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Pre Start-Up Checks
Before Fan Installation
Before starting up or operating fan, check all fasteners
for tightness. In particular, check the cap screws in
wheel bushing.
Wheel Alignment
1. Rotate the fan wheel by hand and assure no parts
are rubbing. The wheel should rotate freely and
be aligned as shown in Figure 1. Wheel position is
preset and the unit is tested at the factory.
2. Movement may occur during shipment, and
realignment may be necessary.
Radial Gap - If necessary, adjust inlet cone position
such that the radial gap between the wheel cone and
inlet cone is evenly distributed around the wheel.
Alignment - If necessary, adjust wheel position
by loosening the wheel hub (see Tapered Bushing
Installation and Removal on page 9) from the motor
shaft so that a straight edge held tight to the wheel
cone just touches the inlet cone. Refer to Figure 1.
Wheel Cone
Gap
Inlet Cone
Figure 1
Recommended Fastener Torque
Size
Type
Self-Drilling Sheet
#12
Metal Screw
Hex Bolt/Thumb
1/4 in.
Screw
1/4 in. x 20
Cap Screw
1/4 in. x 20
Cap Screw
5/16 in.
Semi-Gimlet Bolt 132 (11) 144 (12) Fan Construction
Serrated Flange
3/8 in.
Bolt/Nut
Serrated Flange
1/2 in.
Bolt/Nut
4
Rooftop Supply Mixed Flow Fans
Straight Edge
Recommended
Torque in∙lb (ft∙lb)
Application
Min.
Max.
25 (2)
30 (2.5)
Outdoor Panels
Ductwork and
96 (8)
108 (9)
Accessory
Mounting
QT Bushing
120 (10) 120 (10)
(Size 7-24)
SD Bushing
108 (9)
108 (9)
(Size 27-33)
252 (21) 288 (24)
Motor Mount
564 (47) 636 (53)
Motor Mount
Operation
IMPORTANT: The fan has been checked for
mechanical noise at the factory prior to
shipment. If mechanical noise should develop,
suggested corrective actions are offered in the
Troubleshooting section (page 10).
1. After the fan is installed, disconnect and lock-out all
power switches to fan.
2. Before connecting the fan to power, turn the fan
wheel by hand to be sure it is not striking the inlet
cone (venturi) or any obstacle.
3. Start the fan and shut it off immediately to check
rotation of the wheel, see Figure 2.
Wheel Rotation - Direction of wheel rotation is
critical. Reversed rotation will result in poor air
performance, motor overloading and possible
burnout. Rotation should be counterclockwise when
viewed from the fan inlet as shown in Figure 2. If
wheel rotation is incorrect, switch two of the wiring
leads for 3 phase power supply or check motor
wiring for single phase power supply. Fan rpm
should be checked and verified with a tachometer.
Figure 2
4. When the fan is started, observe the operation and
check for any unusual noises.
5. With the system in full operation and all ductwork
attached, measure current input to the motor and
compare with the nameplate rating to determine if
the motor is operating under safe load conditions.
6. Keep inlets and approaches to fan clean and free
from obstruction.
Inspection
Inspection of the fan should be conducted at the first 30
minute and 24 hour intervals of satisfactory operation.
30 Minute Interval - Inspect bolts, setscrews and motor
mounting bolts. Adjust and tighten as necessary.
24 Hour Interval - Check all internal components.
®
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