Specifications

4
location of any inner roof plumbing and electrical supplies
must be considered.
A. If a roof vent is already present in the desired
mounting location for the air conditioner, the
following steps must be taken:
1. Remove all screws which secure the roof
vent to the vehicle. Remove the vent and
any additional trim materials. Carefully
remove all caulking from around the roof
vent opening to obtain clean exterior roof
surface.
2. It may be necessary to seal some of the old
roof vent mounting screw holes which may
fall outside of the air conditioner basepan
gasket.
3. Examine the roof opening. If the opening is
smaller than 14” x 14”, the opening must be
enlarged. If the opening exceeds 15” x 15”,
a mounting frame must be field fabricated
to reduce the opening size (See Figure 1).
B. If a roof vent opening is not used, a new opening
(See Figure 1) will have to be cut into the vehicle
roof. A matching opening will also have to be cut
into the interior vehicle ceiling. Be careful when
cutting the ceiling opening. If the ceiling opening
is carpeted, snagging could occur. After the opening
in the roof and interior ceiling are the correct size, a
framed support structure must be provided between
exterior roof top and interior ceiling. The reinforced
framed structure must provide the following
guidelines:
After the support frame is installed, seal off all gaps
between the frame and both the roof exterior and the
interior ceiling of the vehicle (cavity walls).
Additionally, seal the gap around the electrical
supply wiring.
C. This air conditioner is to be installed in accordance
with NFPA Standard 501C.
D. The roof top air conditioner must be mounted as
near level from front to rear and side to side as is
possible when the vehicle is parked on a level plane.
Figures 2 and 3 show maximum allowable degree
deviations (mounting degrees from total surface flat
plane).
1. Capable of supporting both the weight of
the roof top air conditioner and the interior
ceiling assembly.
2. Capable of holding or supporting the roof
outer surface and interior ceiling apart, so
that when the roof top air conditioner and
ceiling assembly are bolted together, no
collapsing occurs.
Airxcel’s 48000 series requires that the spacing from
the vehicle roof top to the interior ceiling be no less
than 1”. A typical support frame is shown in Figure
1.
The frame must provide an opening to allow passage
for the power supply wiring. Route the supply wiring
through the frame at the same time the support frame
is being installed.
IMPORTANT – Allow 24” of supply wiring
through the support frame (working length).
Holes For
Wires
Typical Wood Frame
1"
Minimum
Thickness
FIGURE 1
2 ½"
Minimum
14"