Roof Preparation - Dometic B3351.531 Installation & Operating Instructions Manual

FIG. 4
194mm
360
133
m m
m m
194mm
360mm x 360mm
Opening
Front
of
Unit
510mm
285
m m

ROOF PREPARATION

A. ROOF VENT REMOVAL:
1. Unscrew and remove the roof vent.
2. Remove all caulking compound around opening.
3. Seal all screw holes and seams where the roof
gasket will be located. Use a good grade of all
weather sealer.
B. NEW OPENING:
(Installations Other Than Vent Openings)
! WARNING
There may be electrical wiring between the
roof and the ceiling. Disconnect 220-240volt
AC power cord and the positive (+) 12 volt
DC terminal at the supply battery. Failure to
follow this instruction may create a shock
hazard causing death or severe personal in-
jury.
1. A 360mm x 360mm opening must be cut through the
roof and ceiling of the RV. It is recommended this
opening be located between roof reinforcing mem-
bers.
2. Mark a 360mm x 360mm square on the roof and
carefully cut the opening.
3. Using the roof opening as a guide, cut the matching
hole in the ceiling. See FIG. 4.
INSTALLATION AND OPERATING INSTRUCTIONS
Rear
of
378
m m
Unit
460
m m
75mm
75mm
285
m m
C. OPENING PREPARATION:
1. If the opening exceeds 365mm x 365mm, it will be
necessary to install spacers.
2. If the opening is less than 355mm x 355mm, it must
be enlarged.
3. The opening must be framed to provide adequate
support and prevent air from being drawn from the
roof cavity. Lumber 20mm thick or more and long
enough to bridge the opening must be used. Re-
member to provide an entrance hole for the power
supply wire. See FIG. 5.
20mm
Min.
FIG. 5
4. In addition to the frame, the opening must be
reinforced with (10 mm or more thick) strips of
plywood at least 90mm wide around all 4 sides of the
cut out hole. This will help provide strength to accept
the wood screws needed to secure the air box. The
strips must be glued in place onto the ceiling
material. See FIG. 6.
FIG. 6
90mm
It is the responsibility of the installer of this air
conditioner system to ensure structural in-
tegrity of the RV roof. Never create a low spot
on the roof where water will collect. Water
standing around the air conditioner may leak
into the interior causing damage to the prod-
uct and the RV.
5. Route a copper 1.5mm
from the fuse or circuit breaker box to the roof
opening.
a. The power supply must be on a appropriately
fused circuit.
5
Provide
Frame
Hole For
Opening
Wiring
90mm
360x 360mm
Cut Out
90mm
90mm
CAUTION
2
with ground, supply line