16
Heat & Glo • Rutherford 42-B Installation Manual • 4059-712 • Rev O • 09/28/15
Table 4.3 Offset Dimensions
B. Offsets/Returns
• Use an offset/return to bypass overhead obstructions.
• An offset and return can be used as a single entity or separated by chimney section(s).
WARNING!
Risk of Fire! DO NOT use offset/returns greater than 30°. Chimney draft will be restricted and could cause
overheating and fire. Secure offsets with screws ( not to exceed 1/2” / 13 mm in length) Secure returns with strapping.
Straight chimney sections may be secured with screws. Keep chimney sections from separating or twisting.
• Measure the shift needed to avoid the overhead obstruction. Refer to dimension A in Figure 4.2.
• Find the appropriate A dimension listed in Table 4.3. The B dimension coinciding with the A dimension measurement in
Table 4.3 represents the required vertical clearance needed to complete the offset/return.
• Read across the chart to find the number of chimney sections/model numbers needed between the offset and return.
A
B
1-1/4 in. (32 mm)
OVERLAP
Figure 4.2 Chimney Offset/Return
Example:
Your “A” dimension from Figure 4.2 is 14-1/2 in.
(368 mm). Using Table 4.3 the dimension closest to, but
not less than 14-1/2 in. (368 mm) is 15-3/4 in. (400 mm)
using a 30° offset/return.
You determine from the table that you need 36-5/8 in.
(930 mm) (Dimension “B”) between the offset and return.
The chimney components that best fits your application
are two SL1112’s.
A
B
SL1106 SL1112 SL1118 SL1136 SL1148
in.
mm
in.
mm
4 7/8
124
17 7/8
454
-
-
-
-
-
7 1/4
184
22
559
1
-
-
-
-
9 3/4
248
26 1/8
664
2
-
-
-
-
10 1/4
260
27 1/4
692
-
1
-
-
-
12 3/4
324
31 3/8
797
1
1
-
-
-
13 1/4
337
32 3/8
822
-
-
1
-
-
15 3/4
400
36 5/8
930
-
2
-
-
-
18 1/8
460
40 3/4
1035
1
2
-
-
-
18 3/4
476
41 3/4
1060
-
1
1
-
-
21 3/4
552
47
1194
-
-
2
-
-
22 1/4
565
48
1219
-
-
-
1
-
24 3/4
629
52 1/8
1324
1
-
-
1
-
27 3/4
705
57 3/8
1457
-
1
-
1
-
28 1/4
718
58 3/8
1483
-
-
-
-
1
30 3/4
781
62 1/2
1588
1
-
-
-
1
33 3/4
857
67 3/4
1721
-
1
-
-
1
36 3/4
933
73
1854
-
-
1
-
1
39 3/4
1010
78 1/8
1984
-
-
-
2
-
41 1/8
1045
82 3/8
2092
1
-
-
2
-
45 3/4
1162
88 1/2
2248
-
-
-
1
1
48 1/8
1222
92 3/4
2356
1
-
-
1
1
51 3/4
1314
98 7/8
2511
-
-
-
-
2
Proper assembly of air cooled chimney parts results in an overlap of chimney joints
of 1-1/4 in. (32 mm). Effective length is built into this table.