Warning, Table 21.1 c. using offsets/returns – Hearth and Home Technologies C-40 User Manual
Page 21
November 11, 2008
Heatilator • Constitution EPA Fireplace • 480-1091C
Page 21
• Measure how far the chimney needs to be shifted to enable
it to avoid the overhead obstacle. See Figure 21.2. Use
dimension “A” to determine chimney section required to
achieve the needed shift.
• After determining the offset dimension, refer to Table 21.1
and find 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 find the number of chimney
sections required and the model number of those particular
chimney parts.
• Whenever the chimney penetrates a floor/ceiling, a ceiling
firestop must be installed.
• The effective height of the fireplace assembly is measured
from the base of the fireplace.
Table 21.1
C. 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:
Fire Risk
DO NOT combine offsets to create an offset
greater than 30° from vertical.
• Draft will be restricted.
WARNING
A
B
1-1/4 in. (32 mm)
OVERLAP
Figure 21.2 Chimney Offset/
Return
Example:
Your “A” dimension from Figure 21.2 is
14 1/2 in. (368 mm). Using Table 21.1
the dimension closest to, but not less
than 14 1/2 in. (368 mm) is 14 1/2 in.
(368 mm) using a 30° offset/return. It is
then determined from the table that you
would need 34 1/8 in. (867 mm) (Dimen-
sion “B”) between the offset and return.
The chimney component that best fits
your application is one SL324.
Part SL315
Part SL315
SL306 SL312 SL318 SL324
SL336 SL348
15°
30°
A
B
A
B
1-5/8”
13-3/8”
3-7/8”
14-1/2”
-
-
-
-
-
-
2-7/8”
17-3/4”
6-1/4”
18-5/8”
1
-
-
-
-
-
-
-
8-5/8”
22-3/4”
2
-
-
-
-
-
4-1/2”
23-5/8”
9-1/4”
23-3/4”
-
1
-
-
-
-
-
-
11-5/8” 27-7/8”
1
1
-
-
-
-
6”
29-3/8”
12-1/4” 29”
-
-
1
-
-
-
7-1/4”
34”
14-5/8” 33”
-
2
-
-
-
-
-
-
15-1/4” 34-1/8”
-
-
2
1
-
-
-
-
17-5/8” 38-1/4”
1
-
-
1
-
-
-
-
20-5/8” 43-1/2”
-
-
-
-
-
-
10-5/8” 46-3/4”
21-1/4” 44-5/8”
-
-
-
-
1
-
11-7/8” 51-3/8”
23-5/8” 48-3/8”
1
-
-
-
1
-
-
-
26-5/8” 53-7/8”
-
-
-
2
-
-
13-3/4” 58-3/8”
27-1/4” 55-3/4”
-
-
-
-
-
-
15”
63”
29-5/8” 59”
1
-
-
-
-
1
16-1/2” 68-3/4”
32-5/8” 64-1/4”
-
1
-
-
-
1
18”
74-5/8”
35-5/8” 69-1/2”
-
-
1
-
-
1
-
-
38-5/8” 74-5/8”
-
-
-
1
-
1
-
-
41”
78-3/4”
1
-
-
1
-
1
22-3/4” 91-7/8”
44-5/8” 85”
-
-
-
-
1
1
24”
96-1/2”
47”
89-1/8”
1
-
-
-
1
1
25”
103-1/2” 50-5/8” 95-1/2”
-
-
-
-
-
2