Argon Eon Hard Drive Temperature Fan Control

By default, the fan in the Argon Eon is triggered by CPU temperature. However, it’s possible to run an IO-intensive workload that gets the hard drives hot without stressing the CPU - particularly if you’ve jammed two 3.5" drives in there, as there isn’t much room for them to breathe.

I’ve popped a pull request across to Argon40 which adds hard drive temperature monitoring to the fan system. With that, the temperature triggers in your fan configuration will activate when either the CPU or the hottest-running hard drive in the Eon reaches the target - whichever comes first.

Should hopefully prevent any toasted-drive catastrophes!

If you’re looking to try it yourself before it’s merged (assuming it gets merged), my fork is here - you’ll need to install hddtemp, which you can do with sudo apt install hddtemp or by running the script in the tutorials/ directory.




First we would like to acknowledge the support and feedback of @NHHiker and @ghalfacree, which was very helpful as we continually improve on the Argon EON. Your input to this Forum is well appreciated by Argon40 and I am sure the community at large.

Regarding the Hard Disk Temperature, we did some tests and with the Raspberry Pi 4 in IDLE the CPU temp remains at 50C or below (even at our 30C ambient temp) and the mechanical drives were running between 40C-45C. At these temp ranges most manufacturers would rate their HDDs to work safely.

In light of the discussion in this FORUM we made the following changes:

(1) FAN Direction - Based on more recent test it is better for the FAN to blow outwards/upwards. Thus we recommend that Kickstarter Backers flip the FAN. Future buyers will receive their units blowing outwards.

(2) Argon Config - We have added a sub-menu for Users to SET the FAN Triggers based both on the HDD and CPU temperature. Thank you for suggesting this @ghalfacree .

We do not expect the EON case to cool the HDDs down to 30C as the EON’s cooling works like a system, wherein the RPI CPU temp will always factor in terms also in cooling the HDDs. But with ambient temperatures in the 25C or below we still expect the EON to run the HDDs in the low 40C and the RPI below 50C, which would not affect its long term performance of the attached devices.

Thanks to all for the suggestions concerning fan speed and direction. Decided to reverse the fan direction. Removed the drives (2x Seagate IronWolf, 4TB, SATA III HDD), then removed the fan and refitted it “upside-down”. Unfortunately, that caused the fan to stand more “proud” of the case and made it impossible to refit the drives safely. Any suggestions would be welcome.

Great idea, but querying the hdd temp spins them up, and that messes your APM levels/spindown timers…

My understanding is that optimal temperatures for hard drives are around 25-45C, and anything above will start to shorten the life of the drive. I only have a single WD Red hard drive, but most of the time it is running around 45C in the EON, which is right at the top of that limit. I program my fan to come on at 45C. When it does come on, of course, it’s noisy.

Seems to me that the design of the EON is probably best running 2.5" drives, that are both cooler, quieter and draw less power.

It’s a little scary, but you can get the 3.5" drives back in with the fan flipped over (assuming they’re the same dimensions as WD Gold 4TB drives). I tilted mine in, very carefully, and nothing broke.

I’m really starting to agree that 2.5" SSDs are the way to go with this thing, though. The fan combined with the lack of ventilation makes it unsuitable for being on my desk, and I can’t put it in my office closet for Reasons.

Either that, or I need to find someone who can cut vent strips and some fan mount screws into the plastic sides. I wouldn’t mind mounting some 5V fans to the side panels and powering them off the USB 2 ports.

Actually look at the back plate… that can come out. Mill the groves through and mount a 120 or 140mm fan on that side.

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My unit, purchased from Amazon and received in late June, has a downward blowing fan. To make matters worse, the fan does not shut off, no matter what settings I choose in argon-config, and no matter how low the CPU or HDD TEMPS…

Do I have a faulty unit? After tinkering for a days, it’s getting very hard to justify keeping it.

  1. Fan blows down by default install, to fix you have to swap it yourself
  2. Fan will run based off of the temperatures selected in:

Note the defaults will run the fan at 30% if the temp is higher than 35 degrees C,
might want to check the HDD temps.

If it were my setup I would change the 35=30 to 40=25, then restart the service (or reboot).

Sorry for one more question: Would it be possible to extend the functionality of the hdd part of the script a bit, so that it checks:
If the hdd is in sleep mode - no temp check will be done, therefore not waking up the disks
If the hdd is active, a temp check will be done and the triggers might start the fan

Would something like that be possible?

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Some hard drives come out of sleep mode when you ask it if it is in sleep mode… :frowning:

I’m bought an EON as a file server. After all sorts of disappointments with Pi OS and OMV6 I resorted to HAOS as my other machine was working fine running it was quietly working as I wanted it to in the background.

The Fan Control doesn’t work for me on HAOS despite fiddling with the Argon One script so I just pulled the plug on the Fan and found the CPU Temperature levels out at about 50DegC. Even when forcing the RPi to work a bit harder it raises to 55DegC then drops back down to around 50 again thanks to that big heat sink.

I checked the operating Temperatures of the RPi 4 and the two SSD I have fitted and can’t say I’m too worried as it is at the moment:

RPi 4B
CPU Temp 80 DegC max then throttles back

Samsung EVO:
Operating Temperature is 0 - 70 ℃
Critical temp is 85 °C

WD Green
Operating Range is 0-60C

Hi, I just wanted to share my experience. I finally setup my Eon and the fan noise was driving me crazy. I just installed the updated scripts from NHHiker and I am finally overjoyed to get some relief. I have 2x3.5" WD NAS drives and 2x2.5 Seagate Barracudas. I also have a 500gb USB/NVME (/dev/sdb) inside, so… yes it’s full and hot.

I bought this USB-powered fan off of Amazon with a flat top and legs to blow air upwards (plugged into a UBS 2.0 port on the EON. Here are my current temps.

argon-status --cooling

CPU Temperature:
C             F
27.74         81.94

Storage Temperature:
device        C             F
sda           35.0          95.0
sdb           31.0          87.8
sdc           33.0          91.4
sdd           33.0          91.4
sde           34.0          93.2

Fan Speed:

Temperature Settings Table:
Temperature   40.0          44.0          46.0          48.0          50.0          52.0          54.0          55.0          60.0          65.0
HDD fanspeed  25            30            35            40            50            55            60                          100
CPU fanspeed                                                                                                    30            55            100

Much happier now, notice the main fan is off at the moment. The bottom fan is 120mm, not silent, but much more quiet. I have no affiliation with this fan, but here is the link if anyone is interested. The EON is on top of it.

120mm USB Fan

I hope this helps someone, especially if you have your NAS full with 3.5 drives.

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EON Temp with old script, just as I started with the fan. (Internal case fan blasting very loudly)

EON Temp with the new script and after reboot. (Internal case fan at zero RPM!)

EON sitting on the fan (plugged into USB 2.0)

Excuse the temp setup, as my wife would kill me if I left it there. :smiley:


There is an extra add-on you need to install in Home Assistant or HAOS to get fan control.

TY for your post - Tried all version of that add-on and that doesn’t work either. I talked to the guy who devised the Add-on and he would need an actual EON sent to him in Belgium to work out how to code it so it would work.

Hello all!
I’ve just bought argon eon case too and I’m so exited to use it. As I’ve put it all together I want to give feedback and some recommendations to improve cooling.
I agree with AhnFire using fan to blow from the bottom to have air flow through and flipping fan to blow upwards makes more sense. My main concern is that air should get in from bottom and be exhausted from top to ensure cold air constantly flow through all components and take heat out away. I’m sure Argon team are working on creating new case for raspberry pi 5 and I want to suggest improvements in your case design.

As you can see in this pictures I used a Gorilla tape to separate inner chamber before fan and “exhaust” chamber after fan. Fan blowing upwards fyi. This way instead of inefficiently circulating air inside where, according to my opinion, about 20% of air is escaping and 80% is circulated, with my exhaust chamber separation 100% of hot air is being pushed out and cold air is coming in from the bottom intake.
Here is result of my work:

root@omv:~# cat /etc/argoneon.conf
temperature = C
debug = Y

screenduration = 10
screensaver = 60
screenlist = clock cpu storage bandwidth ram temp ip
enabled = Y

45.0 = 25
50.0 = 30
55.0 = 55
60.0 = 100

38.0 = 25
40.0 = 50
44.0 = 60
46.0 = 80
48.0 = 90
50.0 = 100

root@omv:~# argon-status -t --hddtemp -f

Fan Speed:

CPU Temperature:
C             F
36.02         96.84

Storage Temperature:
device        C             F
sda           36.0          96.8
sdb           31.0          87.8

My /dev/sda is m.2 PCIe NVME SSD Kingston A1000 240 Gb on (NVMe to USB Adapter M.2 SSD to USB 3.1 Type a Card with RTL9210 D Enclosur Q8M8) and my /dev/sdb is 3.5 Seagate NAS 4Gb HDD 7500 Rpm. I’ve flashed Debian 11 to SSD using pi imager and installed it to Argon EON case together with HDD wich already had some filesystem with data. So I had all covers closed and installed openmediavault and now watching movies from minidlna. Throughout of all time fan kicks in for about 40 sec with interval of 1-2 mins with speed of 25%. It’s not noisy. My CPU never exceeds 35C and neither HDD nor SSD exceed 37C. My room temperature is 73F or 22.8C I’m sure I can have second 3.5 HDD and it will not make any issues.
So Argon designers for raspberry pi 5 please have some “exhaust” chamber separation after fan so 100% of air is pushed out removing heat away and not circulated inside accumulating heat.

my second advice is please move internal USB 3.0 port away from back wall and place it longitudinally as in this picture:

This way we will be able to attach heat sync and have better airflow. I hope with raspberry pi 5 having PCIe interface we no longer will use USB bridge. You could instead of USB 3.0 port build m.2 connector instead standing upright longitudinally as shown in picture. So we could use heat sync.

My third advice. I’m sure you will take advantage of raspberry pi PCIe interface you might reduce 2 HAT boards to 1? And please make more space between raspberry pi board and your board so we could have some heat syncs to those chips on argon motherboard as they getting really hot too.

I wander if you will continue passive cooling or will you move fan to bottom to blow in on to CPU heat sync. This way we will have 100% air in and out from top exhausts. Same idea as AhnFire using.

Please let me know what do you think?

My best regards.

P.S. Thank to NHHiker! I really appreciate your latest script from !


You might consider changing:

screenduration = 60
screensaver = 30

Screen saver does not run if the duration “screensaver” value is greater then screenduration.

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