Oxygen 8 SERENA - Airflow Balancing in Duct

Installation Manual Serena Series
7.3 Airflow Balancing in Duct
Notes:
For balancing, the extension box cover plate is provided
with 3 holes on the supply side and 3 holes on the exhaust
side.
Do not use the Pitot tube to open holes in the insulation as
it may block/damage the Pitot tube.
Take 3 readings on each hole and average all 9 readings
for supply and same for exhaust.
After balancing is finished, plug all six holes with the plastic
plugs provided with the unit.
Notes:
To take more accurate readings, use option #1 if possible.
The accuracy of the flow reading will be aected by how close to any elbows or bends the readings are taken. Accuracy can be
increased by taking an average of multiple readings as outlined in section 5.2.
∆P" CFM
6" 7"
0.004 0.002 50
0.006 0.003 60
0.008 0.004 70
0.010 0.006 80
0.013 0.007 90
0.016 0.009 100
0.020 0.011 110
0.023 0.013 120
0.027 0.015 130
Duct Diam. Cross Sect. Area
6" 0.196 sq. ft.
7" 0.267 sq. ft.
∆ P" = Velocity Pressure in inches
CFM = Opening / Cross-Sectional Area (sq.ft.) x velocity (FPM)
option #2