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125898-01D
17
VENTING INSTALLATION
Continued
2. Assemble desired lengths of pipe and
and elbow connections are fully twist-
3. Cut a hole in the roof using locating hole
as a center point. (Cover any exposed
open vent pipes before cutting hole in
1
/
2
" x 11
1
/
2
" hole must be
may be larger depending on pitch of roof.
There must be a 1" clearance from vent
pipe to combustible materials. Frame
opening as shown in Figure 9 page 12.
4. Connect a section of pipe and extend up
through hole.
Note: If an offset is needed to avoid
obstructions, you must support vent pipe
every 3 feet. Use wall straps for this pur-
pose (see Figure 14, page 15). Whenever
possible, use 45° elbows instead of 90°
elbows. The 45° elbow offers less restric-
-
tending through roof. Secure base of
16. There must be a 1" clearance from
vent pipe to combustible materials.
6. Continue to add pipe sections until height
of vent cap meets the minimum building
code requirements described in Figure 7
on page 10.
Note: You must increase vent height for
steep roof pitches. Nearby trees, adjoining
similar factors may cause poor draft or
down-drafting in high winds. Increasing
vent height may solve this problem.
7. Twist-lock vent cap onto last section of
vent pipe.
Note: If vent pipe passes through any occupied
and closets, you must enclose pipe. You may
frame and sheetrock enclosure with standard
construction material. Make sure and meet the
minimum allowable clearances to combustibles.
Figure 17 and 18, page 17 and 18, shows the
Figure 18 - Vertical Venting
Note:
Vertical (V
1
2
V + H = 40' Max.
H=20' Max.
Horizontal
5' Min.
10' Max
6' Min.
14' Max
7' Min.
20' Max
20' Max.
20' Max
Note: Install a
VR-58 vertical
restrictor ring
into inner pipe
section prior to
attaching vent
termination cap.
90°
Elbow
