Airflow for hard drives in 19" rack case

[breacH]

Hi there,

I'm new to the forum, but already found really helpful informations here.

I recently moved my stuff into a 19" rack cabinet.
Right now my NAS is still a Lian Li case with a custom how-swap cage and bezel that hold 3x120mm Noctua NF-A12 fans pushing air at 50% on 7 hard drives and 3 SSD. (see picture attached, old setup with other fans but you get the idea)
The case is just placed horizontally on a shelf.
Right now the drives are sitting at 35-37°C except these f****** WD RED 8TB drives that are in the 50-55°C range depending on the load...

I will soon move the hardware in a Inter-Tech 4U 4129-N case, to have a real rack mountable case and use the shelf for something else.
Due to the custom hot-swap cage i can have only the 3 Noctua in the middle of the new case, pulling air throught the drives.

I'm begining to doubt about airflow for the drives.. Will it be enough?
I have no experience in rack mountable case cooling. Any advice would be very appreciated.

Cheers!

 

[gb00s]

You will be fine I suppose. Maybe I'm totally dumb, but with the Inter-Tech 4U 4129-N you can either push or pull air through the disk trays. As the screenshot below shows, you can switch all the fans in the 3 locations, backplate, fan appliance in the middle, and right between front and disk tray.



You just have to decide which way to go for the airflow and you prefer positive (over)pressure (blue) or negative (under)pressure (red) in the case. Which way you want to go might be a dust decision as well. Anyway, be aware of the noise of the factory fans. I'm not mistaken they are not PWM regulated. But you can do it yourself. Also, get Noctuas if noise is a concern.

I prefer reduced pressure installations.

Mike

 

[EffrafaxOfWug]

Anyway, be aware of the noise of the factory fans. I'm not mistaken they are not PWM regulated. But you can do it yourself. Also, get Noctuas if noise is a concern.

Impossible to tell without a detailed picture of the fan backplane which isn't shown on the Inter-tech site, but the case internals and the fan wall look identical to my LogicCase SC-316 (a rebadged version of the Norco for the UK market) which came with a PWM-compatible fan backplane as detailed in my thread here.

Probably worth asking the vendor if it uses the same fan wall/backplane, in whcih case you'll be able to add aftermarket PWM fans.

 

[gb00s]

Impossible to tell without a detailed picture of the fan backplane which isn't shown on the Inter-tech site, but the case internals and the fan wall look identical to my LogicCase SC-316 (a rebadged version of the Norco for the UK market) which came with a PWM-compatible fan backplane as detailed in my thread here.

Probably worth asking the vendor if it uses the same fan wall/backplane, in whcih case you'll be able to add aftermarket PWM fans.

I remember a similar case (2U) that had the Molex connector as PCB setup. The stock fans are for sure 3pin fans. Why you would provide 3pin backplane fans (as the picture shows), but offer 4pin fans in the fan wall? I know some U2 Inter-Tech chassis have a Molex connector and a 4pin connector. But here, you might be able to connect, if a 3pin connector is there, 2x dupont cables to the motherboard and control after-market (Noctuas) 4pin PWM fans from the motherboard.

 

[i386]

I would always pull air through hdds cages/trays. Pushing requires a lot of static pressure...

 

[EffrafaxOfWug]

Why you would provide 3pin backplane fans (as the picture shows), but offer 4pin fans in the fan wall?

Price? The stock fans on my SC-316 were 3-pin as well - cheaper than PWM fans and most people won't care - but the fan backplane was all 4-pin connectors (the extra cost of 4 pins on the backplane will be pennies for hundreds of units).

 

[gb00s]

I would always pull air through hdds cages/trays. Pushing requires a lot of static pressure...

But in order to pull through the disk tray he has to switch the fans on the front and take away the dust filter I suppose. With a negative pressure setup (red), he would have a nice push/pull-setup ... push from the fan wall and pulling from the front fans.

Price? The stock fans on my SC-316 were 3-pin as well - cheaper than PWM fans and most people won't care - but the fan backplane was all 4-pin connectors (the extra cost of 4 pins on the backplane will be pennies for hundreds of units).

I meant 3pin fans on the backplate, not backplane. I'm sorry for the confusion.

 

[breacH]

Wow wow, i did not expect so many replies!
Thanks a lot.

You will be fine I suppose. Maybe I'm totally dumb, but with the Inter-Tech 4U 4129-N you can either push or pull air through the disk trays. As the screenshot below shows, you can switch all the fans in the 3 locations, backplate, fan appliance in the middle, and right between front and disk tray.

...

I prefer reduced pressure installations.

Mike

Due to the configuration of my custom HDD cages, i cant mount the 2 front fans. My goal was then to pull air through the disks from the fan wall.

Impossible to tell without a detailed picture of the fan backplane which isn't shown on the Inter-tech site, but the case internals and the fan wall look identical to my LogicCase SC-316 (a rebadged version of the Norco for the UK market) which came with a PWM-compatible fan backplane as detailed in my thread here.

Probably worth asking the vendor if it uses the same fan wall/backplane, in whcih case you'll be able to add aftermarket PWM fans.

View attachment 14383

I remember a similar case (2U) that had the Molex connector as PCB setup. The stock fans are for sure 3pin fans. Why you would provide 3pin backplane fans (as the picture shows), but offer 4pin fans in the fan wall? I know some U2 Inter-Tech chassis have a Molex connector and a 4pin connector. But here, you might be able to connect, if a 3pin connector is there, 2x dupont cables to the motherboard and control after-market (Noctuas) 4pin PWM fans from the motherboard.

The fan hub of the wall is appearently PWM. I'll check that when installing the fan and making some mods.

I would always pull air through hdds cages/trays. Pushing requires a lot of static pressure...

Okay so cooling could be even better when pulling air from the fan wall! From your experience, is it the case?

But in order to pull through the disk tray he has to switch the fans on the front and take away the dust filter I suppose. With a negative pressure setup (red), he would have a nice push/pull-setup ... push from the fan wall and pulling from the front fans.

I meant 3pin fans on the backplate, not backplane. I'm sorry for the confusion.

If i just remove the front fans i dont need to remove the filter which is in the main front cover. As i said i have no choice that using only the fan wall to pull air through the disks.

Along with the little case mods i will try to improve the airflow through my custom HDD cage, with some plastic covers etc.
I'll post pictures of the process.

Thanks again everyone for your replies!

 

[EffrafaxOfWug]

Okay so cooling could be even better when pulling air from the fan wall! From your experience, is it the case?

For my case, which doesn't have the two front fans but does have 16 drive bays, the three fans in the fan wall in a front -> back configuration work brilliantly for sucking air through the drive cages and out the perforations in the rear of the case (I'm also using 3x120mm PWM Noctuas). I don't even plug in the two rear fans since they're noisier than the fan wall and make negligible difference to temperatures. The gaps between drives on your case are slightly bigger by the looks of it, so your Noctuas shouldn't have any problem cooling the whole case adequately.

Don't try a back -> front with this configuration unless you're using high static pressure fans - very difficult to blow air through the hard drives, much better to create negative pressure behind them.

 

[gb00s]

Was wondering why you are all on a different setup and realized I missed this important part:

Due to the custom hot-swap cage i can have only the 3 Noctua in the middle of the new case, pulling air throught the drives.

Well, ...

 

[breacH]

For my case, which doesn't have the two front fans but does have 16 drive bays, the three fans in the fan wall in a front -> back configuration work brilliantly for sucking air through the drive cages and out the perforations in the rear of the case (I'm also using 3x120mm PWM Noctuas). I don't even plug in the two rear fans since they're noisier than the fan wall and make negligible difference to temperatures. The gaps between drives on your case are slightly bigger by the looks of it, so your Noctuas shouldn't have any problem cooling the whole case adequately.

Don't try a back -> front with this configuration unless you're using high static pressure fans - very difficult to blow air through the hard drives, much better to create negative pressure behind them.

Yes sure a back-front airflow would not be ideal here. Also due to the cabinet general airflow.
I will go with the setup i first thought of. I began some modding yesterday cutting of the grills of the fan wall and fan mount to maximise airflow and reduce turbulences.

 

[breacH]

Hello there.

I finally had some time to work on the server case.
Had to move my hard drive onto a small piece of wood in the other chassis, then i could move the home made drives bay into the new case.

Done so far:
- cutting the "star" shapes in the fan housings to improve airflow and reduce noise.
- drilled some new holes to attach the bay
- some wood work on the base of the bay
- a midplate made from PVC plastic to force the air to pass through the hard drive and not around the hard drive bay

Next:
- custom power cables for the drive bay
- custom fan cable for the 2x80mm
- moving the internals and hope for the best

 

[breacH]

Hello!

Had some time to finally finish the hardware transplantation and setup of the new case!
Here are some pictures.

The results in temperatures are awesome!
I went from 50-55°C to max 41-42°C on the WD RED 8TB drives.
With the same noise level!!

The whole rack is almost inaudible. I'm more than satisfied with that setup and my littles diy mods went really well.

Final thought: negative pressure in the hard drives bay IS THE WAY TO GO!

Thanks for all your comments and thoughts.

Cheers!