All Reolink NVR system except for the new hardware version RLN8-410 comes with a fan, which is used for heat dissipation. If you want to replace the fan to solve some problems, please make sure that you make it carefully or refer to professional knowledge in case of damage to the NVR system.
Applies to: Reolink NVRs.
Normally, the sound of the fan is under the normal sound range. If the fan is noisy, it's suggested to put the NVR system in the place with fewer activities, especially far from your bedroom.
Considering the noise caused by the fan, Reolink replaced the fan of the new version RLN8-410 (with hardware version N2MB02/N3MB01/N7MB01/H3MB18) with the heat sink, which greatly reduced the noise from the working fan.
You might want to add or replace the fan in the Reolink NVRs. Pictures below show you the interface of the fan for different NVR systems.
Note: If the fan does not work, swap the positive and negative poles for a try.