4
Model H-G/H-GB Centrifugal Roof Exhaust Fan
Model H-GPF
or SD Curb
5/16 in. recommended
1/4 in. fastener minimum
See table for fastener quantities
Tie Down Detail (H-GB Only)
Fig. 7
Pre-Starting Checks
1. Check all fasteners and set screws for tightness. The
wheel should rotate freely and be aligned as shown
in figure 9.
2. Wheel position is preset and the unit is test run at the
factory. Movement may occur during shipment and
realignment may be necessary.
3. Only H-G unit - Centering height alignment can be
accomplished by loosening the set screws in the
wheel and moving the wheel to the desired position.
4. Only H-GB unit - Centering can be accomplished by
loosening the bolts holding the drive frame to the
shock mounts and repositioning the drive frame.
5. Only H-GB unit - Wheel and inlet cone overlap can
be adjusted by loosening the set screws in the wheel
and moving the wheel to the desired position.
6. Only H-GB unit - Fan RPM should be checked and
verified with a tachometer.
7. Check wheel rotation (viewing from the shaft side)
by momentarily energizing the unit. On a H-G unit
the rotation should correspond to the rotation decal
on the unit, see figure 10. On a H-GB unit rotation
should be clockwise as shown in Fig. 10 and
correspond to rotation decal on the unit. If wheel
rotation is incorrect reverse two of the wiring leads or
check motor wiring for single phase.
Table 1
Model
Fasteners Per Side
Total Fasteners
H-G 060 - 141
3
12
H-G 150 - 180
5
20
H-GB 071 - 161
3
12
H-GB 180 - 300
5
20
5. Secure fan to curb. Fasteners on each side of the fan
are to be installed with one fastener 4 in.
(102 mm)
from each edge and one fastener centered, see
figure 6 and table 1. Remaining fasteners should be
equally spaced in between. Shims may be required
depending upon curb installation and roofing
material.
6. Tie downs shall be run from one corner fastener thru
tie down point and attach with other corner fastener.
Tie downs are not required to meet 150 mph wind
loads for sizes 240 and smaller. (Tie downs are
included for sizes 260, 300 and 300HP.)
7. Verify power line wiring is de-energized before
connecting fan motor to power source.
8. Connect power supply wiring to the motor as
indicated on the motor nameplate or terminal box
cover. Check the power source for compatiblity with
the requirements of your equipment.
9. Check fan wheel for free rotation, re-center if
necessary.
10. Check all fasteners for tightness.
11. Mount and wire safety disconnect switch under
motor cover. Wire control switches at ground level,
refer to figure 8.
12. Replace motor cover.
MOTOR
L1
115/208-230/60/1
208-230/460/60/3
MOTOR
J-BOX
J-BOX
SUPPLY VOLTAGE
SUPPLY VOLTAGE
L2
L1
L2
L3
Typical Wiring Diagram
Fig. 8
Fan to Curb Mounting
Fig. 6
1/4 in. fastener minimum
5/16 in. recommended
FAN TO CURB MOUNTING DETAIL
H-GPF or SDCurb
Model H-G or H-GB
Fastener 4 in.
from curb edge
