Question about fan motor

Don't know exactly what you mean by "residential air handler", but the blower motor in a lot of home furnaces - including mine - runs 24/365.

I'd try a new capacitor.

Tove

Second that, and while your hands are dirty see if there's any oil reservoirs that might benefit from lube, if that motor doesn't have sealed ball beatings.

I know my home's air handler motors use sleeve bearings, I had to press a new bearing in one motor last year when I didn't think about oiling it and it started squealing. The shaft didn't look perfect either, but it's made it so far.

Out of sight, out of mind.

Jeff

The biggest mistake most people make when making one of these the first time is that they fail to put a restriction in the outlet. These fans are designed to run into a restricted outlet (the coils, and ducting of the system). If you run one wide open on the outlet without the restriction it tends to overload the motor since there's to much air moving over the squirrel cage.

Wayne Cook Shamrock, TX

Thanks for the comments, guys. I noticed when I walked close to the inlet, the noise from the blower changed somewhat. I'll try choking it down a bit after the new capacitor. The fan motor, while wired up for a single speed in the A/C handler, has four speeds. I wired it up through a scrounged 4 position switch and now have four speeds. The highest actually blows so hard that the fan moves backward on its rollers, so I can't use the highest speed.

Gary Brady Austin, TX