I have a PR4100 and upgraded my hard drives. The cooling fan works, but the drives become hot and sometimes shut down due to heat. While cleaning out the case for dust, I realized the problem is not the fan, per se, but the case design:
The bonehead who approved this case didn’t realize that the drives themselves would be blocking the airflow to the fan. If you see my dissection above, you’ll realized that only part of 3 slits are pulling air through the case. The vent holes in the front of the case are blocked by the hard drive case themselves, which sets just a few mm’s from the grillwork. The slots in the back are blocked by the drive casing. The slots on the upper back are partially blocked. So, I’m not sure if there is ‘adequate’ spacing for heat dissipation, let alone airflow. I’m wondering if I may need to modify the case somehow to increase air flow. I would like to hear other’s advice on how to improve the cooling.
Did this just start happening recently? How long have you had your 4100?
Does the fan spool up when you first power on and then settle down after a few minutes?
What kind of load are you putting on it when it “overheats”? Does it prompt an alert?
What drives do you have in it?
I have an older EX4. It’s a 4x2tb using Seagate NAS drives (CMR) in Raid 5. I never hear the fan except when first booting. Disk temps when not actively using hover in the low 30C. I just uploaded 30 gigs of VMs and drive temps peaked around 37C. The front panel display shows 42C/107F.
The slots on yours seem to align with the gaps between the disks.
The WD My Cloud PR4100 tends to run warm when fitted with higher-capacity or 7200 RPM drives because the airflow inside the chassis is tight. The front intake is partially restricted by the drive trays, so most of the cooling depends on the rear exhaust fan. When hotter drives are installed, that limited airflow can push temperatures high enough to cause throttling or shutdowns. Before modifying the case, check the SMART drive temperatures, make sure the unit has good clearance around it, clean out any dust, and consider upgrading the rear fan to a higher-airflow model. In many situations, improving ventilation and exhaust airflow is enough to resolve the heat issue without cutting into the enclosure.
