I have Aprialire 8100 Air Exchanger that had been working okay until a last few days. Until now, when I turned it on, the motor made a very loud humming and not spin at all.

I disassembled the parts and checked for the problem. The capacitor seems okay in term of its size (no pop and swelling) and resistance.

I guessed my motor is gone.

Here is its spec:
Fasco No. 7090-1101 Type U90B1 115V 60Hz 1.4A HP1/10 thermally protected class B 4 MFD 370 VAC Cap.

Here are my questions:
How can I fix the motor?
If not, can I buy the motor replacement?
I have been checking on the internet for the motor replacement, but I could not find the one with the same spec and the exact size.
I called to the Fasco and they give me the replacement part from other company: Aprilaire 5152
All I need is the motor. How can I find them?

Any suggestion is greatly appreciated.

Looks like the motor itself might not be available. It seems possibly due to a design change they want you to replace the blower assembly.

Aprilaire Parts & Supplies Aprilaire 5152 BLOWER ASSEMBLY

Aprilaire 5152 Blower Assembly

The price seems to be expensive.
I would take the motor to a local motor repair shop and see if they can match it up or rebuild the old one. Grainger has a lot of small dubble shaft motors.

My Perfectaire (Aprilaire) 8100 ERV Fasco electric motor quit pushing air two days ago and I suspect the bearings are bad. This Fasco 7090-1101 1/10 HP motor has been replaced by 7190-1101 and I've read that this motor requires no continuing lubrication every 6 months. If you go through a local HVAC distributor (See the Aprilaire website for the list by zip) you might get a better price ($400 or so, compared with the list of $667).

There are plenty of 1/10 HP motors from other vendors, but the issue is getting one that dimensionally meets the exact hole register within the air box.

Postascript: I did take the broken Fasco motor (the twin shaft could still be rotated) to a local motor repair shop to see about having the bearing replaced. Will post that result once known.

My Aprilaire 8100 fan starting chirping a few days ago. Since I had bought an as new demo unit a few months ago, it was not a problem. I removed and installed the extra blower. That gave me time to rebuild the old fan.
In taking the fan motor apart I found that there are two sealed ball bearings in the motor. I removed the old bearings and ordered new ones for $4 each. The bearing number is NMB: RI-1438DD.

Howard

Mine has the same problem. The rotor would no longer turn. After removing about 20 screws to get down to the motor I find printed on it "oil every 6 months with SAE20". You have to be kidding me. There is at least one engineer at Aprilaire that should be talked to. Mine lasted 18 seasons before failing. It does not have replaceable bearings. It just has oil filled fiber bushings. I see that FASCO closed the plant where the motor was made and offers no replacement. The frame size of the motor is a bastard size. I think $550 is too much for a replacement that might last 18 more years. I found someone selling them for $392.95 including shipping.