5326602-XIM-B-1019
42
Johnson Controls Ducted Systems
5.
Select the correct blower performance table for the unit
from Tables 22 and 23. Tables are presented for side and
down flow configuration.
6.
Determine the unit Measured CFM from the Blower
Performance Table, External Static Pressure and the
number of turns the variable motor sheave is open.
7.
To adjust Measured CFM to Required CFM, see SUPPLY
AIR DRIVE ADJUSTMENT.
8.
After reading has been obtained, remove the tubes and
seal holes.
9.
Tighten blower pulley and motor sheave set screws after
any adjustments. Re-check set screws after 10-12 hrs. run
time is recommended.
NOTE:
With the addition of field installed accessories repeat
this procedure.
Figure 29: Dry Coil Delta P 50” Cabinet
Failure to properly adjust the total system air quantity
can result in extensive blower damage.
ZF 150
ZF 120
Airflow (CFM)
Dry Coil Delta P
(IWG)
ZF120-150 50” CABINET, 50 HZ UNITS
INDOOR COIL PRESSURE DROP VS AIRFLOW
1500
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
2000
2500
3000
3500
4000
4500
5000
5500
6000
6500
7000
