Desa (V)3612ST Installation And Operating Instructions Manual page 9

VENTING INSTALLTION
Continued
Living Space Above Ceiling
Figure 17 - Firestop Spacer For Living Space
Screw (8)
Attic Space
Above Ceiling
Figure 18 - Firestop Spacer for Attic Space
ELBOW OFFSET INSTALLATION
Chimney weight above offset rests on return elbow. Straps must be
secured with nails to rafters or joists (see Figure 19).
Strap
30 FT.
(9.14m)
Figure 19 - Elbow Offset
115603-01A
Existing Ceiling
Frame
Firestop Spacer
Screw (8)
Firestop Spacer
Existing Ceiling
Frame
12S-12DM
Support
Required
Return
Elbow
For more information, visit www.desatech.com
For more information, visit www.desatech.com
SUPPORT SECTIONS
The chimney support section is a 4-inch strap and 12 inch length of pipe.
A chimney support is required every 30 feet above the fireplace after a
straight chimney run, or above a return elbow after a straight chimney
run (see Figure 20). This support is designed to relieve the extra weight
load on the fireplace and elbows when high chimneys are installed.
To achieve desired offset, you may install combinations of 12, 18,
36, and 48 inch lengths of double wall pipe. See Figure 21 and Rise
and Offset Chart below.
2" (5.1cm)
Minimum
Straps
Return
Elbow
Figure 20 - Chimney Supports
RISE AND OFFSET CHART
A
(Offset) (Rise)
4 3 /
8
9 1 /
2
1
12 /
2
3
14 /
8
5
17 /
8
21 1 /
2
30 FT.
22 3 /
4
(9.14m)
26 3 /
8
26 3 /
8
3
31 /
4
3
34 /
4
5
38 /
8
39 7 /
8
43 3 /
4
3
46 /
4
7
48 /
8
FIRESTOP SPACERS
ELBOW OFFSET INSTALLATION
SUPPORT SECTIONS
Angled Firestop
Ceiling Support
Figure 21 - Rise and Offset
B Length of Pipe
48 36 18
16 3 / Elbow Set Only
8
25 1 / 1
4
3
30 / 1
8
34
1
39 / 1
4
46 1
48 1 / 1
8
54 7 / 1
8
60 1 1
3
63 / 1 1
4
69 1 1
5
75 / 2
8
77 7 / 1 1
8
84 1 / 1 1
2
3
87 / 2 1
4
3
93 / 2
8
9 9
B
A
12
2
1
2
1