Englander 25-PDVC upper auger motor problem

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donbryce

Member
Jan 8, 2009
110
NB Canada
Background: Purchased stove in Sept 2008, started burning in Nov. and have gone through about 35 bags. About 2 weeks ago, the fire started to die, so I checked the hopper and there was that usual open funnel directly over the auger, you know, when the pellets get low and they don't sift down the sides. So I manually pushed them over to get the feed started again, but since it was late, and it looked like I'd need to restart to get the fire back, I just put it into shutdown and went to bed.

Next morning, about 5:30, I filled the hopper, started it up again and went back to bed. When I got up a couple hours later, the panel had an 'E-2' error, so I checked the burn pot and it looked like no fire due to no pellets. So, I removed the back panel and tried another startup, noticing that the lower auger motor was turning, and waited for the upper one to start. It never did, and the stove again went into error mode.

Next, I removed all the pellets from the hopper, and noticed that there was a lot of fine dust mixed with the pellets in the visible part of the upper auger. I shop-vacuumed all of this out, and tried to move the auger by reaching in from the hopper opening. It wouldn't turn at all clockwise, and turning it counter-clockwise (from the front), and releasing it, you could hear the motor drop down onto it's shelf (this sounded like the occasional 'clunking' I'd heard since new). I figured that this wasn't a good test anyway, since I would've been fighting the gear reduction on the motor by trying to turn the auger still connected. I reversed the leads to the motors, pushed the 'on' button, and saw that the upper one wasn't turning. After unplugging the stove, I then put my finger into the space on the motors between the armature and gearbox, and noticed that the lower one could easily be spun, but the upper was jammed solid.

Out came the DVD and I removed the motor from the stove and took it into the shop, thinking that there must be something inside the gearbox broken or stuck. Before disassembling, I used a small screwdriver and pushed gently on the edge of the armature, and lo and behold, the armature now spun freely. I made up a test lead and ran it from the wall socket for about 10 minutes, ran just fine. I put a couple of drops of light oil on the bushings, holding the motor assembly so it would drain into them, then put everything back together.

It's been running great ever since. I called tech support today to document this, and to ask if he thought there might have been a problem inside the gearbox, which to me, would justify a warranty replacement, so I can rest assured that I won't be out of heat if it goes bad again for good. He felt very sure that the problem was due to a particle of something lodged in the motor armature/core, and I probably dislodged it with the screwdriver. I didn't notice anything fall out on the bench, but accepted this as a valid explanation. He also said I could have tried this with the motor still on the stove, so I'll pass that tidbit along. I was afraid to break something inside the gearbox, but he didn't seem to be concerned about that possibility.

Bottom line is that Englander feel that these motors are quite well built and reliable, and most problems with them are not involved with the gearbox internals. Basically, if the gearbox fails, it would not be salvageable by turning the armature manually, it just wouldn't turn the output shaft at all when the input shaft is turned.

I'd like to know if anyone here has opened up one of these gearboxes, ideally with pictures showing how the motor shaft is connected to the first gear, and what is in there that could be repaired if necessary, since I consider myself capable of doing these types of repairs and would have to if the need arose. Even just temporarily waiting for a replacement motor.....and does this analysis sound right? Could something in there fail and then work again just by pushing on the armature? Like I said, I think I would have noticed a particle of pellet or whatever falling out right there on the bench if there was one.
 
I have a lot of experience interrogating the Merkle Korff gearmotor that Englander uses. I would say with a high degree of certaintity that failures occur due to failed motor windings.

You could take the motor assembly (not the whole gearbox just the thing that looks like the transformer) off your lower motor and put it in your upper motor and see if the problem follows the part.

Here is some history.

https://www.hearth.com/econtent/index.php/forums/viewthread/34017/

https://www.hearth.com/econtent/index.php/forums/viewthread/31098/

https://www.hearth.com/econtent/index.php/forums/viewthread/33363/

https://www.hearth.com/econtent/index.php/forums/viewthread/32191/


Happy reading.
 
Thanks for taking the time to assemble those links NES. I have previously read yours in detail, and I'm sure the others have been scanned too. Unfortunately, all I can get from your pictures is that the motor/armature shaft appears to have no clip on the end and simply fits into the gearbox 'hole' and is held in by the 4 (?) screws which fasten the motor to the gearbox, right? Have you ever opened up one of those gearboxes?
 
Here's a pic of an englander 25 pdc auger motor gear box opened up. Sorry, it's not the best of pics, and I'm not cleaning off the grease for a better look. This is a motor that went bad on me about a year ago. The part of the gear box on the left is the one that attaches to the auger.

 

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THANK YOU! As I suspected, there's no 'rocket science' here. Those gears look like nylon, except for the small steel one, top upper right, right half. I assume that the steel shaft sticking up through the gear, meshed with this small steel gear, is the armature shaft, as I can just make out a flat on it.

From this I am pretty certain that failure inside this gearbox would be highly unlikely (but not impossible), since the motor would not have enough torque to strip a gear tooth, or rip one from it's post, in the event of an auger jam. I'd think the armature would simply stop turning, the motor would overheat (unless there is a fuse somewhere, or the circuit board can sense this condition), and the winding wire would then melt and break.

In my case, since it was possible to free up the motor with a screwdriver by pushing on the edge of the armature, and it's been working fine since, I'd have to agree with the Englander tech that something must have gotten wedged in there. Not hard to imagine, since you can easily see the rear end of the both armatures through the big hole in the backing plate of the stove. My location is right in the livingroom, lots of traffic around the stove, we have a cat (hair everywhere), and we all know how filling the hopper can produce lots of dust.

My thanks again to both of you. It's too bad that the electrical portion of the motor/gearbox assembly isn't available as a separate part from Englander. There must be lots of perfectly good gearboxes out there with bad motors attached. I'd think that the $130.00 cost of the whole thing could be halved or better if one only needed to change out the C frame/armature....
 
donbryce said:
THAN

My thanks again to both of you. It's too bad that the electrical portion of the motor/gearbox assembly isn't available as a separate part from Englander. There must be lots of perfectly good gearboxes out there with bad motors attached. I'd think that the $130.00 cost of the whole thing could be halved or better if one only needed to change out the C frame/armature....

Below quote is buried in one of my other posts and it mentions where i bought a gearmotor for 79.95. You can also go to Granger and buy just the motor for about $17. I did not verify the RPM on the Granger motor matches the MK. It is "physically the same". Also the shaft of the Granger motor would need to be modified on the end to mesh into the gearbox. I agree that it would be VERY difficult to damage the gearbox.

I dont think Englander is inclined to sell you at $20 motor assy when they can sell you a $130 gearmotor assy that they probably pay ~$70 for from MK. I also tried to buy the motor assy direct from MK and they wont sell it without the gearbox. You can buy the Gearmotor direct from MK for half of what it costs through Englander. I will never buy another MK until Englander confirms the failures are not motor related.

[quote author="NEStoveOwner" date="1232796504"]

FYR, the Auger Motor is also called an AC Gearmotor, the electric portion of the gearbox is a C Frame Shaded Pole motor.

I found some on Granger for $82. http://www.grainger.com/Grainger/items/1LNG2

I think it would have been up to the task, there was one other model with slightly more torque that might have been better.



Next i stumbled upon Gleason Avery (GA)

http://www.gleasonavery.com/catalog/pellet-corn-stove-motors.html

They offer a line of pellet stove motors for $79.95. I took a chance and bought one. The photo below is a side by side of the two motors.

The physical design differences:

GA Armature = 1 1/8", MK Armature = 13/16"
GA terminals are soldered, MK terminals are crimped (the pic shows soldered because i did).
GA has a gasket sealing gearbox halves, MK doesnt
GA uses rivets to secure the two sections of motor frame, MK slides them like a jigsaw
GA uses a sealed bearing, MK uses sintered bronze
GA operating current (no load) = .35A, MK operating current (no load) = .49A - my actual measurements
GA operating temp (no load) = 101F, MK operating temp (no load) = 180F - my actual measurements


You can order any motor from GA in CW or CCW. You can also reverse direction yourself by removing the bobbin (windings) and flipping it over.

A lot of people bashed me because Mike is a good guy and they think because they have an Englander that works fine, i must be the idiot. Well my stove doesnt work fine. I like Mike too but when i started on this investigation Englander (not Mike) wanted me to spend $130 on a $73 motor that i have no confidence in. Mike has offered to investigate but that hasnt happened yet. I am still going to try and coordinate with Mike. Id like to see if he can figure if failed motors are the symptom and not the cause.
 
NEStoveOwner said:
Below quote is buried in one of my other posts and it mentions where i bought a gearmotor for 79.95. You can also go to Granger and buy just the motor for about $17. I did not verify the RPM on the Granger motor matches the MK. It is "physically the same". Also the shaft of the Granger motor would need to be modified on the end to mesh into the gearbox.
NEStoveOwner said:
OK, I'm with you now. I couldn't find the $17.00 motor on Granger though, that would fit their 1LNG2. That 1LNG2 motor is rated at 1RPM, as you note, and I wonder if it would fit the Englander/MK gearbox?.
 
donbryce said:
THANK YOU! As I suspected, there's no 'rocket science' here. Those gears look like nylon, except for the small steel one, top upper right, right half. I assume that the steel shaft sticking up through the gear, meshed with this small steel gear, is the armature shaft, as I can just make out a flat on it.

From this I am pretty certain that failure inside this gearbox would be highly unlikely (but not impossible), since the motor would not have enough torque to strip a gear tooth, or rip one from it's post, in the event of an auger jam. I'd think the armature would simply stop turning, the motor would overheat (unless there is a fuse somewhere, or the circuit board can sense this condition), and the winding wire would then melt and break.

In my case, since it was possible to free up the motor with a screwdriver by pushing on the edge of the armature, and it's been working fine since, I'd have to agree with the Englander tech that something must have gotten wedged in there. Not hard to imagine, since you can easily see the rear end of the both armatures through the big hole in the backing plate of the stove. My location is right in the livingroom, lots of traffic around the stove, we have a cat (hair everywhere), and we all know how filling the hopper can produce lots of dust.

My thanks again to both of you. It's too bad that the electrical portion of the motor/gearbox assembly isn't available as a separate part from Englander. There must be lots of perfectly good gearboxes out there with bad motors attached. I'd think that the $130.00 cost of the whole thing could be halved or better if one only needed to change out the C frame/armature....


All the gears are metal, not nylon. just lettin ya know.
 
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