Harman P68 refuses to shutoff.

[homeskillet]

I have a P68 that i have always run in stove temp mode. This year occasionally the ole girl refuses to shutdown. If i fiddle with the selector knob (always within the white band) i can usually find a happy spot where it will eventually shutdown. Ive got to believe the "mother board" 's white shut off band is getting narrower and narrower......or maybe the exhaust temp probe. Has anyone else had this issue? Thanks in advance

Skillet

 

[Tonyray]

I have a P68 that i have always run in stove temp mode. This year occasionally the ole girl refuses to shutdown. If i fiddle with the selector knob (always within the white band) i can usually find a happy spot where it will eventually shutdown. Ive got to believe the "mother board" 's white shut off band is getting narrower and narrower......or maybe the exhaust temp probe. Has anyone else had this issue? Thanks in advance

Skillet

have read where the pods[ behind the knobs] can get dirty and need to be sprayed with some electronics cleaner and worked back/forth.. while stove is offcourse.

 

[jackman]

It's a common problem. The potentiometers (pots) get dirty and develop dead spots. Shutdown and unplug the stove and spray the knobs with DeOxit. If that doesn't fix it you'll need to replace the pots if you can solder in new ones or replace the entire board.

 

[Havilcek stole the ball]

I've had this problem for years and have just worked around it. Interested to try this solution - do the knobs need to be pulled off before spraying, or just work the spray in behind them?

 

[Washed-Up]

You need to unplug the stove and remove the board, then pull the knobs off....then spray behind the knobs

 

[gfreek]

You need to unplug the stove and remove the board, then pull the knobs off....then spray behind the knobs

You'll see the 3 potentiometers on the back side of the board, use the spray , turn knobs back and forth, follow directions on the can..

 

[homeskillet]

You'll see the 3 potentiometers on the back side of the board, use the spray , turn knobs back and forth, follow directions on the can..

My P68 is a 2008 model and there is no "off" detent that can be felt for the knob to rest in......just a white band that indicates off. Is there supposed to be a noticeable "off" detent? I wonder if early models circuit cards didnt have a built in detent......or if mine is completely worn out.

 

[jjbroze]

I have a 2008 Acentra insert, my old control board, which I replaced, did not have the "off" detent. My new control board does. My insert refused to shut down, replaced the ESP and the control board, all is well now.

 

[gfreek]

I have a 2008 Acentra insert, my old control board, which I replaced, did not have the "off" detent. My new control board does. My insert refused to shut down, replaced the ESP and the control board, all is well now.

ESP is another option, ever been replaced?..I keep a backup in my parts bin...That you have to "fiddle" with the knob, it may need cleaning ...Are you the original owner of the P68 that won't shut down ?

 

[Ssyko]

A good video about the cleaners

 

[homeskillet]

ESP is another option, ever been replaced?..I keep a backup in my parts bin...That you have to "fiddle" with the knob, it may need cleaning ...Are you the original owner of the P68 that won't shut down ?

2nd owner, ive owned it for 4 years. It was in disrepair when i bought it and i only paid 350 dollars for it sooooo i cant complain. ive changed alot of parts on it (feed weldment, burnpot, auger, exhaust fan/motor and convection fan) but not the circuit card or esp. speaking of ESP.......question, I can use either the red or the black esp, if my dip switches are correct or the given color....right???

 

[jackman]

I have a 2008 Acentra insert, my old control board, which I replaced, did not have the "off" detent. My new control board does. My insert refused to shut down, replaced the ESP and the control board, all is well now.

My stove is similar and there is no detent for the off position.

 

[gfreek]

2nd owner, ive owned it for 4 years. It was in disrepair when i bought it and i only paid 350 dollars for it sooooo i cant complain. ive changed alot of parts on it (feed weldment, burnpot, auger, exhaust fan/motor and convection fan) but not the circuit card or esp. speaking of ESP.......question, I can use either the red or the black esp, if my dip switches are correct or the given color....right???

Someone here should be able to answer that, but in the mean time :

http://rs.woodmanspartsplus.com/company_41/Harman%20Dipswitch%20Reference%20Chart.pdf

 

[jjbroze]

I went from a red ESP to a black ESP on my Accentra insert when I updated the control board. The data sheet settings for the dip switches, that came with board, will tell you which switches to set on or off for which color ESP.

 

[bobnoffs]

i have had this problem and about every other unrelated one you can think of and in the end it is dirty pots. i have gotten into the habit of turning the knobs on the pots back and forth several times a week. this has cured every problem that has come along. i also used the spray cleaner.
it would be great to locate a replacement pot source. i have never seen it. i bought some so called replacement pots from someone on this site but they weren't even close. oh well, he meant well.
i even have a new control board i bought but never installed cuz i took to turning those pot knobs.
funny. i also have a new uninstalled combustion motor i never installed cuz the funny noise went way several years ago and never came back.
come to think of it all i have ever replaced is an esp probe.

 

[Ssyko]

What was wrong with the pots? You are the first one ive heard of that had an issue.

 

[bobnoffs]

What was wrong with the pots? You are the first one ive heard of that had an issue.

i have read about problems with contact surfaces of the pots many times on this forum. it you read this forum i find it surprising this is new to you.

 

[gfreek]

What was wrong with the pots? You are the first one ive heard of that had an issue.

i have read about problems with contact surfaces of the pots many times on this forum. it you read this forum i find it surprising this is new to you.

Think he meant replacement pots ??

 

[Ssyko]

Think he meant replacement pots ??

exactly

the harman pot’s I have are cermet, non detent and i have had 0 negative feedback in 2 years. I do welcome any and all feedback.

 

[bobnoffs]

oh, you mean what was wrong with the replacement pots. as i remember they didn't have the correct placement of the solder pins. i thought you were asking what was wrong with the harmon [ots.

 

[Ssyko]

oh, you mean what was wrong with the replacement pots. as i remember they didn't have the correct placement of the solder pins. i thought you were asking what was wrong with the harmon [ots.

the next time you have the board out could you post pictures of both sides of your board? And the age / serial number of the stove.

 

[bobnoffs]

sure