Model IGX Make-Up Air
26
®
Mixed Flow Plenum Fans
Mixed flow plenum fans are single width, single inlet
fans. The impellers are unhoused
with blades that curve away from
the direction of rotation. These
fans throw the air radially outward,
approximately 45°F from the inlet
direction, pressurizing the fan
cabinet. These fans are direct driven
with the impeller mounted directly to
the motor shaft. A “P” and “MF” are
present in the model number.
The fan type must be identified before performing the
supply fan pre-start checks and start-up. The unit was
supplied with one of three fan options.
Forward-Curved Fans
The forward-curved fans utilized in these units are
double width, double inlet, belt driven, housed
centrifugal fans. The
impeller is constructed
with shallow blades that
“scoop” the air. In some
instances, Models VSU
or TSU units use two
forward-curved fans with
a common shaft.
Backward-Curved Plenum Fans
Backward-curved plenum fans are single width, single
inlet fans. The impellers are
unhoused, with blades that
curve away from the direction of
rotation. These fans throw the air
radially outward, 90°F from the
inlet direction, pressurizing the
fan cabinet. These fans are direct
driven with the impeller mounted
directly to the motor shaft. A “P”
is present in the model number.
Backward-Curved
Plenum
Mixed Flow
Plenum
Forward-Curved
Supply Fan
Fan Identification
Model Number Code
A
(50 mbh)
B
(75 mbh)
C
(100 mbh)
D
(125 mbh)
E
(150 mbh)
F
(175 mbh)
G
(200 mbh)
H
(225 mbh)
I
(250 mbh)
J
(300 mbh)
K
(325 mbh)
L
(350 mbh)
M
(400 mbh)
N
(500 mbh)
O
(600 mbh)
P
(700 mbh)
Q
(800 mbh)
R
(1,000 mbh)
S
(1,050 mbh)
T
(1,200 mbh)
IGX - P1 20 - H22 - MF - C
Blower Quantity
1
Model Parent
IGX
Housing Size
12-32
Furnace Input
See List Below
Wheel Diameter (in.)
8 - 20
Optional Fan
*P - Plenum Supply Fan
*If no P is shown, then a forward-curved fan is provided.
Mixed Flow
