1/15 hp blower motor
1/15 hp blower motor
I have been looking through the forums wanting to make my first post a correct one but I haven't found anything that relates directly to what I'm sure is a minor issue.
I am on my Condo board and are trying to rectify some horrible repairs our recently released property management company has performed, one being seriously hampered dryers. I am repairing the ducts that are plugged and found a serious bottleneck in the form of a duct boost fan in the attic.
It was killed off by the a**holes that installed a new furnace in 2012 and new wired the fan back in and has collected so much lint and other contaminants it resembles something an 800lb yeti coughed up. So I pulled the unit for cleaning and testing. It is a Braun 1/15 hp duct booster with an 9" squirrel cage which should handle the job fairly easily (it's only a 3 storey building).
I did wire it back in to see if it worked at all but just sat humming without motion but being literally buried in 2" of lint barely visible I blamed weight for it's inability to spin. However it would freewheel by hand rather easily. It has been cleaned and I split the motor to uncover fairly seized bearings with cracked plastic spacers and a ton of red rust dust. The winding was in good shape and after cleaning the stator it too was in usable condition but had some big scratches on one of it's ends which I would expect with the stator walking from it's bad bearing spacers, this I can rectify easily. I reassembled the motor for a quick test and it fired up.
It was a little noisy but actually worked ok until I grabbed the outer cage wheel to see how much power it still had and then the motor seemed to jam. I tried to coax it back into motion but it seemed to fight wanting to turn but kept humming until I killed the power at which point the motor freed up. When I plugged it back in it locked up again and refused to move.
I am a little puzzled, the stator does not have enough play in it to contact the winding and the bearings are spinning like new. Would a phase shorting do this? It has no start capacitor and the only thing I can think is somewhere the winding is back feeding and stalling the motor trying to spin it in both directions at the same time, but I don't even know if it's possible and if it is why does the cage seem to grind when I move the cage still powered on?
I'm sure we're into a new motor but I'd love to know what the heck does this.