 3" chimney vent and plumb it in there instead.
About the only things you have to make sure that are sealed are the door, the burn pot on the housing it sits in and the combustion fan housing.
If I were to install a fan on mine to add a little more air I would wire it to operate in conjunction with the current fan, the vacuum switch and not run when on low.
In doing some maintenance on mine. I noticed the vacuum switch which is used to prove airflow is present, only shuts off the auger feed if the switch is open. If the switch is open it will not shut down the unit per say until the fire burns out due to lack of pellets. I point that out because I thought it probably was designed with a timer in circuit so that if something like the door comes open or whatever it would shut down the heater like the over temp switch does. So if I were to add and external fan I would probably include that in the limit string for the fan so if a positive pressure is seen inside the chamber it would shut that fan off so as not to further exacerbate the loss of airflow issue. If you were to add to much air from the paf, the chimney path plugs off or you loose enough seal somewhere like around the door you wouldn't want that fan to keep running.
One last note I will pass along, I did have an issue with my auger motor not working the other night. Basically it just quit turning and was getting voltage. So I removed it and pulled it apart and all the gears were intact but the grease seem pretty stiff. So I cleaned it up and relubed it and it ran as designed when tested, prior to that it appeared to struggle when I first tested it. I then pulled the auger since I was that far along and found the bottom bushing had some scoring going on so I polished both ends of the auger shaft and put it back together with a sparing amount of high temp grease. There is a flat disk that is part of the auger on the bottom that rides against the nylon gasket on the bottom mounting plate that had built up with pellet fines, it was packed together and about the size of a 1/2" washer or so and I cleaned that up. I am going to order a new bushing and will probably check that at least every other year and clean it if necessary. That is the first time I have had that off since I got the stove in 2016.

Here is the frustrating part, for the last week or so mine seemed to be doing well, no burn issues, keeping up heat wise and so on with the trim dial at -4. After I did my cleanup and work on the auger it is running best on +2. I had a pellet stove years ago, forget the brand, in a house I owned and it just had a dial for the pellet feed control and that was it. You did have to also mess with it but at least it was more straight forward and had more noticable effect than the pelpro and the trim pot. It would be nice if they would share there program for there firmware so people could at least understand the control side of the stove. I don't believe pelpro has any field techs traveling around doing repairs or installs so you would expect them to have a world class tech support center and documentation on there stoves. But from what is have gathered from others is they basically take your symptoms you report and sell you parts.
 
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One other note on up sizing the exhaust fan would be that you would have to somehow compensate the pellet feed also. I believe a little more air would help on these stoves when the dial is turned up but when they go to low fire or are set on low you would have to be able to either throttle the fan back to match the oem CFM or increase pellet feed. Again with out the support from pelpro to allow you to modify the firmware then you would probably have to install your own timer circuit for the pellet feed.
 
I just read this entire thread, very interesting and informative, especially the combustion air and draft discussions.
The only thing that I have to add, concerning forced combustion air vs. forced draft is, all modern gas furnaces, that I've worked on, use a forced draft/exhaust blower.
The draft must be made, a vacuum or sail switch must prove, before the ignition and gas valves can operate.
 
The vacuum switch in these basically interrupts the auger feed and stops the feeding of pellets so long as it sees no vacuum. An update on mine, it has been doing quite well over all and very good when we had a stretch of days with the wind howling out of the North West. Generally a NW wind, as I stated previously, will just about snuff out the flame even if it was completely clean. On those days we had the strong storm come through I did notice it affecting the flame a bit but not nearly as much as it did pervious to few mods I did for airflow. The other interesting point I noticed is I don't see any significant increase of ash in behind the baffles in the path of the combustion fan intake area or chimney, and that is with not cleaning it out until the ash gets about 3/4 or so up the side of the burn pot housing. The most I have seen in the burn pot after letting run several days is maybe a 1/4" built up in some areas around the holes.
 
The vacuum switch in these basically interrupts the auger feed and stops the feeding of pellets so long as it sees no vacuum. An update on mine, it has been doing quite well over all and very good when we had a stretch of days with the wind howling out of the North West. Generally a NW wind, as I stated previously, will just about snuff out the flame even if it was completely clean. On those days we had the strong storm come through I did notice it affecting the flame a bit but not nearly as much as it did pervious to few mods I did for airflow. The other interesting point I noticed is I don't see any significant increase of ash in behind the baffles in the path of the combustion fan intake area or chimney, and that is with not cleaning it out until the ash gets about 3/4 or so up the side of the burn pot housing. The most I have seen in the burn pot after letting run several days is maybe a 1/4" built up in some areas around the holes.
Is this still with running your burn pot with .150 holes in the bottom and everything else welded up?
 
Is this still with running your burn pot with .150 holes in the bottom and everything else welded up?
Yes it has been running all winter and doing quite well. As I stated in an earlier post it really made a difference for me when the wind is out of the north west, the flame doesn't get snuffed out by the back draft like it used to. I had to experiment with the trim a bit and found the -3 to -4 is where it works best. I was actually looking at hopper extensions for them since I don't have to shut it down everyday to clean the burn pot out like I used to. I could never justify adding a hopper extension if I had to be there to service it daily anyway I figured I can also throw in another bag of pellets after I cleaned it. I generally don't shut it down to clean it until I see the ash in front of the burn pot build up an an half to two above the bottom of the glass. Depending if it is set on low or turned up really determines how many days it will run before it gets that much build up in it but I generally don't have to clean more than twice a week and in some cases once if it hasn't be turned up above low much.
 
Yes it has been running all winter and doing quite well. As I stated in an earlier post it really made a difference for me when the wind is out of the north west, the flame doesn't get snuffed out by the back draft like it used to. I had to experiment with the trim a bit and found the -3 to -4 is where it works best. I was actually looking at hopper extensions for them since I don't have to shut it down everyday to clean the burn pot out like I used to. I could never justify adding a hopper extension if I had to be there to service it daily anyway I figured I can also throw in another bag of pellets after I cleaned it. I generally don't shut it down to clean it until I see the ash in front of the burn pot build up an an half to two above the bottom of the glass. Depending if it is set on low or turned up really determines how many days it will run before it gets that much build up in it but I generally don't have to clean more than twice a week and in some cases once if it hasn't be turned up above low much.
I've been doing a bunch of testing with modifying my burn pot. So far the best results I've gotten were with 3 holes above igniter welded, angle piece in rear blocked off, front angle cut off and welded, 6 holes in the bottom. Also used a carbide Burr to angle all the existing holes upwards.

I noticed how much the speed on the convection blower changes. I am going to install a relay so it runs max speed any time it is on and see how that works. Once I see how that works, next will be wiring in a thermostat so that it runs on high when called on for heat, and then shuts down once temperature is set. I leave it on setting 1 or 2 to keep my house at 72 and I get a lot more.ash with a low flame. Once I figure out the relay wiring for max convection fan speed and how to wire in the thermostat I'll make a post if others would like to try.
 
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