8
STEP 2: CUTTING RETURN AIR OPENING
For all wall return applications, cut the return air opening
to accomodate the return air box according to the same
dimensions. Remember, location of opening must allow
for a 90° bend in the return air duct.
Check the opening for proper fit of the return air box. Do
not install the return air box until the installation of the
entire Space-Pak system is completed, if you want to fit
materials up through this hole.
FIGURE 2.7: RETURN AIR BOX FRAME DIMENSIONS
AA
14 Ft. MAXIMUM FLEXIBLE
RETURN DUCT
AAAAAAA
FAN COIL UNIT
AAAA
AAAA
AAAAA
A
A
A
A
A
A
SUPPORT
SUPPORT
RETURN AIR BOX
90°
90°
2 Ft.
MAX.
PLATFORM (FIELD ERECTED
AS SHOWN IN STEP 4)
AAAAAA
SUPPLY
AIR
A
A
A
A
A
A
A
A
A
A
A
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FIGURE 2.6: VERTICAL AIR FLOW UNIT INSTALLATION
Select exact location for return air box. Avoid installing
box in dining room, living room, kitchen, etc., unless
return air duct can be installed with 180° bend
(accomplished by splicing two return air ducts together.)
For attic installations to raise fan coil unit up through
opening, cut return air opening 14
1
/
2
" wide by 27" long for
the ESP-2430D and the ESP-3642D and 14
1
/
2
" wide by
37” long for the ESP-4860D. These openings will
accomodate the return air box with sufficient frame lip to
cover the opening (see Figure 2.7).
If joists are on 16" centers, the 14
1
/
2
" width of the return
air box should fit between successive joists. Where joists
run in the opposite direction, or to properly center the
return, it may be necessary to cut joists and install
headers.
HINGED
PANEL
LOUVERS
1/2"
A
B
4"
16-1/2"
14-5/16"
AAAAAAAAA
AAAAAAAAA
AAAAAAAAA
AAAAAAAAA
AAAAAAAAA
MODEL
A
B
SPC-1D
SPC-2D
25"
36-3/8"
28"
38-9/16"
SPC-3D
36-3/8"
38-9/16"
