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116010-01E
7
VenTing insTallaTion
Continued
Continue to assemble chimney sections as
outlined above, making sure that both inner
and outer pipe sections are locked together.
When installing double wall snap-lock chim
-
ney together, it is important to assure the joint
between chimney sections is locked. Check
by pulling chimney upward after locking. The
chimney will not come apart if properly locked. It
is not necessary to add screws to keep chimney
together (exception, see Figure 7).
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
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
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).
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 sup
-
ports (return elbow or 12S-12DM) is 6'
of angle run. Maximum of two 6' angle
run sections per chimney system (see
Figure 9, page 8).
4. All pipe connections between offset and
return must be secured with two screws
on outer pipe only (see Figure 7). Do not
penetrate 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
Figure 7 - Elbow Offset
B
A
Screws
