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109493-01R
8
VenTing insTallaTion
Continued
USING ELBOW OFFSETS (30E-12DM)
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 7).
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
Figure 7 - Typical Offset Terminations
Return
Elbow
Offset
Elbow
Return
Elbow
Offset
Elbow
6' Max.
6' Max.
6' Max.
6' Max.
6' Max.
6' Max.
Return
Elbow
Offset
Elbow
Offset
Elbow
Return
Elbow
A
B
C
Offset
Elbow
Ceiling
Support Pipe
12S-12DM
Return
Elbow
Figure 8 - Ceiling Support Pipe
12S-12DM
2" Min.
Straps
Straps
Straps
Straps
Detail A
Return Elbow
Detail B
Angle Firestop
See Detail A
See Detail B
2. Chimney weight above offset rests on
return elbow. Straps must be securely
nailed to rafters or joists (see Figure 8,
details a and b).
3. Maximum length of pipe between supports
(return elbow or 12S-12DM) is 6' of angle
run. Maximum of two 6' angle run sections
per chimney system (see Figure 7).
4. All pipe connections between the offset
and return must be secured with two
screws on the outer pipe only (see Figure
9, page 9). Do not penetrate the inner
stainless.
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
