Offset Elbow Installation; Supplementary Support & Stabilizer - Heatilator BIR50-B Installation Manual

I. Offset Elbow Installation
A 30° Elbow (measured from the vertical) is the largest
that can be used in an offset. A 30° Elbow may not be
combined with another Elbow to make a steeper offset
(e.g. two 30° Elbows are not allowed to be put together to
form a 60° elbow.). Avoid Elbows if possible. A totally ver-
tical chimney is more efficient. When Elbows are neces-
sary to avoid obstructions such as rafters, ridgepoles, or
joists, you are only allowed to use 2 pair of Elbows in any
one chimney system. Horizontal runs of chimney violate
building code and are not allowed.
• Attach elbows
Attach elbow to chimney section or other elbow by
mating the male and female ends with each other and
using four sheet metal screws provided. Attach one
elbow to the chimney section below, and align it for the
offset. Determine the required offset length and attach
an appropriate length (or lengths) of chimney section(s)
above the elbow. Attach the second elbow above the
chimney section to complete the offset (Figure 4.6).
• Secure offset
Use an elbow strap to secure the offset. Secure the
elbow strap's band to chimney around the upper portion
of the top elbow, then tighten the nut and bolt until the
clamp is firm. Wrap the elbow strap end over an adjacent
joist or rafter and secure it with at least two 8-penny nails
or two #8, 1-1/2" screws. Add additional elbow straps
for each section of chimney in the offset (Figure 4.7).
Every chimney section in the offset must be supported.
Do not add more chimney sections until the elbows and
offset are supported. Be sure that the chimney remains
vertical.
Elbow Strap
30° or 15°
Elbow
Figure 4.6
Heatilator • Birmingham BIR50-B Installation Manual • 4059-701 • Rev G • 06/29/15
Elbow Strap
1 per
Section
Figure 4.7
J. Supplementary Support & Stabilizer
Install a supplementary support if total chimney height
is greater than 50-feet, or if the fireplace manufacturer
requires it. If additional support is needed, install one or
more supplementary supports which can each support 25-
feet of chimney (Fig. 4.8).
• Clamp the supplementary support band around the pipe
using the nut and bolt provided, and anchor the support
to nearby building framing.
• Always maintain the 2" clearance to combustibles from
the chimney pipe. A stabilizer is available and may
be required by some fireplace manufacturers to keep
the chimney vertical and help maintain clearances to
combustibles within a chase.
• Clamp the stabilizer to the pipe using the nut and bolt
provided, and secure legs to nearby framing using
plumber's tape or guy-wires (Fig. 4.9).
Note: The stabilizer does not support the weight of the
chimney, it is only used to keep chimney centered within
a chase.
Install supplementary
support if height exceeds
50 ft or if required by
fireplace manufacturer
Figure 4.8
Plumbers
Tape
Figure 4.9
Each supplementary
support holds up to
25 ft. of chimney
Maintain 2 in. clearance
from chimney to framing
Chase
Frame
Stabilizer
19