Help with Harman P68

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luv2bwrm

New Member
Nov 15, 2014
19
Maryland
Last fall we had a Harman P68 installed and loved it. This spring when we were running it sparingly it started to loose flame when we filled it all the way up with pellets. Of course then hot weather started and we then had it serviced the first of September where they found that our fan blades were broke in several pieces ?? they replaced the fan blade and also put in a ESP probe. After that it was a warm week so we left it on Stove Mode at the lowest temp. setting, it seemed to be fine. But then it got colder at night over the weekend so I turned it up to the 5 temp setting and it didn't seem to get warmer. The flame would come up like it should, but then it would gradually cycle down to almost going out, then it would start this over. Last year I watched this stove all through the winter and I never saw it do this. It would always keep a consistent flame level when up on the higher heat settings. I called the owner of the store we purchased it at and he had me watch it for about an hour to see what it was dong. When on the lower setting it seemed to be fine, but when I ask for more heat it started this cycle over and would take about 7 minutes to go thru. Of course he came out on the day it was 60degrees, he watched it and also put the tester on it that showed temp for exhaust etc... He said he saw nothing wrong with it.?? So I've run it all weekend and still feel it is not running like it did this past season and is not heating up to the correct level. Has anyone else had this problem?? I know I"m not imagining this, but don't want to call him back up till I have an idea what the problem is??? Even thought about running up to a store that sells the Harman P68 & have them turn theirs on to see what it does at that setting. Help!!!!
 
So I'm going to go with the first question: are you sure it is in manual (stove mode) and not room temp? it sounds an awful lot like it is cycling to keep a specific temp, not a specific setting (although a 7 minute cycle does seem odd).

I find it hard to believe you have already had to have a fan and ESP replaced already (not that I doubt you, just can't imagine the circumstances that would lead to such needs so early in this stove's life). Do you perform regular cleaning maintenance on the stove, or is all cleaning done by the dealer? How often is it cleaned? Answers to these questions can help the more experienced Harman guru's give you informed answers/suggestions.
 
I have had a P68 for 7 years, 2 or 3 years ago I had a similar problem. Where the pipe exits the house, there is a 30 or 45 degree fitting. On the end of the fitting is course screen. With dampness and ash, the screen was probably 75% plugged up. I cleaned that, end of problem. Now I watch for that to happen.

Tom C.
 
So I'm going to go with the first question: are you sure it is in manual (stove mode) and not room temp? it sounds an awful lot like it is cycling to keep a specific temp, not a specific setting (although a 7 minute cycle does seem odd).

I find it hard to believe you have already had to have a fan and ESP replaced already (not that I doubt you, just can't imagine the circumstances that would lead to such needs so early in this stove's life). Do you perform regular cleaning maintenance on the stove, or is all cleaning done by the dealer? How often is it cleaned? Answers to these questions can help the more experienced Harman guru's give you informed answers/suggestions.

Yes it's in the Stove Mode, feed rate is set between 3 & 4. temp setting is set on 5. We clean it about every week.... week & half depending on the amount of ash produced. We went thru about a ton of pellets every 20-25 days depending on the temp outside. I tried running it in Room temp. mode but with our large 4 story farm house the Stove Mode works best for us to have a consistent heat. I originally called the tech & owner of the store in the Spring when it seemed to be loosing its flame then, but had it serviced/cleaned the first of Sept. that's when the tech showed me the broken pieces of fan blade and he also said he ordered a ESP probe and put it in. (which he did)
I also thought it was very unusual that a stove only going thru one season should have so many problems, since all my research had said the Harman P68 was a work horse which is what I chose in a stove, over some of the others that were more attractive. Hope this helps.
 
Is the ESP a red wire or black wire and what color was the original ESP wire. Try running it in Room temp mode 75 degrees feed rate 4 and tell us what it does.
 
I have had a P68 for 7 years, 2 or 3 years ago I had a similar problem. Where the pipe exits the house, there is a 30 or 45 degree fitting. On the end of the fitting is course screen. With dampness and ash, the screen was probably 75% plugged up. I cleaned that, end of problem. Now I watch for that to happen.

Tom C.

No that's not the problem here, since that was also cleaned out when the tech did his all over service of the Stove a few weeks ago. But all info is appreciated. : ) Thanks
 
Please describe all of your current settings. Stove temp (what # setting) or room temp (what temp setting) and feed rate setting. Is the ESP a red wire or black wire and what color was the original ESP wire.

That I'm not sure about, but I can try to find out. Why, does it make a difference??
 
That I'm not sure about, but I can try to find out. Why, does it make a difference??
It does if he changed it to something different and didn't change the dipswitch setting.
 
X 2 with what bogieb stated. If you know what your stove did last year and it's not now operating the same there is a problem but that is what needs to be figured out. When is the last time it was cleaned and which pellets are you using. Same pellets as last year? What you are saying it's doing is not normal. I am pretty new to this pellet stuff and also have a P68.

Is your ESP probe clean? Have you scraped all of the build up off of your burn pot? Flat screw driver works great. The tool that comes with it does not get all of it. Get all of the carbon build up off and scrape until you see nothing but clean metal. Have you taken a 1/16" drill bit and cleaned the holes out in your burn pot? Push one up in down in all of the holes to remove any build up. Is your exhaust vent clean?

Try shutting it down and cleaning all of this first. There is a plate behind your ash pan at your exhaust blower and fan you should take off and shine a flash light in there to inspect how clean it is. You will see your probe also. Clean it all up and vac it out. Take a paint brush to the fan and ESP probe too. Gently. You could have build up and it's not getting a good temp signal possibly.

This will not take long to do at all and it should be done regularly. Once a month will be fine. I don't care if the dealer and others say it's a Harman and to only clean it after a ton or hardly ever. BS!

Let me put it this way. If you are not then that's a good possibility as to why you are having issues. These units are tanks but they also need some love. Sure you can neglect them more so than other stoves but that too comes with consequences.

Try a good and thorough cleaning first. Also take and loosen the 2 wing nuts on the bottom of the burn pot to lift the small plate off. Your igniter is in there. Reach in with your fingers and pull the ash and crud out of there. You will be surprised at what can accumulate inside there. Do the drill bit hole cleaning first and the other cleaning. Shop vac this stuff out of the stove. Put it back together and let us know if you are still having issues. Set your stove to room temp, feed rate 4, and to about 75 on the temp dial. Igniter to auto. If this doesn't get it back to normal then other things can be explored. Most issues are caused by not regularly cleaning.

Let us know what happens then. By the way did the person who replaced the fan and probe clean everything when he was there? Clean your exhaust also and inspect your OAK (outside air kit) for obstructions. bogieb can tell you all about that!;) You can not always trust what some tech tells you either. Some are excellent while others are clueless.
 
Just saw Harman Lover step in. Let him get you taken care of. He is your best friend right now!
 
That I'm not sure about, but I can try to find out. Why, does it make a difference??

Follow his direction. He asks these specific questions for a reason so he knows what he is dealing with.
 
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Follow his direction. He asks these specific questions for a reason so he knows what he is dealing with.
Doesn't the temp setting have to be above 5 for the fan to work in stove temp mode? Not sure as I don't operate in that mode but fluctuation he is seeing sure sounds like he's operating in room temp mode. Cleaning the stove, ESP and resetting the stove as suggested may help. My Accentra insert is a real workhorse but it does need some TLC. I do all my cleanings myself. That way I know it's been done properly. Not hard and detailed instructions are available.
 
Doesn't the temp setting have to be above 5 for the fan to work in stove temp mode?
If the switch is in manual, yes, the above is true.
 
Think he might have replaced a black wire ESP with red wired unit?
Just trying to do what I usually do...rule out the easy stuff first!
 
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What is the difference between the red and black wired ESP probes. Do they have a different resistance? It's basically a thermistor? ? ? Isn't it? Not to get off track but I'm learning too. I will investigate to see which color I have next time I clean.
 
What is the difference between the red and black wired ESP probes. Do they have a different resistance? It's basically a thermistor? ? ? Isn't it? Not to get off track but I'm learning too. I will investigate to see which color I have next time I clean.
Going by memory here but if I remember correctly the older (Black) model is analog and the new one (Red) is digital or maybe it was lower voltage than black model. I'll check. In any case dip 5 has to be in the UP position for the red probe, DOWN for black.
 
What is the difference between the red and black wired ESP probes. Do they have a different resistance? It's basically a thermistor? ? ? Isn't it? Not to get off track but I'm learning too. I will investigate to see which color I have next time I clean.
Oh yeah - if you have an older unit w/o dips you can only use the black'wired unit unless you replace the cb.
 
Well my 2013 P61 ( little brother to the P68 but works the same way) running in Stove temp mode and if you want larger ramp ups of flame and convection fan in lower settings you have to have the Igniter switch in auto. I am told this is the later design. Good luck getting any heat out of Stove Temp manual, it's more of an ambiance thing in manual.. So if you are not in Stove Temp Auto then try that.
 
Well my 2013 P61 ( little brother to the P68 but works the same way) running in Stove temp mode and if you want larger ramp ups of flame and convection fan in lower settings you have to have the Igniter switch in auto. I am told this is the later design. Good luck getting any heat out of Stove Temp manual, it's more of an ambiance thing in manual.. So if you are not in Stove Temp Auto then try that.
What he said!;ex
 
Yes and Yes.... lol it has had a lot of Love & pampering! The tech did clean it inside and out. We normally clean it about every week and half depending on how much ash we're getting. My husband does remove the plate & has gotten behind the Ash pan where the fan & blower are to clean. Since that part was what had broke, he thought it was a good idea to check that area any way thru out the season. Thanks for that info.though.
I know it's hard to describe with out sounding crazy, but I watched this stove burn all last season and it's not performing like it did. But w/o their diagnostic tool saying somethings wrong, all I have is a stove burning pellets and not working correctly.
The problem I see from last year is this cycle of going down to almost no flame, then coming back up. I remember it just burning consistently at a medium to high flame on the 5or6 setting this past season. Which to me would be correct to keep the stove temp mode at a certain consistent temp. Also, the pellets don't seem to feed at a steady consistent basis either, compared to last season.

OK, so I just sat and watched it for about 35 minutes go thru 3 cycles of this up and down flame height which lasted around 10-11 minutes each time. So let me try to describe it as I have seen it:
As the cycle begins, starting from the lowest flame, which goes down to about the bottom of my last ornamental log (2or3inches in height) it then starts feeding pellets inconsistently for about 30seconds, then stops for 30 seconds, then feeds again for 30seconds..... it continues this up to about the 5minute mark where it then stops feeding pellets. The flame has continued to grow from the start of this cycle and continues till about approx 8 or 9minutes into it, where the flame then starts to decrease till about the 11 minute mark where this cycle will start over again once the flame is down to about 2 or 3inches again. (No pellets feed after the first initial 4or 5 minutes, they only start back feeding when this same 11 minutes cycle starts over again once the flame has diminished.)
What do you all think??
 
Yes and Yes.... lol it has had a lot of Love & pampering! The tech did clean it inside and out. We normally clean it about every week and half depending on how much ash we're getting. My husband does remove the plate & has gotten behind the Ash pan where the fan & blower are to clean. Since that part was what had broke, he thought it was a good idea to check that area any way thru out the season. Thanks for that info.though.
I know it's hard to describe with out sounding crazy, but I watched this stove burn all last season and it's not performing like it did. But w/o their diagnostic tool saying somethings wrong, all I have is a stove burning pellets and not working correctly.
The problem I see from last year is this cycle of going down to almost no flame, then coming back up. I remember it just burning consistently at a medium to high flame on the 5or6 setting this past season. Which to me would be correct to keep the stove temp mode at a certain consistent temp. Also, the pellets don't seem to feed at a steady consistent basis either, compared to last season.

OK, so I just sat and watched it for about 35 minutes go thru 3 cycles of this up and down flame height which lasted around 10-11 minutes each time. So let me try to describe it as I have seen it:
As the cycle begins, starting from the lowest flame, which goes down to about the bottom of my last ornamental log (2or3inches in height) it then starts feeding pellets inconsistently for about 30seconds, then stops for 30 seconds, then feeds again for 30seconds..... it continues this up to about the 5minute mark where it then stops feeding pellets. The flame has continued to grow from the start of this cycle and continues till about approx 8 or 9minutes into it, where the flame then starts to decrease till about the 11 minute mark where this cycle will start over again once the flame is down to about 2 or 3inches again. (No pellets feed after the first initial 4or 5 minutes, they only start back feeding when this same 11 minutes cycle starts over again once the flame has diminished.)
What do you all think??
ps......it's in Stove Mode and Auto
 
ps......it's in Stove Mode and Auto
Depending on your settings (Please share them all) it sounds like either a dirty ESP or an improper ESP dip switch setting. BTW what do you mean about feeding pellets "inconsistently?" What pellets are you using?
 
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