Using Offsets/Returns - Heat & Glo Montana-36 Owner's Manual

B. Using Offsets/Returns
To bypass any overhead obstructions, the chimney may be
offset using an offset/return.
An offset and return may be attached together or a chimney
section(s) may be used between an offset and return.
Perform the following steps to determine the correct chim-
ney component combination for your particular installation:
WARNING
Fire Risk
• Draft will be restricted if offsets/returns
greater than 30° are used.
Table 5.2
A B
in. mm in.
4 7/8 124 17 7/8
7 1/4 184 2 2
9 3/4 248 26 1/8
10 1/4 260 27 1/4
12 3/4 324 31 3/8
13 1/4 337 32 3/8
15 3/4 400 36 5/8
18 1/8 460 40 3/4 1035
18 3/4 476 41 3/4 1060
21 3/4 552 47 1194
22 1/4 565 48 1219
24 3/4 629 52 1/8 1324
27 3/4 705 57 3/8 1457
28 1/4 718 58 3/8 1483
30 3/4 781 62 1/2 1588
33 3/4 857 67 3/4 1721
36 3/4 933 73 1854
39 3/4 1010 78 1/8 1984
41 1/8 1045 82 3/8 2092
45 3/4 1162 88 1/2 2248
48 1/8 1222 92 3/4 2356
51 3/4 1314 98 7/8 2511
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.
16 Heat & Glo LifeStyles Collection • Montana US-CAN • 4039-156 Rev C • 11/07
SL1106 SL1112 SL1118
mm SL406 SL412 SL418
454 - - -
559 1 - -
664 2 - -
692 - 1 -
797 1 1 -
822 - - 1
930 - 2 -
1 2 -
- 1 1
- - 2
- - -
1 - -
- 1 -
- - -
1 - -
- 1 -
- - 1
- - -
1 - -
- - -
1 - -
- - -
• Measure how far the chimney needs to be shifted to enable
it to avoid the overhead obstacle. See Figure 5.1. Use
dimension "A" to determine chimney section required to
achieve the needed shift.
• After determining the offset dimension, refer to Table 5.2
and fi nd the "A" dimension closest to but not less than the
distance of shift needed for your installation.
• The "B" dimension that coincides with the "A" dimension
represents the required vertical clearance that is needed
to complete the offset and return.
• Read across the chart and fi nd the number of chimney
sections required and the model number of those particular
chimney parts.
• Whenever the chimney penetrates a fl oor/ceiling, a ceiling
fi restop must be installed.
• The effective height of the fi replace assembly is measured
from the base of the fi replace to the top of the starter collar.
See Dimensions in Section 12.
SL1136 SL1148
SL436 SL448
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
Figure 5.1
1 -
1 -
Example: Your "A" dimension from Figure 5.3 is
1 -
14 1/2 in. (368 mm). Using Table 5.2 the dimension
closest to, but not less than 14 1/2 in. (368 mm) is
- 1
15 3/4 in. (400 mm) using a 30° offset/return. It is
- 1
then determined from the table that you would need
- 1
36 5/8 in. (930 mm) (Dimension "B") between the
- 1
offset and return. The chimney components that best
2 -
fi t your application are two SL1112s or SL412s.
2 -
1 1
1 1
- 2
A
B
1-1/4 in. (32 mm)
OVERLAP
Chimney Offset/Return