Do Fans get louder with time

greshoff · Post by **greshoff** » Thu Dec 04, 2003 10:38 am

Do fans get more noisy the more they are used. I installed a Panaflo 92mm fan with a fanmate controller, when I first installed it I could not hear it. Now I am aware of the sound of the fan in the background. It it the fan getting more noisy or my ears becomming more sensitive to computer noise.

If it is the fan can anything be done to make the fan quieter again.

lenny · Post by **lenny** » Thu Dec 04, 2003 10:52 am

Couple of things, one's a fact, another's a guess.

Over time you get a lot of dust accumulated inside the PC, especially around fans and heat sink fins. For some reason they seem to cling to the fan blades as well. Cleaning the dust away (I use canned air) seem to help with the noise. It definitely helps with cooling.

I'm also assuming that over time there's got to be a fair amount of wear on the moving parts. They should last a year or two at least though. There is another thread about oiling / lubricating fans. I think it's easier just to replace it.

kie · Post by **kie** » Thu Dec 04, 2003 11:53 am

I've lubed up old fans before and that resulted in them running quieter

greshoff · Post by **greshoff** » Thu Dec 04, 2003 12:06 pm

What type of oil does one use? A spray type?

kie · Post by **kie** » Thu Dec 04, 2003 12:15 pm

no - use a thick rotor grease if you have it
motor grease is a good substitute

avoid thin oils like wd-40

greshoff · Post by **greshoff** » Thu Dec 04, 2003 12:37 pm

Hi,

Does one need to dismantle the fan to apply the oil/grease?

kie · Post by **kie** » Thu Dec 04, 2003 1:35 pm

depends on the type of fan

the ones I greased up were had a rubber cap on the hub of the fan (it may be under a sticker)
simply remove the rubber cap, add grease, plug fan in to work the grease into the fan bearings, and then replace the cap

some fans don't have the rubber cap, and I'm not sure what to do with those

energy · Post by **energy** » Thu Dec 04, 2003 2:48 pm

The Panaflo have no rubber cap - they are a sealed fluid bearing motor and shouldnt get noticeably noisier over time unless you have a defective one, especially as Panaflo are top quality.

Silly question but maybe you've swapped some hardware after fitting the fan and maybe the new hardware is quieter so you can hear the fan more?

dukla2000 · Post by **dukla2000** » Fri Dec 05, 2003 1:02 am

greshoff wrote:It it the fan getting more noisy or my ears becomming more sensitive to computer noise.

Yes and yes.

You know you are a fully paid up member of "Silencers Anonymous" when each time you quieten 1 component the next noisiest item starts bugging you. This is also the explanation (IMHO) of how some folks post messages that say item X is dead silent: well yes, when I got my item X it was inaudible behind all the other noises. Now I have quietened all those other bits I now think my item X is the noisiest thing in my box.

But also, fans do get noisier with age. Dont have my library to hand, but Sunon or NMB or someone else explicitly point out their rated MTBF is also a factor of when the fan noise rises above some threshold. Also I have read somewhere that ball-bearing fans progressively get noisier through their life: sleeve bearings get slightly noisier as they run in, then the noise curve is flat(ish) until the end of life.

energy · Post by **energy** » Fri Dec 05, 2003 5:58 am

Fans do get noisier with age but a fluid bearing fan shouldnt be noticeably so.

silvervarg · Post by **silvervarg** » Fri Dec 05, 2003 6:46 am

Fans do get noisier with age but a fluid bearing fan shouldnt be noticeably so.

If I got things right all fans have 2 bearings (inner and outer bearing).
A 2-ball bearing fan has ball bearings in both palces.
A 1-ball bearing fan has ball bearing in one place and sleeve bearing the other.
A sleeve bearing fan has sleeve bearing on both places.
A fluid bearing fan has fluid bearing in one place and sleeve bearing on the other.

I the above is true the fan then I assume the fan should age similar to a sleeve bearing fan.

I don't think there is something like 2-fliud bearing fans.

Perhaps some fan expert can help us clear this out?

energy · Post by **energy** » Fri Dec 05, 2003 7:13 am

To the best of my knowlegde the entire assembly is a fluid bearing (which indeed is just a fancy sleeve bearing) but its design minimises metal to metal contact through a pressurised layer of oil so increased noise via ageing should be minimal.

scalar · Post by **scalar** » Sun Dec 07, 2003 5:38 am

With my panaflo L1A, it's not the hub or the blades getting louder, it's that durn clicking noise of the electromagnets turning on and off as it rotates. But really, this is to be expected as it ages and dust accumulates.

Increased drag means increasing torque is needed to keep spinning at the same speed, so those individual shock forces of the electromagnet pulses become clearer and louder as the mechanism "tightens up" from the extra drag on the rotors.

When it was new, everything glided along better, so those solid clicks of the electromagnets was buffered by the way the rotor kept up to speed so much more easily. Eventually I expect to be driven mad by that incessant clicking.. already I HAVE to turn off the PC before going to bed or I can hear the panaflo clicking away even with a blanket over my ears..

-Scalar

Rottweiler · Post by **Rottweiler** » Mon Dec 08, 2003 7:24 am

Thanks to inspiration from this thread, I just "fixed" a customer system that has an Athlon 1800+ fan by lubing it. The fan is dying so this is a stopgap, but it should hold until I can get a proper replacement (60x60x10).

I used fishing reel grease. This is a clear, lightweight grease. Considerably thicker than any oil, but far lighter than automotive "axle" grease.

The fan now sounds like a blowdryer instead of a chainsaw

fan-cy · Post by **fan-cy** » Tue Dec 09, 2003 5:33 pm

I have a similar problem. I quieted my CPU fan and bought the quiet power supply. The hard drive then drove me crazy, so I replaced it with a Seagate, soft mounted. Everything was great for awhile, but last week I started being bothered by the CPU fan again. I thought the fan was at fault, but as I was listening to it my refrigerator kicked on in the kitchen. While the fridge was running I couldn't hear the CPU fan at all, and then it occurred to me that I had never heard the fridge from my office.

My conclusions: First, my noise threshold has been lowered significantly, that's why the fan noise was apparent to me, and second, it's time to start the Silent Appliance Review website. Can I get Zalman to make me a refrigerator compressor??

fan-cy · Post by **fan-cy** » Tue Dec 09, 2003 5:56 pm

The fan does get noisier when it gets dirty. Dust on the blade leading edges will cause tones, a high frequency whine. Dust on the underside of the blade (the side of the fan the air is pushed to) will make it slightly less efficient, but I wouldn't expect this would be noticable. If the overall noise level is going up it's probably dust building up behind the fan, causing the fan to work harder against the increased blocking.

BTW, PC fans are typically brushless designs which means the only part that gets any mechanical wear is the bearing. Bearing life is measured in tens of thousands of hours so even if you never turn off your PC the fan motor should run for several years.

Post by **Ralf Hutter** » Wed Dec 10, 2003 7:07 am

fan-cy wrote:I have a similar problem. I quieted my CPU fan and bought the quiet power supply. The hard drive then drove me crazy, so I replaced it with a Seagate, soft mounted. Everything was great for awhile, but last week I started being bothered by the CPU fan again. I thought the fan was at fault, but as I was listening to it my refrigerator kicked on in the kitchen. While the fridge was running I couldn't hear the CPU fan at all, and then it occurred to me that I had never heard the fridge from my office.

My conclusions: First, my noise threshold has been lowered significantly, that's why the fan noise was apparent to me, and second, it's time to start the Silent Appliance Review website. Can I get Zalman to make me a refrigerator compressor??

You should repost this in the refirerator thread in the General forum. It would fit right in there.

Do Fans get louder with time

Do Fans get louder with time

Re: Do Fans get louder with time