Comfortflame.US.com
900574-00N/C
8
VENTING INSTALLATION
Continued
ASSEMBLY AND INSTALLATION OF DOUBLE WALL CHIMNEY
SYSTEM
SS-8DM starter section must be installed first.
Each double wall chimney section consists of a galvanized outer
pipe, a stainless steel inner flue pipe and a wire spacer. Pipe sections
must be assembled independently as chimney is installed. When
connecting chimney directly to fireplace, inner flue pipe section
must be installed first with lanced side up. Outer pipe section can
then be installed over flue pipe section with hemmed end up. Press
down on each pipe section until lances securely engage hem on
fireplace starter. Wire will assure proper spacing between inner
and outer pipe sections.
Note:
For Canada, use chimney parts designated HT.
Opening in collar around chimney at top of
fireplace must not be obstructed. Never use blown
insulation to fill chimney enclosure.
Continue to assemble chimney sections as outlined, making sure
that both inner and outer pipe sections are locked together. When
installing double wall snap-lock chimney together, it is important to
assure joint between chimney sections is locked. Check by pulling
chimney upward after locking. Chimney will not come apart if properly
locked. It is not necessary to add screws to keep chimney together
(exception - see Figure 7).
The height of a vertical chimney pipe supported
ONLY
by the
fireplace, must not exceed 20 feet. Chimney heights above 20 feet
must be supported.
USING ELBOW OFFSET 30E-12DMO-8DMR
To clear overhead obstructions, you may offset your chimney system
using
30E-12DMO-8DMR 30° Offset/return elbow.
A section or sections of chimney may be used between offsets and
return elbow. Transition pipe must be used after elbow offset is
attached.
1. To achieve desired offset, you may install combinations of 12",
18", 24", 36" and 48" length of double wall pipe (see offset chart).
Note:
For systems with 2 elbow sets, minimum height is 22 feet.
Maximum height for any system is 50 feet.
2. Chimney weight above offset rests on return elbow. Straps must
be securely nailed to rafters or joists (see Figure 9 details A and
B, page 9).
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 8, page 9).
4. All pipe connections between offset and return must be secured
with two screws on outer pipe only (see Figure 7). Do not pen
-
etrate inner stainless.
Figure 7 - Elbow Offset
OFFSET CHART WITH TRANSITION PIPE
OFFSET
RISE
OFFSET/
RETURN
ELBOW
TRANSITION
PIPE
CHIMNEY LENGTH
A
B
12"
18"
36"
48"
13
3
/
4
"
32
1
/
2
"
1
1
19"
41"
1
1
1
1
22"
46
3
/
4
"
1
1
1
24
1
/
2
"
50
3
/
4
"
1
1
2
27
1
/
2
"
56
1
1
1
1
30
1
/
4
"
61
1
1
2
31
62
1
/
2
"
1
1
1
32
1
/
2
"
65"
1
1
2
1
35
1
/
2
"
70
1
/
4
"
1
1
1
2
36
1
/
4
"
71
1
/
2
"
1
1
1
1
37
72
3
/
4
"
1
1
1
38
1
/
2
"
75
1
/
2
"
1
1
3
39
1
/
4
"
76
3
/
4
"
1
1
1
1
41
1
/
2
"
80
1
/
2
"
1
1
2
1
42
1
/
4
"
81
3
/
4
"
1
1
1
1
44
1
/
2
"
85
3
/
4
"
1
1
1
1
1
45
1
/
4
"
87"
1
1
1
1
47
1
/
2
"
91"
1
1
2
1
48
1
/
4
"
92
1
/
4
"
1
1
2
49
3
/
4
"
94
3
/
4
"
1
1
2
1
1
52"
98
3
/
4
"
1
1
1
4
53
1
/
2
"
101
1
/
4
"
1
1
1
2
54
1
/
4
"
102
3
/
4
"
1
1
1
1
55
3
/
4
"
105
1
/
4
"
1
1
3
1
56
1
/
2
"
106
1
/
2
"
1
1
1
2
58
3
/
4
"
110
1
/
2
"
1
1
2
2
59
1
/
2
"
111
3
/
4
"
1
1
1
1
1
60
1
/
4
"
113"
1
1
2
61
3
/
4
"
115
3
/
4
"
1
1
1
1
2
64
3
/
4
"
120
3
/
4
"
1
1
2
2
65
1
/
2
"
122
1
/
4
"
1
1
1
2
67"
124
3
/
4
"
1
1
2
1
2
B
A
Screws
