Noise from Fans in room

Hi All,

After reading the HVAC chapter, just wondering are there any effective methods to reduce the noise from the HVAC/fans? ex: Is multiple small fans better than one large if to provide same amount air flow? Since they have smaller air speed for each one?


Hello @whuang -

You can utilize a sound damper in the ducts to reduce the noise from the HVAC fans. The longer the damper the more the sound is muffled, this is especially true of mechanical noise since the frequency is low and thus the wave lengths are longer.


An acoustic rule of thumb to remember is doubling the noise source increase the dB by 3. So I would assume multiple small fans would not help reduce the noise.

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