I have a bryant 395C gas furnace and the inducer motor assembly is making noise.

The motor seems fine and the furnace operates normally, but there is a plastic wheel attached to the end of the motor that is rattling when the motor runs.

I've looked at pictures of many inducer motor assemblies and none of them have a wheel such as this.

The plastic wheel fits loosly on the motor shaft and can be spun by hand with the motor off. It spins with the motor on only by being loosly fitted to the shaft.

Does anyone know what it's purpose is? It seems to only give an indication that the motor is running.

It's loose fit seems to be the cause of the rattle, so it may be worn and meant to fit snugly on the shaft so that it won't rattle.

What do you think?

Thanks for any help.

I don't claim to the furnace master, but my thinking is that your suspicion about the wheel needing to be tight is correct. I'm assuming there is a nut (or there was a nut) that would hold it tight to the shaft. Is the shaft threaded? Can you pull the wheel off? Is is cracked in the area that goes on the shaft?

If is strictly a pressure fit, and worn, you could try to put some silicone caulk on the shaft and then push the wheel on. Unfortunately, you'll need about 24 hours of not running it to allow the caulk to cure.

I think if you can get it tight to the shaft, you'll be back in business.

The wheel is probably a flywheel to smooth out the speed of the inducer motor, but that is strictly a guess.

Best of luck,
WallyH

This is a cooling fan for the inducer motor. Wally gave you good advice about how to tighten it to the shaft

The attached pic is of an inducer assembly that uses the same cooling impeller. Look closely at the clip on the exposed end of the shaft. If it is missing, the impeller will likely vibrate. If present, but loose, carefully twist it off, place on a hard surface & tap with a hammer to compress the tabs.