8
STEP 2: CUTTING RETURN AIR OPENING
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 at least two 90°
bends (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 the "A"
dimension (Figure 2.6) of appropriate unit size. These
openings will accomodate the return air box with suffi-
cient frame lip to cover the opening (see Figure 2.6).
NOTICE: The return air adapter may need to be removed
from the unit to fit through the opening cut out.
Refer to the "Installation Tip" supplied with the return
air box.
If ceiling 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.
For all wall return applications, cut the return air opening
to accomodate the return air box (measure box itself).
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 SpacePak system is completed, if you want to fit
materials up through this hole.
14 Ft. MAXIMUM FLEXIBLE
RETURN DUCT
FAN COIL UNIT
SUPPORT
RETURN AIR BOX
90°
90°
2 Ft.
MAX.
PLATFORM (FIELD ERECTED
AS SHOWN IN STEP 4)
SUPPORT
FIGURE 2.5: HORIZONTAL AIR FLOW UNIT INSTALLATION
CLAMP BAND
CLAMP BAND
RETURN AIR BOX
WITH GRILL & FILTER
SPACEPAK FAN
COIL UNIT
FLEXIBLE RETURN
DUCT (90 BEND)
48" MIN.
PLATFORM (FIELD ERECTED
AS SHOWN IN STEP 4)
SUPPLY AIR OUTLET
FIGURE 2.4: TYPICAL UNIT INSTALLATION
