Brand New Harman P43 question

Harman Lover 007

Minister of Fire
I don't usually ask the questions here because I feel I have a pretty good knowledge of the product but.....I talked a friend into buying a Harman P43 which he has installed in his basement. With the stove running Room Temp auto set at 65 degrees the stove runs until the set temp is satisfied and shuts down. It won't, however, restart without turning the pot to OFF and then back to 65 deg. He extended the room sensing probe (on my advice) about 20 feet from the stove to get more even heat to the entire basement. The set temp is definitely being reached. No status light flash. Just Power light on. I'm going to test the temp probe with my multi meter. What is the resistance I should be looking for? Any thoughts on what it might be?
 

Harman Lover 007

Minister of Fire
Bumping this back up to the top in the hopes that I can get a fresh look. More to add to the original problem. I told him to try running the stove in Stove Temp Auto (now it's called Constant Burn) and see what happens. The stove runs for several hours at the set temp and then shuts down. Hopper still has pellets and no status light blink codes. Turn it off and then back on and it fires right up. This is a strange one.....
The stove is brand new so he's going to call the dealer today and see if they have any ideas.
 

jp99

Burning Hunk
Jan 7, 2015
142
Ohio
What's in the burn pot when it shuts down? Is there unburned pellets, or just ash?
 

Harman Lover 007

Minister of Fire

jp99

Burning Hunk
Jan 7, 2015
142
Ohio
I agree, strange behavior. In stove temp mode and automatic for the igniter, that stove should run until the fuel is exhausted. I almost wonder if the vacuum switch is operating abnormally (I had similar behavior with my PC45 when it was new, and it was traced down the an intermittent problem with the vacuum switch; replaced the switch and it has been fine in the seven years since then). The switch can be shorted out to test that and if the problem stops then the switch is the issue. Or since the stove is new he could ask the dealer to replace the switch without the test.

Has he had any response from the dealer about possible causes?
 

F4jock

Minister of Fire
Nov 12, 2014
1,603
Red Rock, PA
Sounds like a board. My guess is that there is no restart command after a powered shutdown. When you cycle to off and back on it's a start sequence after what amounts to a reset. Since it runs and feeds for hours gotta assume all permissives are satisfied and I'm assuming not enough run time to have ash be a factor?

If you want to play with the temp probe use the ice cube trick when it's shut down but since it's shutting down you have to think that the temp probe is opening when satisfied and since it runs you might assume it stays closed until it is satisfied . . . . thus it probably is working.

Should be warranty on a new stove.
 
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Harman Lover 007

Minister of Fire
Dealer is stumped too. Not offering too many suggestions. We shortened the temp probe back to stock length but that doesn't explain shut down in constant burn mode.....
 

F4jock

Minister of Fire
Nov 12, 2014
1,603
Red Rock, PA
OK I didn't see that one. You said Stove Temp Auto. My Harman is operated that way and does a complete shutdown necessitating a full-blown auto-restart including igniter and initial pellet feed timing. If room temperature probe is satisfied for about a minute the stove shuts down until I get about a two degree temp drop. Then it restarts as above. Been doing that for most of the now eight season I've had it.

To me, constant burn would be Stove Temp Manual not Auto! In that case it goes into a maintenance burn when temperature is satisfied and never shuts down. Unless Harman has changed the control algorithm there is no way Room / Auto is a constant burn.
 
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Harman Lover 007

Minister of Fire
It shuts down in both Stove Temp/Constant Burn/auto (without running out of pellets) and room temp auto.
 

F4jock

Minister of Fire
Nov 12, 2014
1,603
Red Rock, PA
It shuts down in both Stove Temp/Constant Burn/auto (without running out of pellets) and room temp auto.
Did you try the ice cube on the probe trick in Auto / Room Temp to see if it restarts?

If it shuts down in stove temp AND in Room Temp Manual after running for hours I'd still say board.
 
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alternativeheat

Minister of Fire
Dec 19, 2013
3,797
Cape Cod, Ma.
You could just jump out the vacuum switch and see what it does. It's not that it's over firing so worth a try. Brand new stove though, the dealer should be all over it, even if he can't get it to stay going initially. I have to imagine he is in contact with Harman on it.
 

F4jock

Minister of Fire
Nov 12, 2014
1,603
Red Rock, PA
You could just jump out the vacuum switch and see what it does. It's not that it's over firing so worth a try. Brand new stove though, the dealer should be all over it, even if he can't get it to stay going initially. I have to imagine he is in contact with Harman on it.
The key here IMNTBHO is the fact that other runs normally until temp is satisfied, then shuts down and will not restart unless it is cycled off. That tells me that all the permissives are working. I don't know if Lover had tried an ice cube on the probe yet but if that doesn't start it again there can only be two causes. 1) The probe which I doubt because if it wasn't closing the stove would give the blind k signal for bad probe and it apparently opens because the stove shuts down when room temp is satisfied. 2) The board isn't giving a restart signal when the probe closes.

I know it's a new board but all it takes is one cold solder joint . . . . .
 

Harman Lover 007

Minister of Fire
You could just jump out the vacuum switch and see what it does. It's not that it's over firing so worth a try. Brand new stove though, the dealer should be all over it, even if he can't get it to stay going initially. I have to imagine he is in contact with Harman on it.
Yes he is and it's a very reputable dealer here. They are coming out next week. I don't want to mess with it too much since its under warranty. It's working but it's too much babysitting at this point.
 

miteclipse

Member
Mar 8, 2013
159
Hughesville, MD
Set the feed rate to 3. Scrape the ash off the burnpot and relight. Your feed rate is set to high. High ash pellets will burn more which in turn covers the air holes so air can't move. I have seen this before and lowering the feed rate fixed.
 

bogieb

Minister of Fire
Oct 31, 2014
2,765
South Central NH
I'm sure that is quite a disappointment for your friend, not having the stove work correctly straight out of the box. And, such a strange problem. Sorry I have no suggestions, but hope the dealer/Harman can figure this out. Hopefully it is the board, and a straight swap out will cure its ills. If not, then I would suspect a damaged wire somewhere, which will suck to chase (I will be the first to admit I know nothing about electronics and is purely a guess).
 
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alternativeheat

Minister of Fire
Dec 19, 2013
3,797
Cape Cod, Ma.
Set the feed rate to 3. Scrape the ash off the burnpot and relight. Your feed rate is set to high. High ash pellets will burn more which in turn covers the air holes so air can't move. I have seen this before and lowering the feed rate fixed.
On a Harman P43 ? I've had my pot pretty ash bound on my P61 and it kept going. The only miss fire I've had was because I went a little long on cleaning in the chamber where the igniter sits below the burn pot. And then the pot filled with pellets and the stove shut down on time out. Knowing 007 he probably has this guy running a feed rate between 3 and 4, that shouldn't be a problem on a P series stove . It sounds like the symptoms are different anyway.
 

Harman Lover 007

Minister of Fire
On a Harman P43 ? I've had my pot pretty ash bound on my P61 and it kept going. The only miss fire I've had was because I went a little long on cleaning in the chamber where the igniter sits below the burn pot. And then the pot filled with pellets and the stove shut down on time out. Knowing 007 he probably has this guy running a feed rate between 3 and 4, that shouldn't be a problem on a P series stove . It sounds like the symptoms are different anyway.
Correct....this has nothing to do with ash or feed rate....
 

UpStateNY

Feeling the Heat
May 4, 2008
369
Catskill Mountains
While the dealer is trying to resolve the problem, I would try restarting the stove and then switching to manual with a level 2 feed rate just to see if the stove keeps running. The result of that test may provide some other useful information to help find the problem when running AUTO.
 
Mar 29, 2011
7
We just purchased a floor model Harman P-43 and the smoke smell coming from it is overwhelming. When you start it up there is barely any smoke coming out the chimney outside. The smoke smell seems to be coming from the pipe that comes directly out of the stove in the back. When installed and smoke poured out my husband was told give it a week.....this stove was previously used in the stove store.....did the dollar bill test in the door....any suggestions? Installer is supposed to show up tomorrow to check out out. My faith in them is wavering
 

bogieb

Minister of Fire
Oct 31, 2014
2,765
South Central NH
We just purchased a floor model Harman P-43 and the smoke smell coming from it is overwhelming. When you start it up there is barely any smoke coming out the chimney outside. The smoke smell seems to be coming from the pipe that comes directly out of the stove in the back. When installed and smoke poured out my husband was told give it a week.....this stove was previously used in the stove store.....did the dollar bill test in the door....any suggestions? Installer is supposed to show up tomorrow to check out out. My faith in them is wavering
What was the verdict from the installer?
 
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