Stepwise Balancing
1st pass, measure and record the airflow at all outlets.
2nd pass, starting with the highest, adjust the outlets with excess flow difference from the 1st pass to the low end of the design airflow 10% range. Then record the rest.
3rd pass, starting with the highest, adjust the outlets with excess flow difference from the 2nd pass to the low end of the design airflow 10% range. Then record the rest.
Three passes should get the system to within +/-10% of design airflow.
	Supply Outlet	Design Airflow	10% Range			1st Pass		2nd Pass		3rd Pass
1			58	-	72		+23%		+12%		OK
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