Harman P68 auger motor question

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JCoxBuilder

Member
Nov 3, 2017
45
Whitefield
Okay guys this may be my last question for the new year - I need more help.

A couple of years ago I replaced the auger motor on my Harman P68. We purchased this stove in 2014. I have the owners manual in hand and the auger motor that I replaced was a 4PRM with tan blade. I replaced it with one that has no blade and I’m assuming that is the one that is 6 RPM? Well I had a new control board installed and the auger motor is very hot to the touch and tbh I’m not sure I’d they adjusted the new control board for the 6 RPM because everyone it kicks in it sounds like it is suffering.

How do I know which RPM my auger motor is and how do I verify this adjustment is made on the control board?

You all may think I’m OCD but every time that auger kicks in you can definitely hear it and a hum.

EDIT I see the new auger motor is a 4 RPM but not sure if it is adjusted for a 4 RPM or 6.
 
Your new control board comes with a instruction sheet that shows the stoves it fits, and the position of the dip-switches for each stove.
 
Well, they should have left that with you, you paid for it. I posted the most common one in another thread, will see if I can find it.
 
The thing is just so loud like a very low hum and it comes on quite a bit more after the board is installed to the best of my knowledge. Maybe I’m obsessing
 
I'm not that familiar with the P68 but I've never heard of a P series stove that will let you adjust the auger motor RPM. There is a way to change the direction of the motor but not the speed that I'm aware of. If you do have a 6 RPM motor when a 4 is required it would be working harder explaining heat and noise.
 
Checking the motor RPM is as simple as removing (I guess it could be done in place also) it and plugging it into 110V outlet and counting the revs in a minute.
 
It currently has a 4 RPM Gleason auger motor attached. I verified that :) Just not sure if circuit board has a sip switch set for a 4 or a 6 and if it is set for 6 would that burn out a 4.
 
If the stove is running right other than the motor heat and noise I would bet the board is ok and you may have a defective motor. Check your voltage at the motor with a multimeter. If it's not 110/120V check your wire connections, if it is getting correct voltage we're back to a bad motor.
 
If it's 110/120V the board and wiring are fine but if the motor is loud and laboring it'll need replacement soon. Heat is a killer on small motors.
 
Oh, and none of the dip switches control auger RPM.
 
According to dip switches 1-2-3 their adjustment depends if you have a 4 rpm or 6 rpm auger as this is for the auger run time on a startup.
and in normal operation if the original was a 6 rpm and you put a 4 rpm you may have to increase the feed rate to be able to obtain the desired heat in the house because with the even screw the 4rpm will give less pellet
 
If the board was set up for a 6 rpm motor and you had a 4 rpm motor in place You would only get about 2/3 of the initial charge into the pot at start up. Both are 120v fuel is metered by run time on/off cycles. Vise versa if set for 4 rpm and you put a 6 rpm in the pot would over fill and spill into ash pan .
 
Okay guys so I went and picked up a 4 RPM new auger motor direct from store. I plan to test this and see if it helps with the noise. I also picked up a voltage tester. 2 questions

Before I remove the existing one can I disconnect it and plug it into the new one on hand and see if it sounds better? And also I read that it doesn’t matter which wire goes where on the augers is this true?
 
My harman p68 year of manufacture 2013 month august auger motor 6rpm red and black wire connect black with black and red with white and when I am in front of the stove it turns clockwise
I bought it in February 2014
 
Don't know if this has been posted here or not, but is pretty useful chart for dipswitch settings......
 

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Okay guys so I went and picked up a 4 RPM new auger motor direct from store. I plan to test this and see if it helps with the noise. I also picked up a voltage tester. 2 questions

Before I remove the existing one can I disconnect it and plug it into the new one on hand and see if it sounds better? And also I read that it doesn’t matter which wire goes where on the augers is this true?

The New auger motor will most likely sound better. However after it is connected to the auger you may or may not get some noise under load. My new aftermarket was super quiet compared to the old one. After a few years it's gotten noisy but not unbearable..
 
Ok guys so here we are. I shut down the stove and ran it in test mode. The auger sounds fine everything sounds fine except for the combustion blower. That is the culprit or a sign of it. It varies in speed to a very big degree causing it to rumble and just be all over the place. I cleaned the esp probe which is new also - the only thing at this time that I can think of is the circuit board controlling the blower in an Eratic way.

Thoughts? The sealer is coming out tomorrow and are amazing and are going to install a new board and see where we are at.
 
Be sure there is no carbon built up behind or around the edge of the combustion blower fan blade. Also if it has the small fan blade on the back by the motor make sure nothing is contacting it. I believe the combustion blower speed remains constant on a P series Harman stove, others feel free to correct me if I'm wrong. The only adjustment for it's speed is done through the small hole on the control panel and is for adjusting draft. I still feel your board is OK but having a spare is not a bad thing.