Vermont Castings 33CFDVNV Installation And Operating Instructions Manual page 29

VENTING INSTALLATION
NOTE: Flex vent pipe spacers: Refer to manufacturer's
specifications for correct positioning of the
spacer springs to maintain proper distance
between inside and outside pipe.
Install the Ceiling Firestop
• Frame an opening 9 in. x 9 in. (229 mm x 229 mm)
whenever the vent system penetrates a ceiling/floor .
Figure 55
• Frame the area with the same sized lumber as used in
ceiling/floor joist.
• When installing a top vent vertical termination appliance
the hole should be directly above the appliance, unless
the flue is offset.
• The ceiling firestop may be installed above or below
the ceiling. Figure 56
• Secure with three fasteners on each side.
• Do not pack insulation around the pipe. Insulation must
be kept away from the pipe.
• The gap between the vent pipe and firestop may be
sealed.
UL1777
Flex Vent
Figure 54 –
Minimum Radius for Flex Vent Section
FP1973
flex pipe bend
20306739
5" Radius
Figure 55 –
Installing Ceiling Firestop
Install attic insula-
tion shields before
or after installation
of vent system.
3 fasteners
Ceiling firestop
installed below ceiling.
Figure 56 –
Installing Ceiling Firestop & Attic Insulation Shield
CFDV Series Gas Fireplace
Attic Above
9 in. (229 mm)
9 in. (229 mm)
Hole should measure
9 in. x 9 in.
inside to inside
per side
Ceiling firestop
installed above ceiling.
29