A couple of months ago some of you here helped me to diagnose a 3 year old Bryant 352MAV that was giving error code 32. I replaced the induced draft blower and it's working fine. That thread is called "Bryant 352MAV and error code 32"

However I'm not sure about the fan on the induced draft blower. The furnace is installed in the attic (not suspended) and I can hear it spin up and adjust it's speed as the furnace gets ready to output some heat. I am positive that the original fan didn't make that noise, and I'm positive that the old fan didn't make the noise even after I'd make my stopgap fix of pulling the entire unit apart and using triflow on it's bearings.

It's a vibration kind of noise not a squeak or friction sound. So the fan (which is a substantial piece of plastic) must be out of balance.

I can't imagine that reseating the induced draft blower unit would have any impact on this. So the only choices seem to be to either forget about it, or to try to replace the unit again. The furnace company that provided the replacement didn't allow me to keep the old one, so I can't replace one fan with the other.

Keeping it has obvious downsides; it's not a loud sound but it's not exactly engaging to listen to. And I suppose it's possible that the vibration will eventually help the unit fail again, at a time when it'll certainly be out of warranty.

I am not sure that the furnace company will be willing to get me another induced draft blower. I've not asked yet. It works, after all.

Wow I'm so disappointed by the quality of these units.

Quality of parts has been getting worse for years and now that china makes some of them it is impossible to get any quality. You might test the waters with the company that sold you the assembly to see if they will warranty the one you have now. I am sure you have mand sure it is that part that is making the noise?

It has to be that part. I know the sound pattern that the inductor makes as it spins up now - first at max rpms, then as the burners kick in (which I can also hear), down about 10%, and so forth.

See what you can do with the parts supplier on a exchange.

There have been some vibration-related noise issues with the 352 inducers, particularly when running at the low speed. Unfortunately, quality control testing cannot always reveal this as effectively as field application can. If you feel the noise is excessive, exchange it for another. This issue should be no surprise to the parts supplier, and they should not object to the exchange. I have dealt with this myself, many times, on brand-new units. Good luck-although I don't think you'll need it.;)