25-PDVC auger motor overheating??

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Maritimer

New Member
Nov 9, 2008
20
Eastern Canada
I have an Englander 25-pdvc and I know from touching my bottom auger motor it is hot enough to burn my finger. I'm also starting to see some grease leaking out of the bearing probably due to the heat. I then seen on the motor that it was Inter. duty on it. I have some experience in motors and this means intermittent duty and since the bottom auger turns all the time wouldn't that mean that it should be a continuous duty motor. My buddy has an older 25-pdvc stove and when I seen him we took his top auger motor out which never gets hot and applied 115 vac (no load) and after 20 min. it got so hot that even the gear box was getting too hot to touch. I looked into Merkle and sent an e-mail and the Englander part is a proprietary part and I couldn't get any info. I have seen from other websites similar motors/gearboxes.

Don't get me wrong about the pellet stove, in general it works well and heats my 1500 sqft home. I'm thinking long term maintenance and costs. I bought it to save money.

If I'm wrong about the motor please let me know. The above comments are observations only. I'm not a motor expert.
 
Does your auger make any noise? I noticed my lower motor shaft was too hot to touch accompanied by periodic squealing. Carbon build up in the auger tube next to the burn pot can bind the auger increasing motor heat. I found that scraping the carbon away with a screwdriver weekly keeps things quieter and cooler. There is procedure to center the auger if necessary but my guess is cleaning is all that is necessary.
 
I clean the carbon buildup at least once a week and there is no sqeeling or unusual noises. Its the heating aspect which concerns me. The test I mentioned earlier with the motor was while it was on a test bench with nothing hooked up to it such as the auger and it still was very hot to the touch.
 
we've used these motors for many years and havent seen an unusually high amount of motor failures to date. my own personal stove has run since dec of 2004 with its original motors installed with no issues, and there are stoves much older than mine still running on original equipment. this is not to say they never fail , but premature failures are not really that common. as for the temperature, yeah they get pretty durned hot but they hold up quite well even at the temperatures they are being operated at.
 
I still notice a considerable difference considerable difference in the temperature betweeen the upper and lower motor shaft temerature. With my stove on the 1-1 setting: The upper shaft is about 115 degrees and the lower is 150 degrees as measured with a Harbor Freight Cen-Tech Laser Temp gage. May not be absolutely accurate but representative of a considerable difference. I can hold my finger on the lower shaft about two seconds before discomfort. This is my second season, I burned three ton of pellets last season. Perhaps this will give you a baseline for comparison. It would concern me if in fact the motors are not contunuous duty but perhaps the motors are not operating at the maximum capacity in this application.
 
Thanks for your comments. My wife has told me that I can be too anal. That may not be a bad thing most of the time. Its my first season with the stove so there's going to be a breaking in period for myself and the stove.
 
Maritimer,

You are right about the motor being wrong. For Englander to say the motor is hot but seems to be ok is ridiculous. The motor is hot because it is not designed to be used for continuous duty. Anyone that knows these motor will tell you that it will overheat and fail.
 
Is the motor getting hotter because it is closer to the fire and getting some extra heat from the conduction through auger itself? or all these tests without a fire?
 
Bass3139 said:
Maritimer,

You are right about the motor being wrong. For Englander to say the motor is hot but seems to be ok is ridiculous. The motor is hot because it is not designed to be used for continuous duty. Anyone that knows these motor will tell you that it will overheat and fail.

This has been my suspicion but unconfirmed. My story is here: https://www.hearth.com/econtent/index.php/forums/viewthread/32191/

I brought a failed motor to a local electric motor repair shop. At $70 per hour labor i am not sure i want to go that route. I will rewind it myself.

I bench tested this motor. It works when the stove is cold but the motor stops working after about 3 hours of use. It will work again once cool.

My bench testing showed the same as you ..... the motor is making excessive heat. Enough to burn my fingers. The heat starts at the motor frame and spreads to the windings. After 2 hours i could not touch any part of the motor.
 
PunKid8888 said:
Is the motor getting hotter because it is closer to the fire and getting some extra heat from the conduction through auger itself? or all these tests without a fire?

I ran tests also and the motor does not get hot because of the fire. It simply gets hot because it is the wrong motor for this function. An intermittant motor will burn up when required to do continuous duty.
 
I still have some concerns about the motor and its not just that its too hot to touch but also I'm seeing bearing grease or other type of grease leaking out. When I first noticed the motor/gears getting hot was when it was attached to the stove under running conditions. I then disconnected a motor and tested it on the bench. After 20 minutes or so it would burn my fingers if I touched it for more than a couple of seconds. I don't dispute Mike when he says they last awhile, but could they last longer if they were a different type of motor or a stronger one?? As I have said I'm new to the pellet stove community and I'm happy wth the stove generally. I just want a stove that won't cost an arm and a leg over time. I guess we'll see.
 
I would think the lower motor would be hotter as it is always running VS the upper motor only runs as the heat setting depicts,
So lower motor should wear out before upper motor in due time so why not rotate motors every year sort of like rotating tires.

Not sure about the gear grease leaking are those units sealed or vented?
 
25pdvc - well all the grease leaked out when hot. i got my grease gun, and the high temp brake grease i use for my car


I am going to give that a try thx,
 
Its not the auger bearings that were leaking grease, it came from around the motor bearing. You could visually see it around the opposite site of the auger. Also my auger bearings do not get as hot as the motor assembly.
 
Maritimer said:
Its not the auger bearings that were leaking grease, it came from around the motor bearing. You could visually see it around the opposite site of the auger. Also my auger bearings do not get as hot as the motor assembly.

if the gearbox is pushing out grease then it could be an issue i need to address, how about giving my shop a call and chat with me or one of my techs, it could be a bad seal in the gearbox , if so it would eventually leak out the rest of the grease which obviously wouldnt be good for the motor, or, it could be that the gearbox was overfilled with grease and as its expanded its forced its way out , which also could damage the seal , same thing , call my shop and we'll get you taken care of
 
stoveguy2esw said:
Maritimer said:
Its not the auger bearings that were leaking grease, it came from around the motor bearing. You could visually see it around the opposite site of the auger. Also my auger bearings do not get as hot as the motor assembly.

if the gearbox is pushing out grease then it could be an issue i need to address, how about giving my shop a call and chat with me or one of my techs, it could be a bad seal in the gearbox , if so it would eventually leak out the rest of the grease which obviously wouldnt be good for the motor, or, it could be that the gearbox was overfilled with grease and as its expanded its forced its way out , which also could damage the seal , same thing , call my shop and we'll get you taken care of


Thanks Mike
You hit the problem right on the head. I appreciate the quick responses to my PM's and directing me to the warrenty site. I did choose right when I bought this stove.

Regards
 
Bass3139 said:
I ran tests also and the motor does not get hot because of the fire. It simply gets hot because it is the wrong motor for this function. An intermittant motor will burn up when required to do continuous duty.

I ran a test this weekend. Motor is outside of the stove. Run on a bench with no load applied. All temps in F and measured with a non contact Laser thermometer.

Time Run-------Motor Frame-----Windings------Gearbox case
0 min------------73------------------72-------------72
40 min-----------170----------------160------------98
90 min-----------180----------------180------------115

Motor frame and windings stayed at that temp and didnt increase beyond 180. Not sure how i could do a real world test to see the temp while its in the stove and running. During the bench test the unit has ~72 degree ambient air. I dont know what the temp would be while inside the stove with a fire burning. Obviously the ambient air in there is much higher than 72.
 
HD41 said:
I still notice a considerable difference considerable difference in the temperature betweeen the upper and lower motor shaft temerature. With my stove on the 1-1 setting: The upper shaft is about 115 degrees and the lower is 150 degrees as measured with a Harbor Freight Cen-Tech Laser Temp gage. May not be absolutely accurate but representative of a considerable difference. I can hold my finger on the lower shaft about two seconds before discomfort. This is my second season, I burned three ton of pellets last season. Perhaps this will give you a baseline for comparison. It would concern me if in fact the motors are not contunuous duty but perhaps the motors are not operating at the maximum capacity in this application.

In 2008 I considered these temperatures normal but now have a problem that may be related to auger motor bearing temperature. The lower auger quit turning so I thought I would be without stove heat until I got another motor. There is a Grainger close by but this is Sunday. With nothing to lose, I removed the motor and bench tested finding it still would not turn. Found upon disassembly that the armature could be turned but with difficulty. I removed the rear bearing cap, applied WD40 until the shaft turned freely. Reassembled, bench tested and motor functioned properly. Put the motor back in and the stove was back on line again. What is interesting is that now after running 8 hours, bearing temperatures are upper 99 degrees and lower 130 degrees.

I probably should buy a backup motor. Granger and Gleason-Avery are $80+, I see a motor on Amazon for $56, are they any good? http://www.amazon.com/Pellet-Stove-Auger-Whitfield-Merkle-Korff/dp/B0032D26I6

Nothing else has been done to the stove. I doubt that I am the only one that has revived an auger motor, any ideas on how much life is left in the motor?
 
Like you said, you have nothing to lose by lubing the present one and see how long it will go. But having a spare is a good idea.

As far as which one to get, the Gleason-Avery units are beefier, have better bearings that can be oiled w/o removing the cap, have ball bearings in the gearcase, and have a larger stack (more power)......that's the brand I'd get if I was buying one.

www.gleasonavery.com/catalog/pellet-corn-stove-motors.html
 
Ive got 2 gleason averys auger motors in my stove now and it is running very well...24 hrs a day...,,now if I can just find a quieter room blower.....any ideas?..ive cleaned it and balanced it (to say)..Ive been trying different sound deafining material , which helps , but is not the answer..here's a pic of the gleason auger motor and original equipment auger motors(before I changed out the second motor.the motor farthest away is the Gleason motor)
 

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KINGOFTHENORTH said:
.....now if I can just find a quieter room blower.....any ideas?..ive cleaned it and balanced it (to say)..Ive been trying different sound deafining material , which helps , but is not the answer......

From my experience removing & cleaning room air blowers.....when I clean the blower out of the stove, oil it, and then test run it on my workbench, it's not as loud as it is installed in the stove.

Most of the noise seems to be from the air going through the heat exchanger passageways. This has been true (for me) on both my Englander and my Astoria stoves (both have very similar blowers).
 
Fast forward to 2012, after seeing auger motor posts for one reason or another I decided the motor I revived with WD40 in January 2011 may be ready to let me down. A few months ago I decided to buy 2 RPM ECM heavy duty motors from Surplus Center for $18.99 that another member tried. It is a heavy duty motor 1 1/16" field stack vs the 3/4" Merkle-Korff. I first put the 2 RPM motor on the upper auger and it worked OK but tended to overfeed. I then moved the 2 RPM motor to the lower auger and put the Original revived lower Englander/Merkle-Korff motor on the upper auger and will run it to failure. I have the original upper auger motor for a spare. By the way the 1 RPM Englander actually clocks 1.3 RPM in operation. About 2 months and the 2 RPM motor works fine in the lower auger.
augermotor.jpgaugerTopView.jpg
 
Hello HD41

The motor I ordered from CSH is coming this Wed. Sounds like a good deal for $59.95 and it is a 1 RPM motor.

By calling their toll free # they will set it for CCW rotation looking at it from the front of the shaft!
http://www.cshincorporated.com/product_info.php/products_id/10184

Here is more info on it from the source.
"Heavy Duty Strongest Available Design"
http://www.multiproducts.com/ac-gearmotors/ac-9000.htm
thanks Don, i also ordered the same motor this tuesday 4/10 it's here already and running great
i have my pdvc back finally
also came with the correct rotation
 
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