Harman P68 Distribution Fan ESP concerns

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MikeSJ I was planning on ordering a backup ESP since they appear to be the weak link in so many problems. I purchased this one at Mountain View hearth products. Do you or anyone else have a different vendor to purchase a backup ESP from?[/QUOTE]

I'm sorry- I don't know any vendors other than my local stove shop.

I really do think that once you get this esp thing figured out you will be thrilled with this stove.
 
MikeSJ I was planning on ordering a backup ESP since they appear to be the weak link in so many problems. I purchased this one at Mountain View hearth products. Do you or anyone else have a different vendor to purchase a backup ESP from?

I'm sorry- I don't know any vendors other than my local stove shop.

I really do think that once you get this esp thing figured out you will be thrilled with this stove.[/QUOTE]
Having ordered a Red Wired ESP today with a three business day delivery I'm hoping that by next Tuesday or Wednesday with the Red Wire Updgrade and changing Dip Switch 5 to ON that my P68 runs as it should. So many disappointments so far that I will try to remain optomistic but that AIN'T easy. I appreciate everyone who has contributed to this thread with their experiences and knowledge.
 
OK folks here is some more bad news. The new RED Wired ESP fit the hole just fine and installed easily after all my practice with the black wired ESP. I flipped the DIP Switch #5 to the ON position as indicated for the RED wired ESP and then plugged the unit in with the lower right knob in the OFF position with feed rate set at 4, not TEST. The temperature knob was set at the #5 or about 75 degrees. The combustion and distribution fan immediately started running and in about 8 seconds the status light gave the 3 Blink ESP error. Ugggg, no, no no, it's supposed to work now. With the NEW Black Wired ESP #5 OFF, the power light came on with what sounded like a quick fan test and then nothing happened until I turn the feed knob to TEST which fired up the Distribution Fan, the Combustion Fan, the feeder for about 40 seconds and I think the ignition light for a moment. Once I took it out of TEST mode and put it in Room Temp mode with a fan speed set close to the L, not the H it would go through the start up process just fine. Once the fire was started nicely, the probe sensed the heat the "ignition" light turned off and it would start running normally for a minute or two and then it would throw the 3 Blink error. It did this in Room Temp or Stove Temp mode in Auto Ignition or Manual. No settings with the NEW black wired ESP would not throw the 3 Blink error after a little while. I let the stove run for several hours with the three blink error being displayed and the only thing the stove would do is keep the flame low and cycle the Distribution Fan from low to high every few minutes continuously. With the NEW Red Wired ESP installed and the Dip Switch Set to ON when plugged in both the Combustion and Distribution Fans started running immediately and a few seconds later threw the 3 Blink error as I said above. Help/Help/Help.............. Close to pulling out my hair after waiting and paying for 2 and 3 day deliveries for the ESPs. Are there a set of dip switch settings I need to try beside the 1&2 - ON, 3&4 - OFF, 5,6,7&8 - ON ??? My 2008 P68 has the 4 RPM feed auger motor. Anxiously awaiting a reponse.
 
Make sure that the connector on the sensor which is esp connect to the control card is connect in the right direction if the temperature information that is sent to the processor has the opposite and gives information that the probe is in esp apart from its range of temperature
 
it is not for nothing that the two strand of thread of the probe esp there is one that is coded red white and the other is red
 
If the connection of the esp probe is connected you can remove the electronic card and check if there is no weld crack on the electronic board.
I think when you turn on your stove until the igniter is one processor does not check the temperature of the probe since the stove begins to turn but the ignition cycle after the igniter will turn off and at this time the safety esp becomes the probe and if the contact is not good or welding to break the processor receives a temperature off range and stops on 3 flashes
 
If the connection of the esp probe is connected you can remove the electronic card and check if there is no weld crack on the electronic board.
I think when you turn on your stove until the igniter is one processor does not check the temperature of the probe since the stove begins to turn but the ignition cycle after the igniter will turn off and at this time the safety esp becomes the probe and if the contact is not good or welding to break the processor receives a temperature off range and stops on 3 flashes
I have closely looked at the circuit board on both sides and can't notice anything that looks abnormal. I reset all the connections for the wire harness, the room sensor and the EXP. Those are the only connections to the circuit board that are user moveable. I would like someone to see if I have all the Dip Switches set correctly based on my newer circuit board, the Red Wired ESP, the 4 RPM feed motor and my altitude of 6400 feet above sea level where the stove is supposed to function.
 
for the motor rpm 4 I do not think that's your trouble the only thing that can happen is that your stove can give less btu
 
did you try to disconnect your ambient temperature probe and try to light the stove in automatic temperature stove to see if there are still 3 flashes
 
did you try to disconnect your ambient temperature probe and try to light the stove in automatic temperature stove to see if there are still 3 flashes
Just tried that and it works the same with both the Distribution and Combustion Fan running and then the 3 blink error code showing. I am leaning toward the fact I either have the dip switches on my circuit board set incorrectly or the circuit board is bad and needs to be replaced.
 
Just tried that and it works the same with both the Distribution and Combustion Fan running and then the 3 blink error code showing. I am leaning toward the fact I either have the dip switches on my circuit board set incorrectly or the circuit board is bad and needs to be replaced.
I'm leaning towards a bad board but must admit, doing so as I rub my chin whiskers.
 
verify tester for outlets and checks for polarity, grounding
 
I'm leaning towards a bad board but must admit, doing so as I rub my chin whiskers.
Yours and my chin whiskers are getting a work out and after I saw what happened when I installed the New Red Wired ESP, set Dip Switch #5 to on and plugged it in I was starting that process with a smile, and when both fans came on immediately and then the 3 Blink monster attacked I wanted to scream out Houston, "We Have a Problem".
 
If you want to try unplugging the distribution motor and try to turn on your automatic stove for when the igniter going out if you still have the problem.
maybe the distribution fan takes too much current to and causes this trouble
 
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Your dip switches are set correctly according to the PDF that BioBurner provided. Maybe try blowing the circuit board with a can of compressed air? I would hate to see you have to buy a new board

$210 is the cheapest I've found so far:
http://nevelsstoves.com/1-00-05886-harman-control-board.html
miteclipse, I did that early on in this diagnostic process. The board is very clean and all the connectors were "reseated". Unless someone can suggest something else I think I'm going to order a NEW Circuit Board later today or tomorrow. It won't be long and my great purchase of a used Harman for a really good price will be like..............Damn, I should have bought a new one with the warranty. After the circuit board purchase I will still be nicely ahead of the game, but if I have to change out the auger and motor along with any of the fans................I didn't do well. Even at the young age of 70 I guess we can all learn lessons of life. (<:
 
miteclipse, I did that early on in this diagnostic process. The board is very clean and all the connectors were "reseated". Unless someone can suggest something else I think I'm going to order a NEW Circuit Board later today or tomorrow. It won't be long and my great purchase of a used Harman for a really good price will be like..............Damn, I should have bought a new one with the warranty. After the circuit board purchase I will still be nicely ahead of the game, but if I have to change out the auger and motor along with any of the fans................I didn't do well. Even at the young age of 70 I guess we can all learn lessons of life. (<:
I just checked your link for the new Circuit Board and they are OUT OF STOCK.
 
I did that with both the Black Wired and Red Wired ESP as I was trying to remove every possible variable I had control of.
If you pop out the board, unplug the red wires and just plug in the black, flip the dip switches I wonder if Now The Black Wired sensor will do the same as the red is doing. Not install the black but just plug it back in. With all the pulling of wires etc and if something is loose in the board it might. Just a method of proofing .
 
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did you try what I mentioned in the post 69
 
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