how ling do your ventalstion fans typically last

[B-Rye-oNeR]

My fan recently crapped out after about 7 months of moderate use, how long do yours usually last? I got the cheepest one from grainger, like 80 bux, but I got the step up this time.

[Icarus]

Do you have it hooked up to a rheostat (variable resistor) by any chance? As far as I understand, unless they specifically are built for running at multiple speeds, it's hard on the motor.

Another thing to look at, are you using the fan to suck, or are you using the fan to blow? Cause they are much better at sucking than blowing. What I mean is, do you have it connected to a length of duct work? On which end? Does it have to suck the air through the duct work (so it's located at the end of the run, right at the exhaust exit), or does it try to blow it through the duct work (so it's close to you, and far away from the exhaust exit). The second option will be harder on it.

One last thing, if you are using ducting, what size are you using, is it smooth or corrugated, and does it have any bends? If you have to use ducting, the optimal type is going to be the same size to just slightly smaller than the fan, smooth walled, and with no bends. Small duct size, non-smooth walls and bends in your ducting will all contribute to higher static pressure and turbulence in the flow of air. All of those things are hard on the motor.

Think of it this way. Lets say you have a mouth full of water, and you have to ways to get it out. You can either use one of those straws that they use to stir coffee, or you can use a normal fountain soda type straw. Sure, both will be able to move water, but to move the same amount of water using the coffee stirrer straw, you're either going to have to put more pressure behind it, or you're going to have to use the same pressure, and let it take longer. Now remember your fan doesn't have a brain, so it's just trying to run at the speed that it's set to run. So anything you do that causes an impediment to its ability to move air is going to translate to more stress on it's motor while it tries to move the air.

Same goes for sucking instead of blowing. Lets say someone gives you a pint of beer and two straws, the same ones we mentioned before. Which is going to be easier to suck through. You can move the same amount of beer through either straw, but to move it though in the same amount of time means that you're going to have to be sucking a whole lot harder on the small straw than you would on the large one. (but of course, you wouldn't be caught dead drinking your beer through a straw, right?)

Sorry if this sounds kind of rambling, people keep on coming in to talk to me while I type this, and I've lost my train of thought a few times.

Hope that maybe some of that helped.

As another side note, most of the gable fans they carry at Home Despot come with at least a five year warranty. If Grainger won't warranty that fan for you, consider picking one up there.

[Dom]

Is your torch directly in front of the fan? When I got my mirage, it burned out the motor real fast. I realized I had all the heat of the torch pointed right at the motor.

[barefoot stash]

We've got the home depot attic vent fans mounted directly outside (no ducting) and I'd say they last about a year to year and a half. The heat isn't so much the problem as the dust/debris that collect. I try to be diligent and bust out the compressed air and clean them out, which does help a lot. I've looked and the dead motors and I swear it might just be the little starter that goes. Does anyone have a source for these? Seems like an easy fix if it worked.

[Sometime79]

Icarus does have valid points but first and foremost is the Fan vs. electrical current. I have run two 2500 cfm fans both on Rheostats for over four years. Rheostats do not burn a motor so much as screw up Amps versus Volts on your motor OHMs Baby OHMs. Even more important than a good Rheostat is a good gauge electrical wire at an adequate length. Resistance and Impedance! Diagram your set-up and we can help you not die so early. Resist and Impede Resist and Impede.

[elad65]

What do you mean by crapped out, electrically or mechanically (bearings)?

Something to consider is does the bearings/shaft have oil holes. Some motors have sealed bearing that you can not lubricate some have bearings you can. Check for oil hole, and maybe a few drops of 3-1 oil.

Fans/blowers that have oil holes on motor should be oiled once a year (or so). It's a maintenance thing.

Elad

[B-Rye-oNeR]

there appears to be some corrosion from the torch being pointed directly at it, I believe it's from the heat or dust and debris being pulled through, or maybe it got wet somehow... might try to put them up higher up in the windows,

[B-Rye-oNeR]

I put a blast shield in front of the fan motor, hopefully it helps