Applies to: Reolink NVRs 

The function of the fan inside of Reolink NVR system is heat dissipation.

Considering the noise caused by the fan, Reolink had replaced the fan of new model 8 channel NVR system (RLN8-410-E/Hw. H3MB18/N3MB01) by the heat sink, which greatly reduced the noise from the working fan. Reolink will consider replacing the fan for all models NVR system by the heat sink step by step in the future soon. 

Normally, the sound of the fan is under the normal sound range.  If your NVR model is the old version and comes with a noisy fan, it's suggested to put the NVR system in the place with fewer activities, especially far from your bedroom. 

If the sound is still very loud and noisy, please use the Decibel Tester to test the sound range and report to Reolink support, they will offer you more suggestions.