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5292157-UIM-B-0317
Johnson Controls Unitary Products
7
Use flexible duct collars to minimize the transmission of vibration/noise
into the conditioned space. If electric heat is used, non-flammable
material must be used.
All ducts should be suspended using flexible hangers and never
fastened directly to the structure.
HORIZONTAL SUSPENSION
These air handlers may be suspended in horizontal applications. It is
recommended to use angle steel support brackets with minimum 3/8”
threaded rods, supporting the unit from the bottom. Attach the threaded
rods at the locations shown in the Figure 7, leaving enough clearance
between door and rod so that doors maybe easily removed for service.
DUCT FLANGES
Three duct flanges are provided to assist in positioning and attaching
duct work to the air handler. These flanges are included in the unit parts
bag. With the screws from the parts bag, install one of the duct flanges.
Duct flanges have holes on both legs with one leg longer than the other.
The longer leg can be used to mate against the air handler so that
different thicknesses of duct board can be made flush with the outer
surface of the air handler. Repeat the procedure for the other two
flanges. Refer to Figure 8. If the flanges are not used, they may be
discarded.
UNIT CONNECTIONS
There are several ways to handle the supply and return air duct
connections. The location and sizing of the connections depends on the
situation and the method best suited to the installation. Upflow,
horizontal or downflow applications may be used.
The supply air duct should be properly sized by use of a transition to
match unit opening. Refer to Table 1 for air handler unit inlet and outlet
dimensions.
Duct work that is not designed to match the supply air opening can
cause turbulence inside the plenum. This turbulence can change the air
flow patterns across the electric heater limit switches. If the factory
suggested transition cannot be fabricated, it is recommended that a
block off plate (approximately 8" high and running the full width of the
plenum) be attached to the supply opening. Refer to Figure 9 as a
visual aid. The use of this block off plate will enable better air circulation
across the limit switches.
CAUTION
This unit is not designed for non-ducted (freeblow) applications. Do
not operate without duct work attached to unit.
Equipment should never be operated without filters.
CAUTION
DO NOT lift air handler by the cabinet brace. The cabinet brace is
held in place by the coil channel. The cabinet brace could become
disengaged from the cabinet causing the air handler to fall, potentially
causing injury or damaging property. See Figures 2 or 3 for location of
cabinet braces.
NOTICE
When assembling the support structure, make sure to size to provide
clearance for access door removal.
Dimension in Inches
Air Handler Cabinet Size
X
H
17-1/2 Width-Short H
21
41
17-1/2 Width-Long H
21
47-1/2
21 Width-Short H
21-1/2
51-1/2
21 Width-Long H
21-1/2
55-3/4
24-1/2 Width
21-1/2
55-1/2
FIGURE 7:
Horizontal Suspension
!
!
S
U
S
PEN
S
I
O
N
S
UPP
O
RT L
OC
ATI
O
N
S
F
O
R H
O
RIZ
O
NTAL APPLI
C
ATI
O
N
S
X
H
2”
1
-
1
/2”
M
IN.
1
-
1
/2” x
1
-
1
/2”
A
ng
l
e
R
e
co
mmended
l
engt
h 26”
minimum
w
it
h 2” cl
earan
c
e
o
n
bo
t
h
sides
o
f
A
ir
H
and
l
er
M
IN. 3/8”
THREADED R
O
D
X
H
1
-
1
/2”
1
-
1
/2”
M
IN.
1
-
1
/2” x
1
-
1
/2”
A
ng
l
e
R
e
co
mmended
l
engt
h 26”
minimum
w
it
h 2” cl
earan
c
e
o
n
bo
t
h
sides
o
f
A
ir
H
and
l
er
M
IN. 3/8”
THREADED R
O
D
A
0
33
1
-
001
FIGURE 8:
Duct Attachment
FIGURE 9:
Duct Work Transition
CAUTION
Use 1/2” screws to connect duct work to unit. Longer screws will
pierce the drain pan and cause leakage. If pilot holes are drilled, drill
only though field duct and unit bottom duct flange.
A
0
445-
001
DU
C
T FLANGE
S
(
S
h
i
pp
ed
in
b
ag
w
it
h
unit
)
A
0
332-
001
RE
COMM
ENDED
TRAN
S
ITI
O
N
S
UGGE
S
TED L
OC
ATI
O
N
O
F BL
OC
K
O
FF PLATE
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