One of the recurrent issues with Hikvision NVR’s is the intolerable level of noise that it can produce, which may be ok if you place it a remote server room or attic in a thick cupboard but could cause real irritation if placed in a dining / bedroom, especially for people with higher sensitivity.
Hikvision’s NVRs (such as DS-7608NI-K2-8P) is fitted with two 40mm cooling fans and a loud PSU PSU (KSA-180S2) with a 12v 5A rail, a 52v 2.5A rail, which together produce a whole range of nasty metallic noises that can get under one’s skin.
In addition to just being loud, the fans operate at the maximum capacity at all times whether or nor it is required, rather than being temperature-controlled.
BIG DISCLAIMER HERE – before you start playing around with the NVR – make sure that you have the necessary tools (including a voltmeter), comfortable with electricity and really want to gamble with warranty. If you answered 'NO' to at least one of those questions – then the best thing to do is to look for a noise-cancellation case for your Hik NVR.
Step 1 - Fan replacement
The primary culprit responsible for the excessive noise generation is Hik’s 40mm fan. The replacement of it with a quality 80-120mm fan, which you can get from any good PC store, would do the job.
Make sure that the fan is properly fitted and oriented to supply enough air to the system, otherwise it may get damaged.
The standard Hik fan look like this:
Step 2 - Power Supply replacement
The cooling fans of most Hikvision NVRs are powered by (KSA-180S2) PSU over two voltage rails –12v 5A rail and 52v 2.5A (PoE) so make sure that you get corresponding AC adapters.
Cut the pigtail off the old PSU.
Cut off the pin plugs on the replacement AC adapters.
Connect the old PSU and the AC adapters via connector blocks (AKA Chock Blocks)
Mount and wire the fan (glue / weld / cable ties) to the bottom of the NVR (+ use fan gaskets) – I would recommend drilling holes through the bottom of the NVR’s housing where the holes for the old fan are.
If need be, cut a hole for the fan )or use the existing vents if possible)
Use noise absorption material to further silence your NRV if necessary
Finally, after the work is done, check the temperature stats (and keep it monitored for a few hours after you power it up) by logging into your NVR. - =>Configuration=>Storage Management=>Temperature.