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INSTRUCTIONS WHEN ELBOW OFFSET (30E-8DM)
OF CHIMNEY IS NEEDED
1. To achieve desired offset, you may install combinations of
12”, 18”, 24”, 36” and 48” length of double wall pipe (SEE
SINGLE OFFSET CHARTAND FIGURE 6).
2. Chimney weight above offset rests on return elbow.
Straps must be securely nailed to rafters or joists (see figure 7,
details a & b).
3. Maximum length of pipe between supports (return elbow
or 12S-8DM) is 6’ of angle run. Maximum of two (2) 6’ angle
run sections per chimney system (see figure 6).
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
FIRESTOP SPACERS (FS-8DM)
Firestop spacers are required at each point where the chimney
penetrates a floor space. Their purpose is to establish and
maintain the required clearance between the chimney and the
combustible materials.
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 9.
They also provide complete separation from one floor space to
another 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 placed into an attic floor as shown
in figure 10.
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 7 CEILING SUPPORT PIPE
Figure 8 ELBOW OFFSET
All pipe connections between the offset and return
must be secured with two screws, only on the outer
pipe, and shall not penetrate the inner stainless.
Figure 9 FIRESTOP SPACER
Figure 10 FIRESTOP SPACER
WARNING
: The opening in the collar around the
chimney at the top of the fireplace must not be obstructed.
Never use blown insulation to fill the chimney enclosure.
