Whining noise from S9 fan?

[ccgllc]

High-backpressure-tolerant many-blade fan designs are notorious for their high-pitched "whine" when running at high RPMs.

It's PROBABLY normal.

Concur that its normal.  That said, the screw torque or filter material may help you adjust it to something less annoying.

[ruinous]

Have you tried the filters on any 741, 821's from Canaan? They can whistle to although I find it more bearable than the s9 at max fan speeds.

Unfortunately only have experience with S3s, S4s, S7s, and S9s.  Thinking about dipping into 841s, but that is a different thread.

Roger that, a bit relevant to the whistle/wine but not an antminer.

I'll give it shot and update in another thread about the avalons as I was at Home Depot today and grabbed some duct filters. They seem pretty thick so I'll set it up when I have time to monitor temps for a couple hours with shop doors closed and just intake and exhaust fans on (only have 350 CFM in/out for my small mine).

[ruinous]

Well I added the filter to the s9 had a 10C change in moments which made me nervous to leave as I got ready to end the day. So I cut a piece in proportion to the tape I had to control the sound, now I have more air flow than previously and less whine/whistle. I think as well, when the really cooler months come again I might use these to filter the air, reducing dust and bring temps up. As s9 like to run warmer than s7 which seemed to like 60-70C for me.

Any thoughts on the filter causing a fire hazard if enough of the poly is pulled in over time? 

[ccgllc]

The ones I bought at Lowes were approximately 4" x 12" and no more than a 1/4" thick.  They were designed to be put into air duct floor registers.

Edit:  Found them https://www.lowes.com/pd/WEB-12-Pack-Green-and-White-Bag-Register-Vent-Filter/3122205

[ruinous]

Essentially that's what I purchased at HD. Not much in details on the packaging though.

[QuintLeo]

Well I added the filter to the s9 had a 10C change in moments which made me nervous to leave as I got ready to end the day. So I cut a piece in proportion to the tape I had to control the sound, now I have more air flow than previously and less whine/whistle. I think as well, when the really cooler months come again I might use these to filter the air, reducing dust and bring temps up. As s9 like to run warmer than s7 which seemed to like 60-70C for me.

Any thoughts on the filter causing a fire hazard if enough of the poly is pulled in over time? 

Put a fan guard between the fan and the filter material, jammed fan = significant probability of overheated and DEAD miner even if you don't get a fire (which isn't REAL high probability).

[ccgllc]

Put a fan guard between the fan and the filter material, jammed fan = significant probability of overheated and DEAD miner even if you don't get a fire (which isn't REAL high probability).

Don't all S9s come with a fan guard?  All of mine did.