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LO-PRO IO&M
B51021-004
Installation
To prevent damage to the fan during shipping, motors 5 HP
and larger, and extremely heavy motors (cast iron or severe
duty) are shipped loose and must be field mounted by bolting
the motor on the motor mounting plate in the existing mount-
ing slots.
Damper Installation
If your fan is supplied with dampers, follow the directions
below. If your fan does not include dampers, proceed to
Belt
and Pulley Installation
.
1. Place the damper inside the curb or inside the duct work.
Ensure the damper will open freely for the correct direc-
tion of the airflow.
2. Secure to curb at the damper shelf.
3. Drill hole in the curb shelf for conduit needed for motor
wiring.
4. Operate the dampers manually to ensure the blades move
freely.
5. Install ventilator over curb.
Wall Installation
1. Position unit so that hinge on topcap is facing down.
Belt and Pulley Installation
Belt tension is determined by the sound of the belts when
the fan is first started. The belts will produce a loud squeal,
which dissipates after the fan is operating at full capacity. If
belt tension is too tight or too loose, lost efficiency and dam-
age can occur.
Do not change the pulley pitch diameter to change tension.
The change will result in a different fan speed.
1. Loosen the motor plate adjustment nuts on motor base
and move motor plate in order that the belts can easily slip
into the grooves on the pulleys. Never pry, roll, or force the
belts over the rim of the pulley.
2. Adjust the motor plate until proper tension is reached. For
proper tension, a deflection of approximately 1/4” per foot
of center distance should be obtained by firmly pressing
the belt. Refer to
Figure 1
.
3. Lock the motor plate adjustment nuts in place.
4. Ensure pulleys are properly aligned. Refer to
Figure 2
.
Tolerance
Center
Distance
Max.
Gap
Up thru 12” 1/16”
12” up
through 48 1/8”
Over 48
1/4”
OFFSET
ANGULAR
OFFSET/ANGULAR
A
W
X
Y
Z
B
CENTER
DISTANCE
(CD)
GAP
GAP
Pulley Alignment
Pulley alignment is adjusted by loos-
ening the motor pulley setscrew and by
moving the motor pulley on the motor
shaft.
Figure 2
indicates where to measure
the allowable gap for the drive
alignment tolerance. All contact points
(indicated by WXYZ) are to have a
cap less than the tolerance shown in
the table. When the pulleys are not the
same width, the allow-able gap must
be adjusted by half of the difference
in width.
Figure 3
illustrates using a carpenter’s square to
adjust the position of the motor pulley until the belt
Figure 3
is
parallel to the longer leg of the square.
Wiring Installation
Leave enough slack in the wiring to allow for motor move-
ment when adjusting belt tension. Some fractional motors
have to be removed in order to make the connection with the
terminal box at the end of the motor.
Refer to Wiring Diagrams, page 6.
NOTICE! Follow the wiring diagram in the discon-
nect switch and the wiring diagram provided with
the motor. Correctly label the circuit on the main
power box and always identify a closed switch to
promote safety (i.e., red tape over a closed switch).
Optional Diverter
1. Position diverter so that air flow is directed up.
2. Seal between diverter flange and unit side panel with RTV
400 silicone. (RTV Silicone is NOT supplied.)
3. Use screws provided to secure diverter to unit.
Optional Grease Terminator Installation
1. Attach hardware to drain hole in the diverter. See
Figure 4
.
2. Screw new canister into lid.
Conduit Nipple
Conduit Nipple
Diverter
Diverter
Terminator Lid
Terminator Lid
Sealing Nut
Sealing Nut
Terminator
Terminator
Terminator
Terminator
Terminator
Terminator
Roof Top Installation Shown
Roof Top Installation Shown
Figure 4
Figure 4
1 foot
1/4 inch
Figure 1
Figure 2