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125192-01B
10
VENTING INSTALLATION
Continued
OFFSET
RISE
CHIMNEY LENGTH
A
B
12" 18" 24" 36" 48"
4
3
/
8
"
16
3
/
8
"
ELBOW SET ONLY
9
3
/
4
"
25
1
/
2
"
1
12
3
/
4
"
30
3
/
4
"
1
15"
34
3
/
4
"
1
18"
40"
1
1
21
1
/
4
"
46
1
/
4
"
1
23
3
/
4
"
49
1
/
4
"
1
1
27
3
/
4
"
56
3
/
4
"
1
30"
60
3
/
4
"
1
1
33"
66"
1
1
36"
71"
1
1
38
1
/
4
"
75"
2
41
1
/
4
"
80
1
/
4
"
1
1
1
45"
86
3
/
4
"
2
46
3
/
4
"
89
1
/
2
"
1
1
1
51"
97"
1
1
53
1
/
4
"
101"
1
2
56
1
/
4
"
106
1
/
4
"
2
59
1
/
4
"
111
1
/
2
"
1
1
1
61
3
/
4
"
115
1
/
2
"
1
2
64
3
/
4
"
120
3
/
4
"
1
2
68
1
/
4
"
127"
2
1
70"
130"
1
1
2
74
1
/
4
"
137
1
/
2
"
1
2
1
76
3
/
4
"
141
1
/
2
"
1
2
1
79
3
/
4
"
146
3
/
4
"
4
USING ELBOW OFFSETS (30E-8DM)
1.
To achieve desired offset, you may install
combinations of 12", 18", 24", 36" and 48"
length of double wall pipe (see offset chart
and Figure 12).
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
Figure 13 - Ceiling Support Pipe
12S-8DM
Straps
Straps
Straps
Straps
Detail A
Return Elbow
Detail B
Angle Firestop
See
Detail A
See Detail B
Figure 12 - Elbow Offset
B
A
Screws
2. Chimney weight above offset rests on
return elbow. Straps must be securely
nailed to rafters or joists (see Figure 13,
details A and B).
3. Maximum length of pipe between supports
(return elbow or 12S-8DM) is 6' of angle
run. Maximum of two 6' angle run sections
per chimney system (see Figure 12).
4. All pipe connections between offset and
return must be secured with two screws
on outer pipe only (see Figure 14). Do not
penetrate inner stainless.
