Harman Potentiometers

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crayfish

Member
Oct 10, 2013
8
Hello,
I need both the 50K and 100K trimpots for Harman pellet stove control boards.
I have tried to order from Brunners. They charged my card through Paypal but I never received any parts. I am currently addressing this through Paypal and still have not received any word from Brunners. Does anyone know of an alternative vendor for these trimpots? Ebay doesn't seem to have them any more.
 
This looks to be a serious repair issue for Harman stove owners
 
Hello Crayfish, I had the same problem....needed 100k pots for my Harman P43 control board. I also ordered from Brunners and eventually got a refund from EBay. Called and emailed Brunners numerous times with no response.
I exhausted every avenue trying to find these pots. Harman was no help at all.
I tried at least 8 electronics parts distributors....no luck.
Radio Shack is a joke.
I even emailed a company in Spain that actually makes those pots for Harman. I was supposed to get a few samples sent to me for free. I was very excited. It's a long story and a few emails back and forth.....but I was supposed to be contacted by their distributor here in the States to have them sent to me. I finally get contacted and they wanted to charge me $30.00 per pot plus shipping. Ridiculous! 3 pots and I'm half way to a new complete board.
So......Winter is coming and I need my heat, so I gave up my search and replaced the entire board. All is working fine now.
 
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crayfish said:
Hello,
I need both the 50K and 100K trimpots for Harman pellet stove control boards.

I have tried to order from Brunners. They charged my card through Paypal but I never received any parts. I am currently addressing this through Paypal and still have not received any word from Brunners. Does anyone know of an alternative vendor for these trimpots? Ebay doesn't seem to have them any more.
Click to expand...

I sent a board to them and they replaced the potentiometers this spring. They also checked some other things on the board. By the time it was done I had close to 100.00 in it. It took quite a bit of time to get it back but it worked. I got the impression it was a one man show and he didn't do anything until he had a group of them to do. Having said that there is another outfit that would remove and install new ones. Maybe have to go back through Hearth to find the info or check in E-Bay or Amazon.
 
ACP Technologies (Spain) manufactures the trimpots. They never responded to my emails. I emailed the North American distributors but have not received a response yet.
 
Mouser.com maybe. I wouldnt even know what to look for on their site
 
Just an update: Brunners still hasn't responded to my emails, phone calls or any communication from Paypal so Paypal refunded me the payments I made and closed the case. Unfortunately it looks like he may be out of business.
 
Weird. Their website is still up and appears to be taking orders. They even have a "New Products for November" page.
 
They sell fans and motors too so maybe its just the pots not available. If they continue to not fulfill orders Ebay will act.
 
crayfish said:
Hello,
I need both the 50K and 100K trimpots for Harman pellet stove control boards.
I have tried to order from Brunners. They charged my card through Paypal but I never received any parts. I am currently addressing this through Paypal and still have not received any word from Brunners. Does anyone know of an alternative vendor for these trimpots? Ebay doesn't seem to have them any more.
Click to expand...
Ebay has them now.
 
What type of behavior are the bad pots causing? Is it causing sporadic temperature setting? In room temp mode, I'll turn the control up, and sometimes it doesn't come on...and when we wake up in the middle of the night we are being baked out. I checked the probes...at room temp the ESP probe is 480K and the room temp probe is 3.5K. The fact that I can read some value...would lead me to believe they are functioning. Also, never had un-burnt pellets or flashing lights
 
All kinds of issues related to them. I had one that it would turn itself on even though it was and had been off. Feed control was feeding strange and eventually would not allow to go to test mode are two events I have had.
Semi plugged venting can cause your strange issue too.
Welcome
 
Interesting...I remove the stove every year to do the deluxe cleaning...plus every time the pan fills up I'll do the internal cleaning...inside the combustion chamber...but I'll look into the semi plugged venting anyway. I have removed the control board and I will test the pots as well. I have been looking on Ebay for replacements...no luck yet.
 
thibs23 is the ebay vendor I got three for US $25 last month
 
dfreeman said:
What type of behavior are the bad pots causing? Is it causing sporadic temperature setting? In room temp mode, I'll turn the control up, and sometimes it doesn't come on...and when we wake up in the middle of the night we are being baked out. I checked the probes...at room temp the ESP probe is 480K and the room temp probe is 3.5K. The fact that I can read some value...would lead me to believe they are functioning. Also, never had un-burnt pellets or flashing lights
Click to expand...

The problem I was having was that the stove would fire up even if it was in the off position. It wouldn't shut down again until it ran out of pellets. If the pot was in the "off" position and I would just jiggle the switch, without turning it, the stove would fire up regardless of the room temperature. I never had any flashing lights (error codes) either.
After an exhaustive search, I was unable to locate new potentiometers. I decided to replace the entire control board. Since I replaced the board I have burned approximately 3.5 tons of pellets without any problem at all. I also believe the stove runs better now than when it was new....hard to explain, but the switches have a different feel and I think the stove is more accurate.
 
Sawdust62 said:
The problem I was having was that the stove would fire up even if it was in the off position. It wouldn't shut down again until it ran out of pellets. If the pot was in the "off" position and I would just jiggle the switch, without turning it, the stove would fire up regardless of the room temperature. I never had any flashing lights (error codes) either.
After an exhaustive search, I was unable to locate new potentiometers. I decided to replace the entire control board. Since I replaced the board I have burned approximately 3.5 tons of pellets without any problem at all. I also believe the stove runs better now than when it was new....hard to explain, but the switches have a different feel and I think the stove is more accurate.
Click to expand...
I have noticed differences in three different boards in the same stove. Each board was about 5 years different in age. Seemed each newer version was faster to react to temps.
 
Bioburner said:
I have noticed differences in three different boards in the same stove. Each board was about 5 years different in age. Seemed each newer version was faster to react to temps.
Click to expand...

My stove was purchased new and the pot switch went bad after 3 years. I compared my old board to the replacement and they were identical.
 
Would be hard to tell if the firmware is different. The boards I had were all more than five years apart. Would be nice to know if the Harman diagnostic tool would tell one that info.
 
dfreeman said:
I removed the temperature control pot, soaked it in alcohol, sprayed in a light lubricant, then re-installed. Stove works like a charm now
Click to expand...
Well that's good to hear. Only a couple months of heating season to go so you have time to get in a new set.
 
I have two boards with same p/n just different revs and they even have different value pots in them so best to verify before ordering on ebay.
The seller info on here is also outdated because you can now order 10x longer life pots “ultra long life” from a different seller. I have them in my main board and backup board and controls are much better than the originals
 
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