Advent Roof Top Installation And Operating Instructions Manual page 6

C. OPENING PREPARATION:
1. If the opening exceeds 14-3/8" x 14-3/8", it will be necessary to install spacers.
2. If the opening is less than 14-1/8" x 14-1/8", it must be enlarged.
3. Route a 12/3 Romex type supply line from the fuse or circuit breaker box to the front of
roof opening.
a. The power supply must be on a separate 20 amp Time Delay Fuse or HACR
Circuit Breaker.
b. Wiring must comply with all National, State and Local wiring codes.
c. Make sure at least 15" of wire extend into the roof opening to ensure easy
connections.
4. The opening must be framed to provide adequate support and prevent air from being
drawn from the roof cavity. Lumber 3/4" thick or more and long enough to bridge the
opening must be used. Remember to provide an entrance hole in the front of the opening
for 110v, 12v, and thermostat wires. See FIG. 5.
5. The 14-1/4" x 14-1/4"(±1/8) roof opening is part of the return air duct and must be finished
in accordance with NFPA standard 501C, Standard for Recreational Vehicles, Section 2-7.
It is the responsibility of the installer of this air conditioner system to ensure
structural integrity 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 product and RV
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