Wednesday, March 12, 2014

swamp-cooler-motor-stops-and-just-buzzes



OK, this issue started last summer...the swamp cooler is running, either HI or LO speed (two speed 1/2 HP motor), then just slows down, stops and buzzes. The motor may run fine for several days or weeks at a time. When I turn it off, try to re-start, it just buzzes. However, if I wait for an hour or longer, it will usually re-start. When starting it up, it seems to act like a capacitor start motor when the capacitor is not working properly. However, this motor does not have a capacitor and there is no capacitor in-line that I can find. The tag on the motor states it is a thermally protected motor, is it overheating and the thermal switch is kicking in? If so, why would it buzz? Hum......I am stumped......
Any ideas before I buy a new motor?

same thing happened to mine (see post below on swamp buzzing)- for a while, before the motor gives up the ghost, it will turn over, but ultimatley, it will die. mine was working for 3 weeks this spring/summer, and then just up and died - all it did was buzz. so i bought a new motor the other day ($119 for a 1/2 horse at true value - not too bad), installed it, and that did the trick. it's nice and cool now, and none of that buzzing.

If the motor is running and then slows down and stops, then I would say either the motor has a bearing that is trying to seize up, or something in the motor is giving up when the motor gets hot.
Probably time to just grab a new one.

OK, thanks for your help!......I will opt for the new motor. Found a supplier via the internet of AO Smith 1/2 hp 2 speed new motor, it's $82 with free shipping, so will order the new motor and replace it. Luckily the swamp cooler is still working right now, as it's been 106-109 for five days now......and will only get hotter here in beutiful Las Vegas........

I'm here in Vegas also. Why order one on line, when you can go to lowes, home depot or nevada cooler pad?

If your new motor works for awhile then starts doing the same thing, in all likelihood you have bad bearings on the blower shaft. If they are not kept oiled, they wear out and the squirrel cage will not turn freely and bind up. This causes the motor to overheat and either shut down completely until it cools, or it will go into a very slow speed until it cools. Also, if the belt is too tight, or the adjustable pulley has been set to too big of a diameter, this can also cause the motor to overheat. Bottom line is your old motor may be fine.

Perfect advice herlongkid! My swamp cooler was working just fine when the motor seized, it was about 4yrs old. (i didn't realize there was oil ports to keep it lubed). So I ran to home depot and bought a new motor. I replaced the dead motor and oiled the entire blower unit. So when I turned it all on it ran for a few minutes and began to slow down, then finally to a stop and just buzzed. I checked the wiring, and the motor itself. both were not hot or smelled like they were burning.. So now I found this post and tried the advice.. To my surprise my adjustable pulley on the motor was set too large(all the way closed). I had to replace the old adjustable pulley because I couldn't get it off the dead motor. I didn't know that the adjusted diameter effected the motor operation.. Lesson learned. I opened up the new pulley making it smaller, readjusted the belt tension and now it works perfect. Thank you herlongkid.

You're welcome. Herlong is 70 miles from Reno. We had swamp coolers there too.

The motor must be mounted with the air vents downward. This is because the cooler air from below is taken in to cool the motor. If the ports are facing upward, the motor will pull in warmer air and continuously trip the thermal shutoff.






Tags: swamp, cooler, motor, stops, just, buzzes, adjustable pulley, before motor, bought motor, dead motor, down stops