NVR Getting Hot or Making Noise? Simple Fixes for Dahua, Hikvision & UNV Recorders
Is your security recorder sounding like a jet engine? Don’t ignore it. Here is how to fix the noise and prevent overheating before you lose data.
Your Network Video Recorder (NVR) is the heart of your security system. It works 24/7, processing video from multiple cameras and writing it to a hard drive. Like any hardworking computer, it generates heat.
However, it shouldn’t sound like a vacuum cleaner, nor should it be hot enough to fry an egg. Excessive noise and heat are early warning signs of hardware failure. If ignored, they can lead to a system crash—usually at the exact moment you need to retrieve footage.
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“Heat is the number one enemy of hard drives. A hot NVR is a failing NVR.”
In this guide, we troubleshoot the common causes of noisy and hot recorders for Dahua, Hikvision, and UNV (Uniview) systems, and offer simple fixes you can do yourself.
Problem 1: The Noise (Humming vs Grinding)
First, identify the sound. Not all noise is bad, but some noises are critical alerts.
The “Fan” Whir
Sound: A constant, high-pitched drone or air-rushing sound.
Cause: Small cooling fans spinning at high RPM. This is common in compact NVRs. If it gets louder over time, the fan bearings might be drying out or clogging with dust.
The “Hard Drive” Click
Sound: A rhythmic clicking, scratching, or clunking.
Cause: This is the “Click of Death.” It means the mechanical arm inside your hard drive is failing. Action Required: Backup your footage immediately and replace the drive.
The “Vibration” Hum
Sound: A low-frequency buzzing that stops when you put your hand on the case.
Cause: The metal case is vibrating against the shelf. Simple rubber feet or a mousepad under the NVR can fix this instantly.
Problem 2: Overheating
If your NVR feels hot to the touch, or if it is randomly restarting, it is likely overheating. This is often an environmental issue.
The “Stacking” Mistake
We see this all the time: The NVR is stacked on top of the modem, which is on top of a Foxtel box. Electronics need to breathe. Stacking them creates a heat sandwich that cooks everything.
The “Cupboard” Trap
Hiding the NVR in a linen cupboard or a tight TV unit might look neat, but without airflow, the hot air gets trapped. As the ambient temperature rises, the NVR’s fan works harder (more noise) but achieves less cooling.
Quick Troubleshooting Checklist
| Symptom | Likely Culprit | The Fix |
|---|---|---|
| Loud Whirring | Dusty Fan | Clean vents with compressed air |
| Clicking / Clunking | Failing Hard Drive | Replace HDD immediately |
| Hot Case / Reboots | Poor Ventilation | Move to open shelf / Add spacers |
| Vibrating Buzz | Loose Case / Feet | Add rubber isolation pads |
The Airflow Rule
The Danger Zone
- Enclosed Cabinet
- Stacked Devices
- Dusty Vents
- Sunlight Exposure
The Safe Zone
- Open Shelving
- 2-inch Clearance
- Clean Environment
- Cool Room
The Verdict: Maintenance Matters
An NVR is not a “set and forget” box. A little bit of maintenance—dusting the vents and ensuring it has room to breathe—can double its lifespan. If the noise persists, it might be time for a service.
Upgrade to Silence
If you are tired of the noise, consider upgrading to an Ajax NVR. They are designed with advanced passive cooling and high-quality components, making them virtually silent compared to older industrial recorders.
Don’t let a noisy box drive you crazy. Fix it, or replace it.
NVR dead or dying? Contact Sipko Security for a replacement or a system health check.
Frequently Asked Questions
Can I replace the fan myself?
Technically, yes. Most NVRs use standard 40mm or 80mm computer fans. However, opening the case will void your warranty. If your system is under warranty, contact your installer first.
How hot is too hot?
Most NVRs are designed to operate up to 40°C-50°C internal temperature. If the metal case is too hot to keep your hand on for more than a few seconds, it is definitely overheating and needs immediate ventilation.
Why is my new NVR noisy?
Some enterprise-grade NVRs (especially 16+ channel models) have powerful fans designed for server rooms, not living rooms. If you have a commercial unit in a home, the noise is likely normal for that model. We recommend placing these in a garage or laundry.
Official Government Sources & References
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Fire & Rescue NSW – Electrical Safety
Advice on preventing electrical fires caused by overheating appliances and poor ventilation.
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WorkSafe Victoria – Noise Hazards
Information on managing noise levels in workplaces, relevant for businesses with loud server equipment.
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Energy.gov.au – Appliance Efficiency
Tips on maintaining electronic appliances to ensure they run efficiently and don’t waste energy through overheating.
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ACMA – Equipment Standards
Standards for electronic equipment sold in Australia, ensuring they meet safety and interference requirements.
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EPA Victoria – Residential Noise
Guidelines on acceptable noise levels in residential areas, including noise from mechanical equipment.


