Exhaust fan motor replacement?

[zbadone]

Hello,

I have built myself a pole barn a short while ago and a friend of mine gave my a non-working industrial exhaust fan. The motor was not working.

I got it installed and just now looking to purchase a new motor for it. I'm not sure what size or type to purchase. The old motor's name plate was well worn and I couldn't read what HP rating or what speed it was.

The fan in question has blade diameter of 30" across, from tip to tip, and a pulley that is 20" in diameter. The fan has louvers in front that need to open during operation. The old motor has no pulley on it.

Any tips or help would be nice....


http://www.flickr.com/photos/9924918...n/photostream/

[egon]

Maybe check out similar sized fans and see what size motor they have.

Just guessing I'd say 2 to 3 HP. at 1750 rpm.

Egon [img]/forums/images/icons/grin.gif[/img]

[Pat]

The picture shows quite a disparity in pulley diameters so there is a serious speed reduction in the RPM of the fan vs the motor. I have to disagree with Egon on the required HP@1700 motor RPM. I think that 2-3 HP would be considerable overkill.

The best thing is to let your fingers do your investigating and look up on-line sources such as Grainger, Northern tool, McMasters Carr etc. to see what HP they sell on a 30 inch fan of similar design. I'd guess about 1 to 1-1/2 HP but don't accept Egon's WAG or my SWAG, instead look to see what the typical commercial fans of your size and design are sold with.

Pat

[Robertbrown]

The motor might not be bad, you may just need a new start capacitor.
Check the winding for a short. Does the motor shaft turn?