I don't think my P38 is burning properly

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
I haven't followed this very closely, but I kind of doubt there's anything wrong with your stove. Being direct vent, I doubt it has anything to do with the draft either (unless you're running some screwy flue system or configuration). My guess is that if you do indeed have a problem, it's probably your pellets...
 
ducker said:
just called them, they say it's because of the lack of a good draft due to the temp outside being so warm (even though I tested it at night when it dipped below 50F)
He's checking with a tech and going to call me back. He wouldn't want to come out and find out it's only a draft issue as that wouldn't be covered under warranty. ( I also wouldn't want this... I could just wait until Mid October to call if need be)


The amount of draft can limit the amount of pellets that fall into the hopper?

Gio - I am getting more pellets, it's visibly different. At the 1 setting I can easily see the auger that is feeding the pellets. At a 3 setting, I can barely see it - as there are pellets and a larger flame in front of it.

My P38 runs as good with outdoor ambient temperature at 60* as it does at 40*. While it`s true that colder air outdoors can effect draft it doesn`t seem to make a noticeable difference with my stove. However , I am vented into a 2 story 7" round SS chimney and have always had excellent draft..
Since you can see more pellets fed into and being burned I`d have to say it`s a draft issue.
My neighbors brand new Englander is experiencing the same problem as your Harman. When it gets colder we plan to increase the draft to get a higher flame.
 
ducker said:
just called them, they say it's because of the lack of a good draft due to the temp outside being so warm (even though I tested it at night when it dipped below 50F)
That sounds really sketchy. I've been testing my install over the past few days in temps that were up in the high 70s-mid 80s. Last night's was to test the new programmable thermostat and it was 84 degrees with the thermo set at max (95). My stove (not a QF) worked fine.

I'd say that a stove that won't work well at 50F isn't up to the task of being a viable heating appliance.
 
Gio said:
ducker said:
just called them, they say it's because of the lack of a good draft due to the temp outside being so warm (even though I tested it at night when it dipped below 50F)
He's checking with a tech and going to call me back. He wouldn't want to come out and find out it's only a draft issue as that wouldn't be covered under warranty. ( I also wouldn't want this... I could just wait until Mid October to call if need be)


The amount of draft can limit the amount of pellets that fall into the hopper?

Gio - I am getting more pellets, it's visibly different. At the 1 setting I can easily see the auger that is feeding the pellets. At a 3 setting, I can barely see it - as there are pellets and a larger flame in front of it.

My P38 runs as good with outdoor ambient temperature at 60* as it does at 40*. While it`s true that colder air outdoors can effect draft it doesn`t seem to make a noticeable difference with my stove. However , I am vented into a 2 story 7" round SS chimney and have always had excellent draft..
Since you can see more pellets fed into and being burned I`d have to say it`s a draft issue.
My neighbors brand new Englander is experiencing the same problem as your Harman. When it gets colder we plan to increase the draft to get a higher flame.


Increasing the draft, is that something that can be modified on the unit itself?
This is vented in to a 2 Story chimney, which I've have no venting issues at all when starting a conventional fire in.

In the TroubleShooting section of the OPs manual - under the section "Feeder does not feed" #5 - Firebox draft may be too low for low draft pressure switch in feeder circuit to operate. Check for closed doors, loose or missing gasket on doors or hopper lid, faulty pressure switch.

So, if I hear the auger move at the correct time and duration, is there a different something that might just be limiting the amount of pellets that fall down in to my hopper? That slide plate?
 
ducker said:
Gio said:
ducker said:
Increasing the draft, is that something that can be modified on the unit itself?
This is vented in to a 2 Story chimney, which I've have no venting issues at all when starting a conventional fire in.

In the TroubleShooting section of the OPs manual - under the section "Feeder does not feed" #5 - Firebox draft may be too low for low draft pressure switch in feeder circuit to operate. Check for closed doors, loose or missing gasket on doors or hopper lid, faulty pressure switch.

So, if I hear the auger move at the correct time and duration, is there a different something that might just be limiting the amount of pellets that fall down in to my hopper? That slide plate?

Obviously there are other issues that could cause your problem and a skilled tech should be able to diagnose it rather quickly but since you aren`t going to get him to come right away and you`d like to find it yourself sooner you have to begin somewhere.
Assuming you have no restrictions , pellets are dry, slide plate works Ok, and there are no open doors or leaky gaskets you can begin with the correct draft. Not having a magnahelic to use , you could make small incremental adjustments to the trim pot yourself to determine if it effects the flame length and overall characteristics of a lazy vs too active a fire. If you can show that this indeed has a profound effect you can relay this info to the stove shop and he can make a more accurate adjustment.
But you might want to keep in mind the fact that if it is more problematic than just draft he could be quick to say your warranty is voided since you fooled with the board.
 
Gio said:
Obviously there are other issues that could cause your problem and a skilled tech should be able to diagnose it rather quickly but since you aren`t going to get him to come right away and you`d like to find it yourself sooner you have to begin somewhere.
Assuming you have no restrictions , pellets are dry, slide plate works Ok, and there are no open doors or leaky gaskets you can begin with the correct draft. Not having a magnahelic to use , you could make small incremental adjustments to the trim pot yourself to determine if it effects the flame length and overall characteristics of a lazy vs too active a fire. If you can show that this indeed has a profound effect you can relay this info to the stove shop and he can make a more accurate adjustment.
But you might want to keep in mind the fact that if it is more problematic than just draft he could be quick to say your warranty is voided since you fooled with the board.

not to keen on making modifications to the stove myself; especially if it might throw me out of warranty.


So I don't get it... those modifications aren't included in the install of a stove? hm... I'd think if you aren't suppose to modify something on the board like that, that the installer would make the necessary changes.


Right now, I'm going to hold tight I guess, and see if I can find a single bag of different pellets to try - I guess. That is unless I can get them to come out and tweek it.
 
ducker said:
Gio said:
Right now, I'm going to hold tight I guess, and see if I can find a single bag of different pellets to try - I guess. That is unless I can get them to come out and tweek it.
Hey - if you would meet me in Sturbridge I will bring you a fresh bag of pellets from my stash that I know are working well 'cause they're what I've been testing with.
 
before everyone jumps to conclusions.. ducker - when you're burning this unit how warm is it outside? Without a t-stat installed on the unit it will run off of flue temperatures. Depending on the temps outside depends on how hard the unit burns. As it gets colder I think you will see a big difference in the way you flames look. The video you shot looks like it's in maintenance mode, which is basically the unit burning at a specific flue temperature. So it met the flue temp that you had the unit set at, for argument sakes we'll say the units looking to reach 200 degrees in the flue. The flue hit that temp and the ESP probe sees that. Now the unit will drop down to the "maint mode" and basically burn at that temp. If you install a t-stat on this unit will run completely different with ramping the flame up and down.
 
DiggerJim said:
ducker said:
Gio said:
Right now, I'm going to hold tight I guess, and see if I can find a single bag of different pellets to try - I guess. That is unless I can get them to come out and tweek it.
Hey - if you would meet me in Sturbridge I will bring you a fresh bag of pellets from my stash that I know are working well 'cause they're what I've been testing with.

I'll keep that in mind, but if I can get my hands on a couple of different bags in my area I'd rather save both of us the gas (it would be a good 80+ miles roundtrip for me)
 
FireJumper said:
before everyone jumps to conclusions.. ducker - when you're burning this unit how warm is it outside? Without a t-stat installed on the unit it will run off of flue temperatures. Depending on the temps outside depends on how hard the unit burns. As it gets colder I think you will see a big difference in the way you flames look. The video you shot looks like it's in maintenance mode, which is basically the unit burning at a specific flue temperature. So it met the flue temp that you had the unit set at, for argument sakes we'll say the units looking to reach 200 degrees in the flue. The flue hit that temp and the ESP probe sees that. Now the unit will drop down to the "maint mode" and basically burn at that temp. If you install a t-stat on this unit will run completely different with ramping the flame up and down.

Well now, that may be but how do the above comments account for my P38 operating perfectly well in any temperatures and responding to settings quickly and accurately ? On setting #1 my stove delivers a maintence burn(very low) and on #3 the flame is like 4" high and on #5 and Turbo modes the flame gets very high and touches the heat exchanger.
 
FireJumper said:
before everyone jumps to conclusions.. ducker - when you're burning this unit how warm is it outside? Without a t-stat installed on the unit it will run off of flue temperatures. Depending on the temps outside depends on how hard the unit burns. As it gets colder I think you will see a big difference in the way you flames look. The video you shot looks like it's in maintenance mode, which is basically the unit burning at a specific flue temperature. So it met the flue temp that you had the unit set at, for argument sakes we'll say the units looking to reach 200 degrees in the flue. The flue hit that temp and the ESP probe sees that. Now the unit will drop down to the "maint mode" and basically burn at that temp. If you install a t-stat on this unit will run completely different with ramping the flame up and down.

Hm, great point, BUT if I have it set to 3- and it's feeding pellets for 16 seconds every minute (ie. I can hear the auger motor run for 16 seconds a minute), and always 16 seconds every minute; what would the ESP probe change? The amount of pellets allowed down in to the Auger past the plate? Essentially I'm seeing "short fast flames" at pretty much any setting aside from 5/turbo.

Which leads me to believe that it's not flipping down in to maintenance mode, but perhaps not allowing enough pellets to drop down in to the auger (due to the plate?)
 
ok... here's the feedback I got from the installer.

He figures it's most likely the pellets.
1) they might of gotten slightly damp
2) there might be sawdust down where the steel plate is causing problems with the plate moving
3) there might be some longer pellets causing a bridge over the plate, thus restricting the flow of pellets
down to the auger.



I'm going to see if I can find a couple of different brands of pellets to give a try before I actually put in a service call to them and have them come out.

I'm thinking it might be the stove too, as when I explained to him how it looked at the lowest setting, it sounds as if I'm really not getting enough pellets. as He would expect about half or more of the auger to be hidden behind pellets, and I see it clear as day.
 
here are a couple of pictures of it on Maint burn... (setting of 1)

mainburn1.jpg


mainburn2.jpg


mainburn3.jpg
 
so after testing another pellet (energix - hardwood) I experienced the same exact type of burn.
I have 1 other pellet type . Energix - softwood that I'm going to give a try tonight (if I can)

I noticed that after my last run, there were some pellets still in the hopper (not many at all) down by the slide plate,
but the fire already died out. I was kind of surprised by this. I figured if you let the fire burn out, that it would burn all the pellets in the hopper/auger
before going out. Is this the case?

Also, the tech that I spoke with that did the install talked with me about bad pellets. saying they should have a shiny/glossy finish. If the outside of the pellet is rough, its because because they got a bit damp from moisture and then dried back out.

When I view the pellets I have (instaheat) as well as the ones I recently bought at a hardware store - it appears that the majority of them are in fact that nice glossy finish on the outside. And that there are a couple here and there that are a little rougher around the edges so to speak. I figure that they should burn decently, and that it wouldn't only fail to burn well if the majority of the pellets were infact these moisture damaged pellets.

It would just be too crazy that 2 different brands, purchased from 2 different locations, at different times, had the same issue... right?
 
I would say your pellets are probably ok then.
I turn my top knob all the way up
and the bottom knob to about a 3 and then after an hour to an hour and a half I have the 4 inchs or so of flames.
Did u have the blower knob all the way up?
 
rayttt said:
I would say your pellets are probably ok then.
I turn my top knob all the way up
and the bottom knob to about a 3 and then after an hour to an hour and a half I have the 4 inchs or so of flames.
Did u have the blower knob all the way up?

yep - no 4 inch flame - again I'll test the softwood pellets tonight, just to make sure.

Hell, I even checked a couple more bags of the 3 tons I got down stairs, they all check out fairly well (a bit more dust in some then others, but I attribute that to the fact that they are on the slightly cheaper side)
 
check to see if the feed motor is installed proprely.

I believe some of the feed motors were manufactured with too short of a flat portion on the output shaft. This allows the shaft to spin freely whenever there is resistance against the auger rotation.
To fix this - Loosen the cam block bolt, I think it's a 7/16” bolt. Pull the feed motor out to where you can align the bolt from the cam block with the flat portion of the motor shaft. Re-insert the feed motor. Make sure you look at the depth of the flat portion of the shaft, and insert the motor to where the bolt will still tighten on to the flat portion. What you’ll end up with is a gap between the back of the motor casing and the end of the auger shaft, I think you should have about an 1/8" gap.

You can also check to see if the cam bearing is hitting the pusher arm properly. If it doesn't that will also reduce the amount of feed the stove will get..
 
FireJumper said:
check to see if the feed motor is installed proprely.

I believe some of the feed motors were manufactured with too short of a flat portion on the output shaft. This allows the shaft to spin freely whenever there is resistance against the auger rotation.
To fix this - Loosen the cam block bolt, I think it's a 7/16” bolt. Pull the feed motor out to where you can align the bolt from the cam block with the flat portion of the motor shaft. Re-insert the feed motor. Make sure you look at the depth of the flat portion of the shaft, and insert the motor to where the bolt will still tighten on to the flat portion. What you’ll end up with is a gap between the back of the motor casing and the end of the auger shaft, I think you should have about an 1/8" gap.

You can also check to see if the cam bearing is hitting the pusher arm properly. If it doesn't that will also reduce the amount of feed the stove will get..

Awesome feedback FireJumper - if my stove was out of warranty... I'd be all over checking this out. But it's only a month old with maybe 10 hours of total burn time so far.
I'd rather have a service tech check in to that.
 
dude .....i'll say it again call the people who installed your stove.they should have made sure your stove worked correctly when installed.
that 's what you paid for.
 
Looking at the pics it seems like the amount of pellets being delivered is less than what should be in the pot. My lowest setting maintenance burn has a short flame but it is uniform and spread wider with more pellets than what your pictures show .
It looks to me like there could be a pellet feed problem.
 
CelciusMaximus said:
dude .....i'll say it again call the people who installed your stove.they should have made sure your stove worked correctly when installed.
that 's what you paid for.

Already did, and planning on having them come out. Problem is, I don't want to shell out a $75 or whatever fee they charge for a service call if it's simply crappy pellets I'm using. Being a pellet newbie, I have no way of knowing!

But you're right, that is what I paid for.
 
they are coming out this Wednesday to take a look at the stove. I hope they can figure it out. They don't want it running when they arrive, I think I'm going to empty the majority of the pellets out of the bin too, incase they want to look at that trapdoor and what not back there..

Hopefully they find something cause I don't want to have to shell out a wad a cash for them to tell me.. I'm imaging things :)
 
This is exactly why the P38 isn't my fav stove. Once you get them tuned in they work great. Getting there can be a pain. First off I doubt the pellets are the problem. As long as you can here the tinkle sound when the auger motor turns you are getting fuel. It could be as simple as too much draft which can be adjusted by turning down the pot on the contrl board. DO NOT DO IT WHILE PLUGGED IN!!! there are exposed electrical contacts on the board that like to bite. Ask me how I know. You do need to give the stove time to adjust after you change the heat output setting, 1/2 hour may not be too long. The stoves react and ramp up or down in stages that may seem to take too long. The esp probe may be giving the control board a bad signal and causing the stove to burn cooler than it should. The problem with the p38 vs. the rest of the Harman line is it's more difficult to trouble shoot. Once you get it right you should be very happy with it, I know of several with 8 to 10 years of operation with maybe an exhaust motor replaced one time.
 
Status
Not open for further replies.