Hearth and Home Technologies BIR50-B - Manual (Page 26)

26
G. Assemble Chimney Sections
• Attach the first chimney section or offset onto
the top of the fireplace (Figure 8.3). Sheet metal
screws are required to connect chimney section
to the fireplace starter collar. Continue to add
additional sections of chimney as needed.
• Use a wall strap every eight feet of chimney
height.
• For each additional chimney section use four
of the sheet metal screws provided to make a
secure connection between the chimney sections
(Figure 8.4). Do not penetrate the inner liner of
the chimney.
Figure 8.3
Figure 8.4
H. Using 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! Rish of Fire! DO NOT use offset/returns great-
er than 30’. Chimney draft will be restricted and could cause
overheating and fire.
• Measure the shift required to avoid the overhead
obstruction (Offset, Figure 8.5).
• Find the appropriate offset dimension listed in Table 8.2.
• The rise (see Figure 8.5) coinciding with the offset
dimension measurement in Table 8.2 represents the
required vertical clearance needed to complete the offset/
return.
Table 8.2
Elbow
Angle
from
Vertical
Chimney
Length
Between
Elbows
Offset
Inches
Rise
Inches
Offset
Millimeters
Rise
Millimeters
15° 0 2 5/8 21 5/8 67 549
15° 12 in./305 mm 5 1/2 32 1/4 140 819
15° 18 in./457 mm 7 1/8 38 181 965
15° 36 in./914 mm 11 3/4 55 3/8 298 1407
15° 48 in./1219 mm 14 7/8 67 378 1702
30° 0 6 1/4 24 1/2 159 622
30° 12 in./305 mm 11 3/4 34 298 864
30° 18 in./457 mm 14 3/4 39 1/4 375 997
30° 36 in./914 mm 23 3/4 54 7/8 603 1394
30° 48 in./1219 mm 29 3/4 65 1/4 756 1657
RISE
OFFSET
Figure 8.5
Heatilator • Birmingham BIR50-B • 4059-682D • 9/12