Diagnosing R&M 1404 Issue

[Jon Kovach]

I need a hand diagnosing what has burned out / gone bad in my fan.

I had my very nice R&M 1404 on top of the fireplace mantle and would run it to move hot air while the fireplace was on. 

it would get warm but never had any issue until….

the fireplace and fan were left on for 2 days unbeknownst to me. The fan was left running on low but when I found it, the blades were not moving, it was humming, and the motor was hot to the touch.  

Now the fan runs much slower on all 3 speeds. It barely moves on the lowest speed. 

any ideas what was damaged? Do you think I need a stator rewind?

I'm super bummed about this so don’t make fun of me too bad for having the fan above the fireplace. 

thanks,
jon

[Bill Dunlap]

As far as I know, there are two different set ups for that fan. One uses a tap off the speed coil for the start windings, and the other uses the tap and a resistance winding for the start windings. The last is rather complicated design that needs a careful balance. If you determine which type you have,, and it's the latter one,  you might find one or the other circuits not working right. Other than that, heat can evaporate the oil in the bearings causing it to run slow and hot.

[Jon Kovach]

Thanks Bill. I’ll check the oil cups and wicks to make sure the bearings are being lubricated. That would be great if that’s all it needs.