Harman P38 Discussion

[Wolverines8]

I have an older style Harman P38 with the two knobs only. I have always had problems with the feed rate knob. I finally found replacement pots and soldered them on. When I started the fire (manual) the stove was exhausting the fire and was on but not feeding. When I opened the door and then closed it it started to feed shortly after. I messed around with the feed rate and blower and all seemed to be working ok, until about 45 min later then it stopped feeding. The blower would come on for one second, turn off, come back on again, etc. Sometimes the blower would stay on, other times go off.

I have always had issues with this stove and I was hoping somebody else was able to fix similar issues. I do not want to spend 400 bucks for a new board! Any help or insight would be much appreciated.

 

[snoop168]

There's a part that detects the draft... Maybe that part is not working right? My part works, so what you might try to test to see if yours is: Get a fire going. Once its going like normal, try opening your door up while the fire is going. You are basically reducing the draft by doing that... What I notice with my stove is that the combustion motor seem to slow down considerably. From like 100% to the slower rate like when you are still trying to get a fire going... What I take this to mean is the draft sensor is doing its job. While this doesn't directly address the feeder, I would think if there is some safety circuit wired to the combustion motor that there must also be some sort of safety circuitry designed into the feeder and if this part is not detecting a good enough draft it will no longer feed more pellets and also slow the motor down.

I've found your post because my feed rate knob is touchy and I think I need a new pot. Can you point me in the right direction of where you bought yours? I had some dead spots on the knob but now its progressed to the point where you need to sort of push on the knob in any position to make it make good contact and even then, if I walk away and come back an hour later my fire is out... My problem is definitely the knob.

 

[gfreek]

Pots are on ebay...model specific.. Feed starts by temperature on ESP.. Feed rate by knob..A sealed hopper and fire box critical for feed. Check hopper lid gasket, door gasket ( you can pinch it a little for a better seal), vacuum sensor hose.., clean and good ESP(exhaust sensor probe).. just some ideas..

 

[GeHmTS]

Are you sure you're not operating your stove in fireplace mode (manual stove temp)?