Installation manual

IM-487 Page 45
angle and the snubber neoprene bumper. However, in a "seis-
mic event," the snubber will limit movement of the spring
mounted fan assembly to .25" (6 mm) in any direction,
thereby helping to prevent the fan from being tossed about
and damaged, or causing damage.
When a seismic restraint is properly adjusted and the fan is
operating normally, the neoprene center bumper will be cen-
tered within the 2" (51 mm) diameter hole in the restrainer
angle, and the restrainer angle will be centered vertically
between the flanges of the neoprene center bumper. This
results in .25" (6 mm) clearance in all directions. When the
fan is turned off the restrainer angle may come to rest on the
neoprene center bumper.
Figure 53. Cross Section of Seismic Restraint
The seismic restraint is adjustable in all directions. Vertical
slots in the restrainer angle and horizontal slots in the blower
base allow the restrainer angle to be adjusted up and down
and back and forth. The neoprene center bumper is mounted
on a slotted hole allowing its adjustment in and out.
Removing the neoprene center bumper bolt allows removal,
disassembly, and replacement of the neoprene components.
Adjustment of Scroll Dampers
(RDS 800 Only)
Two sets of scroll dampers are provided in the housing of the
twin 15" x 6" supply fan to allow control of air volume to
each fan wheel. At the factory, these dampers are fully closed
unrestricting airflow. If fan paralleling occurs, correction can
be made by loosening the adjustment screws on top of the fan
housing and slightly lowering the rod until air distribution
between the fans is even. See Figure 54.
Figure 54. Scroll Damper Adjustment
F a n B a s e C h a n n e l
S n u b b e r R e s t r a i n e r A n g l e
A d j u s t U p o r D o w n
o r B a c k a n d F o r t h
S n u b b e r N e o p r e n e
B u m b e r
. 2 5 " ( 6 m m ) G a p
( F a n R u n n i n g )
A
d j u s t I n a n d O u t
S n u b b e r N e o p r e n e
B u m b e r
A d j u s t m e n t A s s e m b l y
S c r o l l D a m p e
r