# Trane XR12 blower motor dead



## Miescha (May 18, 2013)

Unit installed 4-5 years ago. Unit model and details from label here:









Unit has been running fine last season with only routine annual maintenance. However, first 2-3 seasons unit cycled on/off constantly due to freeze switch on air handler (and frozen coils). Air flow problem resolved and all seems good until this week.

First noticed loud buzzing from unit last Sunday and on review fan was not running (but seemed to be trying to run). Could not get blades going by pushing with stick, so turned off unit. Left off overnight and back on Monday afternoon and all seemed fine again until Friday afternoon when same buzzing and no fan condition returned.

On further inspection, contactor shows clear signs of burning and is on the way out (but still working at the moment). Contactor pic here:









Disassembled exterior covers for good cleaning. Even after fan had been off for nearly 1 hour, motor was so hot I burned my hand touching it  So I'm feeling pretty confident the buzzing is from the motor being heat locked and the problem is the motor, not the contactor (yet) or the capacitor. Here is pic of motor label:









It appears I can get exact replacement motor from a number of online sources for about $150 and contact for about $80. I'm guessing the capacitor will be relatively inexpensive and should be replaced at the same time.

Anything else I'm missing? What is the method for testing the capacitor with a meter (what values should I be seeing)?

Any recommendation for parts suppliers (especially quick ship ?

I'm in St. Louis, MO if it matters.

Thanks for any help/advice.


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## sammy37 (Dec 9, 2008)

Motor doesnt have to be the same brand, anything with the same dimensions and motor specs, horsepower, rpm, voltage etc, will work.

A new capacitor is less than 10 bucks and they will tell you which one you need for the new motor.


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## JScotty (Jan 14, 2013)

Miescha said:


> Unit installed 4-5 years ago. Unit model and details from label here:
> 
> 
> 
> ...


As the above poster said you can go with a generic motor, as long as it's the same size/spec. I don't know about St Louis city ( I live out West in the suburbs ) but there are a couple places in St Peters that will sell to homeowners. One is Schepker which is just West of Mid Rivers Mall Dr on the North service rd. I also know Grainger will too & they're in the industrial complex just northwest of the intersection of 79 & 70. You may want to call ahead but I'm pretty sure both of those places should have all the parts you need and will sell them out the door to you. So you can have the parts first thing monday morning.


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## bobelectric (Mar 3, 2007)

I use www.RepairClinic.com every now and then . In your case I would try a new capacitor first.


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## Miescha (May 18, 2013)

Thanks so much for the quick replies!

Naturally, the temps blew past 90+ today. I already had the motor out, so I figured I really couldn't hurt it at this point (unless of course it was ONLY the capacitor). I cracked the case and found a crazy mess. The coils actually looked great, the rotor was really dirty, but looked fine. The bushings however, were so dry and empty that the tiny amount of grease/lube left was hardened to near granite density. They must be packed with a felt-like material b/c it was all over the inside of the housing. 

I repacked the bushings after several trips to ACE hardware - used felt washers for a car battery to repack after soaking them in oil. Cleaned down the coils and rotor with electrical engine cleaner (which specifically mentions degreasing/cleaning electric motors to my surprise). Tightened all down, tested the motor just sitting on top of the unit without the fan and fired up and ran just fine, so I bolted it in place, put on the blades and put everything back.

Its been running for a little over an hour at the moment and house has dropped from 94 to 83 F which is a start I guess (solid limestone house with slate roof and it seems everything was heat-saturated - so slow temp changes).

I can feel some heat already from the top of the unit where the motor is mounted, but I really didn't have expectation that it would run more than 10 minutes anyway, so I'll be thrilled to just drop the house temp some to make sleeping easier.

I'll source a replacement motor and capacitor tomorrow (and contact switch if possible).

Here's a few pics for anyone bored enough to have read this far


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## Miescha (May 18, 2013)

Just a quick update. 3-hrs constant running. Temp at top center of unit hasn't increased that I can tell (if I remove the plastic cap/cover and lay may full hand there it's very warm, but I can easily leave my hand in place indefinitely without any discomfort). 

Main floor is at 75 and upper level is hovering about 81. If it cools off enough I'll vent some windows to get some heat out quickly. 

I'm just surprised its still running without overheating or seizing.


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## Doc Holliday (Mar 12, 2011)

good job. hopefully you'll get away for a decent amount of time. that fan is needed to cool off the hot vapor in the condenser as it rejects the heat that was absorbed inside the home at the evaporator during saturation. without that fan you can't cool off the hot vapor nor reject heat, and your compressor (which uses a whole heck of a lot of amps on yours, btw ) will run very hot as well. 

anyways, good job and yes, expect to have a back up fan on hand by tomorrow, just in case.


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## Miescha (May 18, 2013)

Well struck out everywhere today (tried Schepker too - thanks Jscotty, but no luck). I made it clear I didn't need the same brand, and I think everyone assumed I didn't anyway. The closest match was from a local electric motor repair and replacement company. The only issue is the mounting method is different - their motor specs were identical, but used the case bolts to mount the motor whereas the original uses 4 separate screws through the unit top that thread into the motor. My thinking was just drill out the holes where needed (and they said that is what most people do) but I am concerned that any minor error would put the motor off-center and could be very, very bad. 

Since my 'rebuilt' motor is still going strong, I'll keep searching. Worst case, they have them in stock for $109 so I can always head back tomorrow if needed.

Sitting outside this evening, it was very noticeable that the fan is now much quieter than it has been lately. Previously, there was some minor wind cutting/buffeting that I attributed to the blade flexing a bit over time and not cutting through the air as well. But maybe it was a matter of lube in the motor. Either way, the quiet is nice (and interesting).


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