o
peraTIon
G
uIdelInes
www.DaikinApplied.com 31
IM 777-18 • SKYLINE OUTDOOR AIR HANDLER
VFD Setup
Fans ordered with VFDs that were factory installed are setup
and tested prior to shipment. Prior to starting the fan(s), double
check the VFD settings according to the recommendations in
the VFD manual.
Once the correct VFD settings are verified, the fans should be
run through a sweep of the full range of operating speeds that
are expected to check for any vibration issues. If any areas
of concern are located, it is recommended to lock out those
frequencies using the VFD (see lock out frequencies or skip
frequencies in the VFD manual). This will ensure that the fans
will never operate continuously at those points, but will rather
pass through them to get to the desired points of operation.
Fan Startup
for proper fan rotation.
Observe the rotation. If the fan operates backward, reverse two
legs of the three-phase motor connections.
NOTE:
Variable pitch fan drives usually are provided for
operation in the mid-speed adjustment range.
However, the drives usually ship with the adjustment
opened up for minimum fan speed. Adjust the drives
for the proper airflow.
After the First 48 Hours of Operation
1. Disconnect and lock electrical power source.
2. Check tightness of all bearing, wheel, and sheave
.
3. Recheck belt tension and adjust if necessary. Belts that
are tensioned sufficiently to slip one to two seconds at
startup perform satisfactorily, extending life and reducing
vibration. If re-tensioning is necessary, be certain to
retain sheave alignment.
Fan Wheel Alignment
Figure 57: Wheel-to-Inlet Tunnel Relationship—Airfoil Type
Fan Wheels (Housed)
Table 7: Wheel-to-Inlet Funnel Relationship—Airfoil Type
Diameter – in .
A
in . (mm)
B
in . (mm)
Unit sizes 003 to 035
13.22
4.56 (116)
0.21 (5.33)
14.56
5.06 (129)
0.21 (5.33)
16.18
5.62 (143)
0.21 (5.33)
17.69
6.90 (175)
0.22 (5.59)
21.56
7.59 (193)
0.24 (6.10)
24.00
8.45 (215)
0.23 (5.84)
Unit sizes 040 to 090
20.00
7.19 (183)
0.31 (7.87)
22.25
7.69 (195)
0.33 (8.38)
24.50
8.56 (217)
0.31 (7.87)
27.00
9.47 (241)
0.63 (16.00)
30.00
10.47 (266)
0.39 (9.91)
33.00
11.75 (298)
0.38 (9.65)
36.50
12.78 (325)
0.38 (9.65)
40.25
14.31 (363)
0.50 (12.70)
Note:
1. To obtain rated air performance, dimensional relationship must beheld.
2. To obtain dimension A, loosen setscrews in wheel hub(s), shifting wheel(s) axially as
needed, and retightening setscrews.
3. To obtain dimension B, loosen screw and washer fasteners around periphery of
funnel(s), shifting funnel radially as required, and re-torquing fasteners.
Figure 58: Wheel-to-Inlet Funnel Relationship—Forward
Curved Type Fan Wheels
