Harman P68 weak performance.

[Taylor Mahaffey]

Hello, new member here.

This is my third year with my Harman P68. The last two seasons, if I set the stove to STOVE TEMP and 7, the fire would get so big that it was almost scary. It would stay that way until you turned it down, or off. In ROOM TEMP, if you set at 90 degrees, it would get the house to that temperature in no time.

This year is different.

It seems to have nothing but a small maintenance burn all the time. At start up, the fire is big and glorious, but after that it just burns down to a small flame. I can have it set at 90 degrees and my small home will gain about 5 degrees in an hour or so. I have the feed setting all the way up, and the embers never get anywhere near the edge. It is almost as if the stove THINKS it is burning well, but isn't. I am getting no error blinks or anything.

I have cleaned EVERYTHING really well as I do every year, however Im guessing I may have damaged the ESP probe in the exhaust, causing it to read hotter than it actually is, therefore causing the stove to not burn at full capacity. Before I go buy a $100 exhaust probe, or pay someone $100 to plug the HARMAN METER in to it, I wanted some expert views on if this is the likely scenario.

Any help would be fantastic.

Regards,
NEWBIE

 

[Enigma869]

I'm not mechanically inclined but I found a comment my Harman service guy made yesterday rather interesting. He told me that it was VERY important not to drop anything down the space between the hopper and the top of the stove. Of course, no sooner did he say that and sure as hell, I dropped a single pellet down there last night. This stove is a lot tougher to fill than my Accentra insert (which never got hot on top), so these things are going to inevitably happen. Anyway, he told me that he gets stories exactly like the one you're telling all the time, and when he gets to the house, he usually finds a pellet or three interfering with the operation of the stove, that slipped down that space. Again, I'm not a service tech, so I can't really articulate what the precise problem is. I will say that if dropping a pellet or two down that space is that catastrophic for the stove, Harman should seriously re-consider their design, and eliminate that space! I did just buy a coal hod to hold my bag of pellets and hope it makes loading a bit easier, with no over spill in places that pellets shouldn't be. Hopefully, someone else can chime in with some other ideas on what you're experiencing and how to fix it. Good luck.


John

 

[Taylor Mahaffey]

I'm not mechanically inclined but I found a comment my Harman service guy made yesterday rather interesting. He told me that it was VERY important not to drop anything down the space between the hopper and the top of the stove. Of course, no sooner did he say that and sure as hell, I dropped a single pellet down there last night. This stove is a lot tougher to fill than my Accentra insert (which never got hot on top), so these things are going to inevitably happen. Anyway, he told me that he gets stories exactly like the one you're telling all the time, and when he gets to the house, he usually finds a pellet or three interfering with the operation of the stove, that slipped down that space. Again, I'm not a service tech, so I can't really articulate what the precise problem is. I will say that if dropping a pellet or two down that space is that catastrophic for the stove, Harman should seriously re-consider their design, and eliminate that space! I did just buy a coal hod to hold my bag of pellets and hope it makes loading a bit easier, with no over spill in places that pellets shouldn't be. Hopefully, someone else can chime in with some other ideas on what you're experiencing and how to fix it. Good luck.


John

Excellent. Thanks for the post. Just took all the panels off, checked everything. No lodged pellets, pet hair, or anything else I can see. I also took the ESP out, cleaned it off really well and inspected for damage.

Plugged it back in and it seems to be running pretty good for now! I'll keep you posted.

Hopefully a little soot on the ESP didn't cause all this headache!

 

[P38X2]

I've dumped likely 1000's of pellets, a few at a time, between the hopper and firebox in my years burning pellets in P series Harmans. Never had an issue with the exception of needing pull the shop vac out. If a pellet was to somehow ricochet and lodge itself into the dist blower, auger motor linkage or combustion motor, you'd likely know it immediately.

You said you cleaned your ESP and the problem went away. The fact you said you actually removed it makes me think its a loose/pinched wire. How much is "a little soot"?

 

[stayfitz]

Have you changed your pellet brand from last year to this year? My P68 required adjustment from the Blazers (last year) to Golden Fire (this year). I had to turn down the feed rate control from approximately 3.4 to just under 2.9! And I'm producing more heat! Also, check your room temp thermistor. I purchased (3) Harman replacements. My dog eat the first one included with the stove. All (3) replacement thermistors have slightly different resistance profiles. As a result, the room temp dial setting/number will have an offset of 2 to 5 degrees. I recently extended the length of the thermistor cable in use this year. The current placement allows for a better room read and the additional length helped "zero" the offset. Sorry... rather long winded, but maybe you should check your thermistor cable, connection, placement, etc as well?

 

[Taylor Mahaffey]

I've dumped likely 1000's of pellets, a few at a time, between the hopper and firebox in my years burning pellets in P series Harmans. Never had an issue with the exception of needing pull the shop vac out. If a pellet was to somehow ricochet and lodge itself into the dist blower, auger motor linkage or combustion motor, you'd likely know it immediately.

You said you cleaned your ESP and the problem went away. The fact you said you actually removed it makes me think its a loose/pinched wire. How much is "a little soot"?

Well its hard to explain a little soot. It seemed like it was probably the same amount that gets stuck on the glass if you don't clean it in some time. I would think if one of the wires was pinched or a loose connection, that the stove would throw an error code if something was terribly wrong. The stove ran before I cleaned it, just at a very low output. Now its a champ like day one…

 

[Taylor Mahaffey]

Have you changed your pellet brand from last year to this year? My P68 required adjustment from the Blazers (last year) to Golden Fire (this year). I had to turn down the feed rate control from approximately 3.4 to just under 2.9! And I'm producing more heat! Also, check your room temp thermistor. I purchased (3) Harman replacements. My dog eat the first one included with the stove. All (3) replacement thermistors have slightly different resistance profiles. As a result, the room temp dial setting/number will have an offset of 2 to 5 degrees. I recently extended the length of the thermistor cable in use this year. The current placement allows for a better room read and the additional length helped "zero" the offset. Sorry... rather long winded, but maybe you should check your thermistor cable, connection, placement, etc as well?

I am burning the same pellets. It was really horrible though, and I ruled out any problematic pellets. I have seen changes in feed rate, smoke, and soot buildup inside the stove with changes of pellets. I have never seen pellets cause a stove to operate horribly like my P68 was doing. I think for now I fixed the issue, but who knows if a crimped wire or something like that will bring the problem back...

 

[Bioburner]

Possibly a loose connection of the room temp probe. Its on the list of possible poor stove performance.

 

[P38X2]

Well its hard to explain a little soot. It seemed like it was probably the same amount that gets stuck on the glass if you don't clean it in some time. I would think if one of the wires was pinched or a loose connection, that the stove would throw an error code if something was terribly wrong. The stove ran before I cleaned it, just at a very low output. Now its a champ like day one…

Wouldn't think that amount of stuff on the ESP would cause an issue, but I suppose it's possible. As others suggested, check the room probe connection.

 

[Taylor Mahaffey]

Wouldn't think that amount of stuff on the ESP would cause an issue, but I suppose it's possible. As others suggested, check the room probe connection.

Will do. Thanks.