Nortek P7RE Series, Installation Instructions Manual

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Figure 4. return air box
Return Duct
1. Assemble the collar by overlapping the two ends.
note: One end of the collar is slotted and the opposite
end has two small holes. Position the end with small
screw holes underneath the slotted end.
2. Fasten the collar ends with two self drilling sheet metal
screws.
3. Position the collar over the unit opening. Align the
four holes in the collar with the four dimples or holes
(depending on unit model) in the panel.
4. Secure the collar to the rear panel using self drilling
screws (10-16x.5).
locating & installing the return air assembly
To simplify installation, locate and install the return air
assembly first. If desired, the return opening can be
located inside a closet with louvered doors that has an
open area equal to or greater than a 12” x 20” grille. The
return air grille can be placed in the wall of a closet and
the air ducted into the filter box through a boxed-in area
at the closet floor level (
Figure 4 ).
Verify the filter is
readily accessible.
note:
The return air box with grille and filter should not
be located in heavy traffic areas like hallways or center
of rooms. A good spot is in a corner or under a table, if a
minimum two inch clearance is available.
1. Start the installation from under the home by cutting a
small hole in the subfloor. Determine how the floor joist
location will affect cutting the opening needed for the
return air box. note: Floor joists are generally located
on 16” centers, leaving 14-3/8” between joists.
2. After measuring the return air box (approximately 12-
1/4” x 20-1/4”), cut the hole through the floor so that
the box will fit between the floor joists. Care should be
taken when cutting through carpeting to avoid snags.
note:
In most installations it will be necessary to cut a
similar hole in the fiberboard directly under the hole in
the floor. However, if the floor is more than ten inches
deep, it will only be necessary to cut a hole for the collar
on the return air box or for the insulated duct.
3. Set the box into the opening and fasten with screws or
nails.
4. Install the filter and return air grille in the air box.
connecting the return & Supply air Flexible ducts
• Flexible ducts can be connected to the corresponding
fittings with the clamps provided with the ducts. See
Figure 9 & Table 4, (page 12) .
note:
To prevent a
loss in cooling capacity, make sure all connections are
tight.
• The flexible ducts may be cut to the required length,
see instructions packed with duct. Keep all ducts as
short and straight as possible. Avoid sharp bends.
• Ducts may be spliced with sheet metal sleeves and
clamps.
• After the inner duct is connected to the proper fitting,
the insulation and plastic sleeve should be pulled over
the connection and clamped.
• Homes with multiple supply ducts (or special
applications), a Y fitting is available to divide the
supply air so it can be ducted to different areas of the
home for more efficient cooling. note: For maximum
performance, insulate the Y fitting.
locating & installing the Supply damper(s)
caution:
if installing this air conditioning system in
conjunction with a furnace, a damper must be
installed in the furnace base assembly to prevent
cold air from being discharged around the heat
exchanger. damage to the heat exchanger and
asphyxiation may occur if a damper is not
installed.
check with the furnace manufacturer for damper
requirements. Failure to install the required
furnace damper may invalidate code agency
listing and limited warranty on the furnace.
When locating the supply damper(s), carefully check
floor joists and frame members that could interfere with
the installation of the damper or flexible duct. Ideally, the
damper should be located in the bottom of the main duct,
forward of center of the home, at least three feet from the
nearest register. See
Figure 5 (page 7) . The round
supply opening in the slanted side of the damper should
face the side of the home where the air conditioner is
located.
1. Locate the center of the heat duct by cutting a small hole
in the fiberboard below the duct at the desired location.
2. Cut a hole approximately 3/4” larger than the damper
opening in the fiberboard.
3. Cut a 9-1/8” x 13-1/8” hole in the duct and bend over
all tabs flat on the inside of the heat duct.
4. Insert the damper into the duct and bend over all tabs
flat on the inside of the heat duct.
5. Seal the opening between the fiberboard and damper
or flexible duct.