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.
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.
Last edited:
Couple dabs of solder and was good to go.
