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INSTRUCTIONS WHEN OFFSET OF CHIMNEY IS
NEEDED
Installing offset and return elbow (30E-8DM)
1.
To achieve desired offset, you may install
combination of 12”, 18”, 24”, 36” and 48” length of
double wall pipe (see figures 13 and 14).
2.
The chimney weight above the offset rest on return
elbow. Straps must be securely fastened to rafters or
joists (see figure 15, details A & B).
3.
Maximum length of pipe between supports (return
elbow or chimney support V12S-8DM) is 6’ of
angled run. Maximum of two (2) 6’ angled run
sections per chimney system.
FIRESTOP SPACERS: (FS-8DM)
Firestop spacers are required at each point where the chimney
penetrates a floor or ceiling joist space. Their purpose is to
establish and maintain the required clearance between the
chimney and the combustible materials.
They also provide complete separation from one floor space to
another floor or attic space as required by most codes. When
the double wall pipe passes through a framed opening into an
attic space, the firestop must be place into the attic floor as in
figure 16.
When the pipe passes through a framed opening into a living
space above, the firestop must be placed onto the ceiling from
below as shown in figure 16.
1 elbow set – 16 to 60 ft. system height, 2 elbow sets – 30 to 60 ft. system height.
Figure 13 TYPICAL OFFSET INSTALLATIONS
Figure 14 OFFSET CHART
All pipe connections between
the offset and return must be
secured with two screws,
only on the outer pipe, and
must not penetrate the inner
stainless.
OFFSET
RISE
A
B
48"
36"
24"
18"
12"
4 - 3/8
16 -3/8
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
2
1
56 - 1/4
106 - 1/4
2
59 - 1/4
111 - 1/2
1
1
1
61 - 3/4
115 - 1/2
2
1
64 - 3/4
120 - 3/4
2
1
68 - 1/4
127
1
2
70
130
2
1
1
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
ELBOW SET ONLY
CHIMNEY LENGTH
Figure 15 OFFSET PIPE SUPPORT
