Harman P43 difficulties. six blink status message/fire going out.

[bags]

Has anyone had a room sensor actually go bad or know of a confirmed kill? All I have seen is connection problems mainly and they can be a tricky chasing the electrical ghost problem.

 

[Bioburner]

None that I can remember. Usually a connection or pet problem.

 

[bags]

Like I've said before. Free puppies cost money and time just like free firewood.

 

[Harman Lover 007]

Not necessarily. If you'll look at other threads on the site you'll find that a faulty or disconnected room temp sensor has, at times, affected stove temp operation.

Just because there are other threads here that describe said condition, there were likely other underlying issues that led to those conclusions. Stove temp mode is a totally separate operation of the stove and a missing, disconnected, or otherwise malfunctioning room temp sensor will not affect stove temp operation. A bad ESP, however, will.

 

[ttdberg]

Humor me. Try another brand of pellets. Just pick up a few bags and see if the situation changes. Pellets with high moisture content will cause this behavior in my P68. I have had issues like you are describing in the past, and after spending countless hours troubleshooting everything else in the stove, it was the pellets causing the issue all along.

 

[Bioburner]

Humor me. Try another brand of pellets. Just pick up a few bags and see if the situation changes. Pellets with high moisture content will cause this behavior in my P68. I have had issues like you are describing in the past, and after spending countless hours troubleshooting everything else in the stove, it was the pellets causing the issue all along.

Its a cheap simple test to rule out fuel issue.

 

[F4jock]

Its a cheap simple test to rule out fuel issue.

Just as the finger pinch / ice cubes test will rule out the room temp sensor.

 

[digitys]

Just to chime in here.... We battled this problem for over a month earlier this burn season with our XXV. We cleaned everything top to bottom including esp probe, etc etc.

It ended being the pellets we had left over from the year before. I tested by cleaning it completely, then putting in a few new bags. Never happened again! As soon as I put a bag of the others, within 4-6 hours she would shut down and 6 blink. We ended up mixing the bad pellets slightly with our good ones as I didn't have the heart to toss he bags. All has been well since!

 

[camotan]

Thanks for all the advice and encouragement. I was pretty worried about the stove but think things will work out now.

I wanted to give an update on the situation. I burned the stove in room temp mode for about six hours yesterday while I was home. There was no problem. The stove was not heating the house--I had my toyo set to 70 and the stove set to around 60--65. The idea was to see if the stove was going out during the maintenance burn as it has no problem bringing the room up to the desired temperature. It sat on the maintenance burn for the whole time I was home and went out sometime while I was gone. I came home to a cold quiet stove and a six blink status light (and almost a full fuel hopper). Now that the stove was cold, I tried the dollar bill test (correctly this time). And it was stuck pretty firm on the latch side of the door, but slipped right out easy on the hinge side and on the bottom. So. Gaskets are bad for sure.

Last night though, I tried changing from room temp to stove temp and left it on a low setting all night. This time, the fire burned out again, but there was no error code at all--The status light was off--no blinks at all.

Would that rule out a temperature probe issue? I did check my connections and they seem good. I'll do a ice water/warm hand test later on once I start the stove up just to be sure. As a side note, is it ok to solder the temp probe to the connector? It is a really weak connection and a firm tug would pull the wire right out, leaving the plug in the socket on the back of the stove. I have a picture below but I'm sure you know what I mean.

Anyway, I bought some new door gaskets this morning and have spent the past several hours scouring out the old cement. I applied the new cement and the door gasket and the stove has about two hours to go before it's set. I'll try a dollar bill test again before I light it.

If that doesn't work, I'll try buying a few new bags of pellets but if that's the problem I am going to be profoundly annoyed as I have about $600 of my current supply left. I have burned through a ton so far without a problem. I keep them stored on pallets with plastic covering them. It's pretty cold out, and there's snow, but they really shouldn't be getting wet as the water's all frozen. I've never had trouble keeping them outdoors before and this is how they're stored at all the shops in town and at our plant. I'm not thrilled with my arrangement but haven't gotten around to setting up a storage area yet. Maybe next summer...

But if _that_ doesn't work I guess it's time to swap out the ESP probe. I'm also going to get that low voltage draft adjustment done as soon as I can--that's going to be tricky though because I have to stay home from work and have someone come by unless I buy my own equipment and learn how to DIY. I haven't had this problem before though, and I've never had the draft adjustment done, so while it may be part of the problem I think there's a bigger culprit (I'm really hoping it's the gasket).

I'm looking back through replies--one other question was Did the pellets burn back during shutdown? And the answer is mostly yes. Every time I've had the six blink error the burn area has been empty and the pellets burned up completely. However, this morning (after running in stove temperature mode for an unknown amount of time) the pellets were mostly burned up, but there was one single partially burned pellet and there were three or four unburned pellets right at the end of the auger. It may have given one last turn at the very end of the burn and the fresh pellets just didn't catch. But that has never happened before and I was experimenting with the new setting.

 

[Bioburner]

Its perfectly fine to solder the connectors. Very easy. Really should have been done in the first place to really complete the expensive quality of stove.
Good luck on gaskets holding the air back the way they should. Have a warm night.
Can make your own tester for a one time use. Several on youtube.

 

[camotan]

New door gasket is installed and I think it passes the dollar bill test. The latch side had a lot more cling, but it was still fairly tight on the other three sides and at the corners. I lit the stove in manual mode, room temperature mode, feed 4, temperature ~=60. It seemed to take but was a small flame--my experience has been for the flame to start out pretty small for five or ten minutes and then take off. But I had to run so I left and by the time I came back the flame had burned out, the pellets were partially burned, and there was no blinking light--status light was just off even though the stove was still at the same settings.

I lit it again and got a better flame going. I did the test with ice water on the temperature probe and it kicked into high gear and the distribution blower came on in a few minutes. I took the probe out of the ice and warmed it with my hands and the distribution blower cut out almost immediately.

I now have the stove in manual mode, room temperature mode, feed 4, temperature ~=70 and it appears to be doing its maintenance burn. Yesterday I had it in a similar setting doing a maintenance burn and it went out after about 6 hours. I've replaced the gasket though, so I guess we'll see.

 

[skipp025atyahoo]

Hi, I've been having difficulty with my Harman P43. It's my primary heater and I run it on manual, feed setting 4, with the room temperature dial set around 65--75 (I turn it down when I leave the house and up at night once I'm home). I don't use automatic ignition.

Starting about a week ago the stove has been burning out while unattended (over the night or while I'm out of the house). The status light gives a six blink error each time, indicating poor or incomplete combustion. I am not out of fuel in this situation.

I keep the stove clean: The burn pot is scraped until it's smooth and all the holes are unblocked; the big ash pan is emptied regularly; the outside air intake is unobstructed and not frosted over; the combustion blower is clean; the flue is clean and I am careful of the ESP probe when cleaning the flue; the fines box is empty and the little air channel behind the fines box is clear best as I can tell; the fines box cover is replaced and the wing nuts tightened firmly; the "v" shaped part at the top of the interior is clear of ash; the auger is clear of pellet dust. I even took the ESP probe out and gave that a clean too, although it only had a thin layer of soot on it.

I've tried kicking the feed setting up to 5, 6, and then 7 and I still have the same problem. Today I was home and able to monitor the stove. I lit a fire and let it do its thing. It kicked up to full, the flame appeared healthy, and the distribution blower kicked in for an hour or two. When the room got up to temperature, the stove dropped to a low setting and eventually went out, even though it's on manual. At that point it had a six blink error. I quickly checked the air intake clapper, but it was not obstructed. And of course, I was not out of fuel.

I have read some forum posts here of a similar situation and the advice was to replace the ESP sensor. While that may be the case, just yesterday I was holding the sensor in my hands. It's a few years old but it didn't seem damaged. I didn't hit it while cleaning the flue, and I'm really curious how it could be broken. It's just a simple thermocouple with some wires, right? Do they wear out? How often does that happen?

I'm prepared to go buy another one, as at this point I don't see what else it could be, but it does seem weird that it would go bad. It would also be annoying to drop $70 and find it was something else.

Just a few minutes ago, I read that the gaskets can be a problem. I checked the gaskets around the door and around the hopper lid. The hopper lid gaskets were a little dusty, so I cleaned them. The door gasket may be bad: it was quite flat. What's more, is that there have been times in the past where a little bit of windex has dribbled down to the lower gasket and there was one time this past week when the stove burned out but the air intake fan was still blowing where frost had literally formed on the bottom of the door. So the door gasket may have some faults. I'm going to buy a new one and in the meanwhile, I picked at it with needle nosed pliers to fluff it up a bit. This shook out a lot of deposits caked into the rope, and by the time I was done it was pretty fluffy and the door needed a fair bit of pressure to close and lock.

I currently have my toyo set around 75 degrees and the P43 active and set to 65 (manual, feed rate 7). My thinking is that the stove has been failing on its low setting when the room is warm, so I want to try keeping the room warm and see if the P43 can maintain it's low burn for the rest of the day now that I've fluffed the door gasket.

If that doesn't work, I guess the next step is to buy that ESP probe? I was hoping there was something else I'm missing. Thanks for any advice you've got, it would be much appreciated because I am near the end of my rope on this problem.

Edit: I forgot to mention that each time I have gotten the six blink error, the burn pot was empty. That is, there were no partially burned pellets, they all burned up and the stove had shut down.

Hello back,

You probably have at least one one of three problems happening. You can help solve your own problem with some
observations. But I will say that I suspect your ESP is probably bad and it would be the first thing I'd replace.

What you want to note is if the auger and combustion blower run as normal before the stove runs out of pellets. And
the important observation based on how my Accentra Insert behaves... as the stove ramps down and runs itself out
of pellets, does the auger still occassionaly feed a smaller amount of pellets in? This action would be compared to
the normal stove turn off cycle down where my Accentra doesn't immediately completely stop feeding pellets in, but
rather ramps down the amount with smaller or wider spaced feed intervals. If this is what you experience, replace
your ESP.

It would be important to note if the Feed LED lights (if your stove has one) and your feed auger motor runs at the
same time. The difference being if the indicator LED lights but the auger motor doesn't run.l If your stove completely
stops feeding pellets, you should look toward the auger operation and it's interlock (association) with the hopper
lid and the pressure sensor. The presence of the LED with the ability to hear/determine if the feed auger motor
(or equivalent for your specific stove model) along with the stove yes/no feeding pellets as it starves down, will tell
you where the problem lies.

cheers,

skipp

skipp025 at yahoo dot com

 

[skipp025atyahoo]

There are many here much better at trouble shooting and explaining the facts but I will offer up some with your question of what makes the ESP break. They don't necessarily 'break' but more likely wear out or possibly something melts inside. I don't know and would say there's no rebuild kit. LOL! The probe goes thru heat extremes. That's its job. To sense and tell the unit what the hot exhaust is doing so the unit can adjust to keep within a certain temp or make adjustments to get there. Kinda like the eyes and ears or feel for the brain (CB control or circuit board) in a sense.

I had to replace a thermistor probe on my Woodmaster last season. Quick and easy like the ESP probe would be. It is or does basically the same thing as the Harman's ESP probe but instead of measuring the exhaust temp it senses the water jacket temp. It could no longer function correctly and send the right info to the control board so the unit could make itself run right and kick off and on or call for heat to bring the water temp up. Some what like a thermostat telling he furnace to kick off and on.

When I pulled it out it looked just like the new replacement and no visible signs of wear nor anything broken. It was broken though and malfunctioning. Put the new one in and it was back to normal. That thermistor probe was similar looking to the ESP probe but different in size and runs off of a typical speaker type wire whereas the ESP has a smaller gauge wire. The probe for the Woodmaster was $22 if I recall correctly and was a bit bigger diameter and length than the ESP probe in the Harman exhaust. I can't see where the Harman probes are three times as expensive but they have you over a barrel so to speak unless you are an electronics guru and could match it up with a cross reference. They are specific to each unit, make, model etc; and you need the correct one set to read within the require parameters and such.

BTW, Welcome! You'll fit in just fine around here.

Hello again to everyone,

In regards to what fails inside the ESP (probe)... depends on what type of probe it actually is. We might
actually call the ESP a thermocouple of some type currently unknown to us.

Before I go forward, let me say that repeated thermal cycling through certain temperature levels or ranges
can and often does modify the lifespan of many thermocouples. Based on my experience, because of the
temperature range the ESP operates through, I'm not surprised that fatigues and fails after a reasonable amount
of use (cycling up an down).

As an example, most older incandescent light bulbs seem to fail at turn on because of the stress experienced
as the filament transitions from the ambient temperature up to its nominal operating value. The transition through
a specific narrow temperature segment is the killer. One reason why a filament light bulb forever left on, can
continually operate many more hours than one turned off and on daily. Repeated transitions through the mentioned
temp segment cause stress and eventual damage/failure. I forgot what that temp range is, but could go look
up the generic label for it if someone had to know... or you could do the research yourself.

The ESP can be many types of thermocouples (or similar device), the best way to determine what it is would
be for a person with a bit of experience working with these type of devices to actually try to test and measure
(a good) one. I have an intermittent one here I'll try to test and measure later in the week. It could be
any one of a number of different type thermocouples, like a semiconductor (diode), resistive, dissimilar metal
or even micro mechanical (I doubt the micro-mechanical one).

In the real world... expect your ESP to fail after a reasonable number of temperature cycles, possibly failing
more often with repeated cold to full on temperature transitions versus having the stove on but throttled back
in temp (but still with an active flame. Depending on the shear number of complete stove temperature cycles, your
ESP lifespan will hopefully live for a number of years. My first one made 5 years of winter time daily on-off
operation before it became intermittent.

cheers,

skipp

skipp025 at yahoo dot com

 

[camotan]

Thanks for the explanation and the info on the ESP. Based on your advice, other comments here, and what I've been reading so far I went ahead and bought a new ESP today (was $50--a bit cheaper than I thought). Just finished swapping it out.

I did my test last night like I wrote and it went out very quickly, after I went to bed (maybe it burned for an hour or so).

I've lit the stove and am headed out again and am hoping it is lit when I return later tonight.

Just wanted to say thanks, and respond that yes, auger and combustion motor and distribution blower do run when their lights are lit. I've been monitoring that and can hear that the three motors make very distinct sounds. I think I have a feel for what "normal" operation is for each and haven't really detected a problem with them. They're like the muscles, and the control board's the brain, with the temperature probe and the ESP the eyes and ears, right? The auger appears to work fine and will indeed feed pellets as needed--and if I turn the heat way up it'll ramp the stove into a nice cheery burn. Only problem is that when the room is warm, it drops back into a maintenance burn and has been going out and producing the six blink error.

Hello back,

You probably have at least one one of three problems happening...

 

[camotan]

Happy to report that after replacing the ESP, the p43 has just passed a 24 hour maintenance burn and has resumed its duties.

 

[Bioburner]

Happy New Year on reliable heating. You sent some ugly cold down to the lower 48

 

[skipp025atyahoo]

Happy to report that after replacing the ESP, the p43 has just passed a 24 hour maintenance burn and has resumed its duties.

Wonderful news...

Also regarding your comment about paying $50 for the ESP (probe). In reality it is probably just some type
of thermocouple I have yet to sit down and figure out (but I probably will). A bare thermocouple can actually be
ordered from a few different companies, but you have to know exactly what type of thermocouple you have,
and then there's the issue of the special, specific ESP holder or mount and the electrical connector.

So there are many cases where it's just more practical and efficient to order the original
part... and then when installed and tested working, move on with the next part of your life.

Best Wishes as we wind down 2014

Regards,

skipp

Skipp025 at yahoo dot com

 

[camotan]

Just wanted to leave a troubleshooting note for posterity since these threads seem to come up in searches:

Definitely try fresh pellets before replacing the ESP. It'll only cost a few bucks and you will likely be able to save your old pellets by mixing them with fresh.

A week or two after I replaced the ESP I had the same problem I've been having all along--as described above. I bought a few individual bags of pellets from a different brand and that solved the problem.

I suspect that the ESP was on its way out, as replacing it did seem to help, but the pellets appear to also be an issue.

I started burning 100% fresh pellets, then kicked the mixture back gradually until I was maybe doing 90% old/10% fresh. Now I'm running on 100% old again and haven't had any more problems. I suspect I just had a pocket of bad bags.

So yeah, do the $5 repair before you do the $50 repair and see where it gets you, and don't worry about wasting your supply as you can still salvage it.

 

[ttdberg]

Well, you have a spare ESP on hand if you ever need one. Glad you worked it out in the end, and thanks for posting the final result.

 

[skipp025atyahoo]

Hi, I've been having difficulty with my Harman P43. It's my primary heater and I run it on manual, feed setting 4, with the room temperature dial set around 65--75 (I turn it down when I leave the house and up at night once I'm home). I don't use automatic ignition.

Starting about a week ago the stove has been burning out while unattended (over the night or while I'm out of the house). The status light gives a six blink error each time, indicating poor or incomplete combustion. I am not out of fuel in this situation.

I keep the stove clean: The burn pot is scraped until it's smooth and all the holes are unblocked; the big ash pan is emptied regularly; the outside air intake is unobstructed and not frosted over; the combustion blower is clean; the flue is clean and I am careful of the ESP probe when cleaning the flue; the fines box is empty and the little air channel behind the fines box is clear best as I can tell; the fines box cover is replaced and the wing nuts tightened firmly; the "v" shaped part at the top of the interior is clear of ash; the auger is clear of pellet dust. I even took the ESP probe out and gave that a clean too, although it only had a thin layer of soot on it.

I've tried kicking the feed setting up to 5, 6, and then 7 and I still have the same problem. Today I was home and able to monitor the stove. I lit a fire and let it do its thing. It kicked up to full, the flame appeared healthy, and the distribution blower kicked in for an hour or two. When the room got up to temperature, the stove dropped to a low setting and eventually went out, even though it's on manual. At that point it had a six blink error. I quickly checked the air intake clapper, but it was not obstructed. And of course, I was not out of fuel.

I have read some forum posts here of a similar situation and the advice was to replace the ESP sensor. While that may be the case, just yesterday I was holding the sensor in my hands. It's a few years old but it didn't seem damaged. I didn't hit it while cleaning the flue, and I'm really curious how it could be broken. It's just a simple thermocouple with some wires, right? Do they wear out? How often does that happen?

I'm prepared to go buy another one, as at this point I don't see what else it could be, but it does seem weird that it would go bad. It would also be annoying to drop $70 and find it was something else.

Just a few minutes ago, I read that the gaskets can be a problem. I checked the gaskets around the door and around the hopper lid. The hopper lid gaskets were a little dusty, so I cleaned them. The door gasket may be bad: it was quite flat. What's more, is that there have been times in the past where a little bit of windex has dribbled down to the lower gasket and there was one time this past week when the stove burned out but the air intake fan was still blowing where frost had literally formed on the bottom of the door. So the door gasket may have some faults. I'm going to buy a new one and in the meanwhile, I picked at it with needle nosed pliers to fluff it up a bit. This shook out a lot of deposits caked into the rope, and by the time I was done it was pretty fluffy and the door needed a fair bit of pressure to close and lock.

I currently have my toyo set around 75 degrees and the P43 active and set to 65 (manual, feed rate 7). My thinking is that the stove has been failing on its low setting when the room is warm, so I want to try keeping the room warm and see if the P43 can maintain it's low burn for the rest of the day now that I've fluffed the door gasket.

If that doesn't work, I guess the next step is to buy that ESP probe? I was hoping there was something else I'm missing. Thanks for any advice you've got, it would be much appreciated because I am near the end of my rope on this problem.

Edit: I forgot to mention that each time I have gotten the six blink error, the burn pot was empty. That is, there were no partially burned pellets, they all burned up and the stove had shut down.

If your stove doesn't fall under the type I describe in the last part of this post, replace your ESP and
get on with your life. The other conditions that might preempt immediately replacing the ESP is if
you haven't cleaned the stove out well enough and the exhaust pipe (in my case up the chimney) is
fairly restricted... or you have the wrong or sub standard fuel. But the empty bowl (no pellets) suggests
the micro controller (board) software is receiving bad values from the ESP (probe). You just have to
figure out what is causing the ESP to report bad values... defective ESP or problems with the fuel.

While I appreciate the suggestions regarding a leak test using the "dollar bill" and other methods, in
reality most decent stoves do have a bit of leakage and are traditionally set up with code to deal with
those variables. You'd have to have a fairly modest measure of leakage to trip the control loop out of
whack.

Other persons mentioned the ESP doesn't look bad... physical appearance has very little or nothing to
do with it's performance. I still haven't tested one to see if it's a diode, thermocouple or RTD but the nature
of the thermal cycles it makes up to the nominal exhaust temp will eventually wear it out, aka cause it
to fall out of spec. In short, I just assume an ESP in this type of situation has a limited life span, which
I have experienced as a few years of regular cold to full on cyclic operation. A pro-active person will
order and have a extra ESP (probe) around for the eventual replacement.

There's also a mention of the types of fuel causing grief... that might depend a bit more on the design
of a specific stove and the actual program (software) on the stove's micro controller board. I would assume
any reasonable range and quality of pellets would be reasonable, but lower quality pellets will generate a
lot more ash and fines. Our local Tractor Supply has seemingly poor planning and for years would run out
of pellets fairly early in the year. In a fairly deep cold snap, many of us bought and used some of the not
so good Wal Mart pellets and even they work, although they seem almost not worth the effort.

Poor quality and wet/moist pellets can cause grief with the ESP operation. This is where a higher end
stove might have better micro controller software (the program running on the computer board) with the
ability to deal with mixed, sub standard and wet fuel. Although some of the newer stoves do deem to have
an increasingly impressive ability to handle mixed and sub standard fuels... You'll have to figure that out
over time in regards to the specific stove model you have.

Good luck,

cheers,

skipp

skipp025 at yahoo dot com

 

[HarmanManP43]

The esp is Type K thermocouple if anyone is interested. That's what I have read at least.