Fans by Fantech Electronic Catalogue

P-17

2016

INSTALLATION DO’S AND DON’TS

Figure 4.14. - Changing direction of airflow

Don't use sharp bends or takeoffs.

Do use sweeping bends and takeoffs. Use long chord turning

vanes where possible. Keep velocities low to reduce airflow

generated noise levels.

Don’t select a silencer with high attenuation and low percentage

open area without checking the airflow generated noise level.

Do check silencer airflow generated noise levels when these

conditions occur. If airflow generated noise is too high, try using

a longer silencer with a larger open area to get the same

attenuation at a lesser airflow generated noise, or acoustically

treat the duct after the silencer.

As a general rule of thumb, a pressure drop of 30 Pa should

limit the airflow generated noise of a silencer to an acceptable

amount in normal office areas.

4.0 NOISE CONTROL (Cont.)

Figure 4.13. - Airflow generated noise from silencers