Rheem RRNL Installation Instructions Manual page 18

FIGURE 13
FIGURE 10
EXCEPTION TO NON-COMBUSTIBLE FLOORING REQUIREMENT
EXCEPTION TO NON-COMBUSTIBLE FLOORING REQUIREMENT
18
SIDEFLOW
SUPPLY
PLENUM
CONNECTION
NOMINAL
4 x 4 TIMBER
(SIDES ONLY)
1" MIN.
SUPPLY
PLENUM
(DOWNFLOW)
FIGURE 14
FLAT ROOFTOP INSTALLATION, ATTIC OR DROP CEILING DISTRIBUTING SYSTEM. MOUNTED ON
ROOFCURB, PITCH UNIT TOWARD DRAIN.
BOTH ENDS
MUST BE
SIDEFLOW
OPEN FOR
RETURN PLENUM
DOWNFLOW
CONNECTION
OR SIDEFLOW
DUCTWORK
TO PROVIDE
VENTILATION
3-1/2" MIN.
COMBUSTIBLE
STRUCTURE
RETURN PLENUM
(DOWNFLOW)
FIGURE 15
PITCHED ROOFTOP INSTALLATION, ON ANGLE-IRON STAND, SIDE FLOW DUCTWORK,
ATTIC OR DROP CEILING
DISTRIBUTING SYSTEM.
PITCH UNIT TOWARD DRAIN.
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