Make Your NAS Quiet in 2026: Step-by-Step Guide

A NAS sitting in a living room or office is mostly audible for three reasons: the system fans, the hard drives (spinning platters and head movement) and vibrations passed on to the furniture. This guide uses the Synology DS923+ as its example. We start with the risk-free settings in DSM and around the NAS. Then we look at replacing the fans, with its real constraints.

First, a common mistake to correct: the DS923+ uses two 92 × 92 mm system fans, according to retailer spec sheets (Galaxus, Wibi). A Noctua NF-A14 PWM is a 140 mm fan. It does not fit in the DS923+ and is not suitable for this NAS. It suits an enclosure with a 140 mm mounting position, such as a self-built NAS in a PC case. For a DS923+, you need a 92 mm fan with the same thickness as the original.

Another important point: opening the enclosure to fit non-Synology parts is not something Synology approves. It may void your warranty. If your NAS is still under warranty, stick to the software and environmental changes (steps 1 to 3) or contact Synology support.

Prerequisites

• A Synology DS923+ (or another model: adapt the dimensions and check its documentation) running DSM 7.x.
• A DSM administrator account and a computer on the same local network as the NAS.
• For the replacement (optional): two 92 mm fans whose thickness and connector match the originals, a Phillips screwdriver, an anti-static wrist strap, something to label the drives with and a phone to take photos.
• A recent backup of your data (see the link at the end of this article). Hardware work always carries some risk.

Step-by-step installation

Step 1: Measure the starting point

Before changing anything, write down the current temperatures so you can compare later. In DSM, the system temperature is shown in Info Center > General. Each drive’s temperature is in Storage Manager > HDD/SSD.

If you prefer the command line, enable SSH temporarily (Control Panel > Terminal & SNMP > Enable SSH service). Connect from your local network only, then list the drives:

ssh your_admin@192.168.1.50
ls /dev/sata* /dev/sd? 2>/dev/null

Then read each drive’s temperature. On DSM 7, internal drives usually show up as /dev/sata1, /dev/sata2… Use the names returned by the previous command.

for d in /dev/sata1 /dev/sata2 /dev/sata3 /dev/sata4; do
  echo "== $d"; sudo smartctl -A "$d" | grep -i temperature
done

Check: each drive returns a Temperature_Celsius line (or equivalent) with a value. Note these values along with the time and what the NAS was doing (idle, or running a backup).

Step 2: Choose the fan mode in DSM

DSM does not offer a custom fan curve. It offers preset modes, under Control Panel > Hardware & Power > General > Fan Speed Mode. According to Synology’s documentation, the available modes depend on the model and its configuration: Full-Speed, Cool, Quiet and, on some models, Low-Power. Adding a network card may disable some modes to ensure proper cooling.

1. Select Quiet Mode (or Low-Power if it is offered).
2. Click Apply.

# Check after 24 h of normal use (on the NAS, over SSH)
for d in /dev/sata1 /dev/sata2 /dev/sata3 /dev/sata4; do
  echo "== $d"; sudo smartctl -A "$d" | grep -i temperature
done

Check: compare with the step 1 readings, under the same activity conditions. If drive temperatures rise noticeably, switch back to Cool mode. The temperature limits to respect are in your drives’ datasheet.

Step 3: Reduce drive noise and vibration

On a NAS, the hard drives are often louder than the fans.

• HDD hibernation: Control Panel > Hardware & Power > HDD Hibernation. Choose an idle delay. Services that access the volumes constantly (indexing, containers, logs) can keep the drives from spinning down.
• Placement: put the NAS on a heavy, stable surface, not on hollow furniture that acts as a sound box. Leave space behind it for the exhaust air.
• Isolation: rubber or foam pads under the NAS reduce vibration transfer. Never block the air intakes.

# Spot frequent disk access that prevents hibernation (DSM, SSH)
sudo tail -n 50 /var/log/messages

Check: once the chosen idle period has passed, the drives stop making spinning noise. The NAS status LED shows hibernation, as described in your model’s hardware guide.

Step 4: (Optional, out of warranty) Choose replacement fans

Only go ahead with this step if steps 1 to 3 are not enough and you accept the risk of losing the warranty. Synology also sells original fans as spare parts for some models (the Spare Parts section of the Synology website). That is the safest option if a fan has become noisy because it is worn out.

What to check before buying a third-party fan:

• Size: 92 × 92 mm for the DS923+. Measure the thickness of the original fan: a thicker model may not fit.
• Connector: photograph the original fan’s connector and the board header. Count the pins and look at the keying. Don’t buy anything until you have confirmed compatibility.
• Minimum speed: DSM monitors fan rotation. A fan whose minimum speed is too low can trigger a “fan failure” alert (beep and notification) even though it works. This is the main trap with “ultra-quiet” models.

# Before buying: check for existing fan alerts
sudo grep -i fan /var/log/messages | tail -n 20

Check: the command should return no recent fan errors. If it does, fix that problem first: a faulty original fan is covered by the warranty.

Step 5: (Optional) Disassemble and replace the fans

1. Shut down the NAS from DSM (user menu at the top right > Shut down), then unplug the power and network cables.
2. Label each drive with its bay number, then remove the trays. You will need to put them back in exactly the same place.
3. Remove the Phillips screws holding the shell (at the back or on the side, depending on the model; see the hardware installation guide) and slide the shell off carefully.
4. Photograph the fan layout, the cable routing and the airflow direction. An arrow is moulded on the frame. On the DS923+, the rear fans push hot air out of the enclosure, and air comes in at the front through the drive bays.
5. Unplug one fan, remove it, then fit the new one facing the same way (airflow arrow pointing outwards, like the original). Plug it into the same connector. Repeat for the second fan.
6. Keep the cables clear of the blades, put the shell back, screw it in, then return each drive to its own bay.

# After reboot: does DSM respond? (from a PC on the local network)
curl -kI https://192.168.1.50:5001

Check: the command returns an HTTP header (for example HTTP/1.1 200), which shows that DSM is answering on its default HTTPS port (5001; 5000 for HTTP). In Storage Manager, all drives are present and the pool is Healthy.

Step 6: Validate cooling after the replacement

# Fan alerts since reboot
sudo grep -i fan /var/log/messages | tail -n 20
# Drive temperatures
for d in /dev/sata1 /dev/sata2 /dev/sata3 /dev/sata4; do
  echo "== $d"; sudo smartctl -A "$d" | grep -i temperature
done

Check: no new fan alerts in the logs or in Log Center, and temperatures close to the step 1 readings under the same conditions. Repeat the check during a heavy task (backup, data scrubbing). If you get a “fan failure” alert, switch to Cool mode: a faster rotation often clears it. If it persists, put the original fans back.

Verification checks

• Info Center > General: the system temperature is stable.
• Storage Manager: the pool is healthy and all drives are detected.
• Log Center: no fan-related entries.
• In the chosen mode, drive temperatures under load stay within their datasheet limits.

Security and best practices

• Always unplug the power before opening the enclosure and wear an anti-static wrist strap.
• Disable SSH once you have finished the checks (Control Panel > Terminal & SNMP). Never expose SSH or the DSM interface (ports 5000/5001) to the Internet through port forwarding. For remote access, use a VPN.
• Keep an up-to-date backup before any hardware work.
• Don’t block the air intakes to gain silence: a drive that runs hot wears out faster.

Troubleshooting common errors

Error: “fan failure” alert after the replacement

Cause: the new fan’s speed is too low for DSM, or the connector is not seated properly. Fix: check the connection and switch to Cool mode. If the alert continues, put the original fans back.

Error: a drive or the pool is “degraded” after reassembly

Cause: a drive is not pushed in fully or is in the wrong bay. Fix: shut down the NAS, return each drive to its original bay according to your labels, then check Storage Manager.

Error: the noise is still high

Cause: the noise comes from the drives or vibrations, not the fans. Fix: apply step 3 (hibernation, stable surface, pads).

Error: the “Quiet Mode” option is missing

Cause: the model or an expansion card limits the available modes. Fix: check your model’s specifications in the Synology Download Center.

FAQ

Can I fit a Noctua NF-A14 PWM in a DS923+?

No. The NF-A14 is 140 mm, and the DS923+ takes 92 mm fans. The NF-A14 PWM only suits an enclosure with 140 mm mounting positions.

Does replacing the fans void the warranty?

Probably: Synology does not approve modifications made with third-party parts. Before doing anything, check the warranty terms for your model or contact support.

Can I set the fan speed to an exact percentage?

Not with DSM, which only offers the preset modes from step 2.

What is the most effective option without opening the NAS?

Combine Quiet mode, HDD hibernation and a stable surface that damps vibration.

Read also

• Sauvegarder son nas sur un disque externe
• Ajouter un cache ssd nvme a son nas
• Nas silencieux salon chambre