Harman p38+ circuit baord upgrade kit

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breed5577

New Member
Nov 7, 2014
28
Northern, NJ
Has any one done the Harman p38+ circuit board upgrade. The instructions are ok but I am having trouble figuring out where I ground the dist blower, comb motor and power feed. It appears on the pictures provided that they all attached to the two prong grounding post provided in the hardware kit to the power board clamp plate which is attached to the distribution heat shield. Electrical work is not my strong point. Thanks. Barry
 
Hi Barry,
As a matter of fact... our 7 year old P38 was having auger feed issues yesterday and, to put it frankly, acting real goofy with the various motors randomly cycling. I thought it was a bad batch of pellets at first, but after fighting with it most of the day to keep lit, I knew something else was off. So I made a run to our local dealer and put in the upgrade kit along with a new ESP probe, not knowing if the original probe may be faulty too. The wiring is not explicitly clear (and the pictures are barely legible), but yes, all the green ground wires do connect to that small additional sheet metal U bracket supplied in the kit. A word of caution too, that wiring the feed auger motor with the low level control switch (if I am describing correctly by memory) is a little tricky. The wiring diagram in the kit shows an integral hopper lid switch, which our model did not come with. I ended up wiring as if that switch was not in the loop. Wiring up the main input power, distribution motor and combustion motor into the wiring harness was pretty straight forward. Wiring the auger feed motor and low level switch was not as straight forward. I ended up taking out the original section of wire that ran across the back of the stove for these two devices and wired directly into the new harness. Also I found that the kit did not supply every last, little crimp connector that you will need to do the job complete. Fortunately I had a few spare male/female mating crimp connectors on hand.
Feel free to contact me direct too if you have any further questions.
Best Regards,
Andy
 
Last edited:
Hello Andy
I also installed a new board and probe today. I'm having an issue. The stove runs through the test setting fine but when I turn it to run on stove or room temp, only the stoves combustion motor works and the auger and blower stop. Thus the stove goes out. My new esp is the black wire style so the #5 dip is off. Any suggestions would be greatly appreciated.

Thank you
Maly96
 
Hello Maly96,

I took a quick look at the updated P38 user manual and on page 14, it does list some possible errors that are displayed via status light blinks. Short of seeing if you get any status light errors, I would double check all the wiring per the retrofit kit installation instructions. If that still does not reveal anything further, I would suggest a call to the retail distributor that you purchased the kit from. I would think they should be able to diagnose your symptoms over the phone and be able to help. Not sure where you are located. I am in southwest New Hampshire and our 'local' retail store is located in Whately, Massachusetts. Their name is "The Fire Place" (... go figure... :) - phone number 413.397.3463 They were very helpful for me.

Best Regards,
Andy
 
I also installed a new board and probe today. I'm having an issue.
How are you making out...I have a newer board but have not installed yet and would like to hear if any issues..
 
Andy
Thanks for all your input. Turns out all I needed was a new probe, 1st one was bad.. Weird because it didn't flash the status light. Works like a charm now. The wiring is pretty straight forward.

Gfreek
I checked all the components before installing the board. That way I knew everything was good before i started Don't forget to check the vacuum switch. Easy kit to install. Only took about 2 hours, minus having to install a 2nd new esp. My kit was missing a couple crimp connectors but I had a supply of those on hand. Hope it all works out for you
 
Hi all,

I was also having issues wiring up the auger/vac switch on this new kit for a 97 P38. Does the vacuum switch need to be grounded as well? Curious before I re crimp tonight.