Reznor SDH Option - Installation - Venting Instructions - Manual (Page 11)

Form I-SDH-V, P/N 211410 R5, Page 11
FIGURE 14 - Concentric Adapter Box, Outdoor Combustion Air Pipe, and Concentric Vent Pipe
Concentric
Adapter Box
Mounting Brackets
X = length of
combustion air pipe required
through and above the roof.
Height from box to top of inlet air
pipe must not exceed 48” (1219mm).
Minimum height above the roof is
18” (457mm) and must be higher
than anticipated snow depth.
FIRST, attach Combustion Air Pipe and Install the
Concentric Box
1) Determine length (X) of pipe (see requirements on the left).
2) Attach the pipe to the collar on the box.
3) Attach the brackets to the roof.
V
ent Flow
22” (559mm) minimum
Cold Climate NOTE:
In geographic areas where
the design ambient is -10°F
or lower, this minimum
height is 34” (864mm).
Collar for Indoor Portion of
the Combustion Air Pipe
Double-Wall Vent Pipe -
Extend length of double-wall
vent pipe a maximum of 6”
(152mm) below the box.
After box is installed, install Concentric Vent Pipe. -
One piece of continuous double-wall pipe must extend from
a minimum of 3” (76mm) above the outer combustion air
pipe to a maximum of 6” (152mm) below the box. (NOTE:
Vent pipe does not attach to the box; it must be supported.)
1) Calculate height (see requirements on the left).
2) Be sure vent flow marking on pipe is in the right direction.
3) Slide pipe through the box and the outer inlet air pipe.
4) Attach to vent run no more than 6” (152mm) from the
adapter box. See instructions in FIGURE 3, pages 3-4.
Vent pipe
extending
through the
box and the
combustion
air pipe MUST
be one continuous
piece of double-
wall vent pipe.
A second section
of double-wall pipe
is permitted, joining
the long continuous
piece of vent pipe a
minimum of 3” (76mm)
above the top of the
combustion air pipe.
3” (76mm)
minimum
If needed, add a second section of double-wall pipe to
comply with the height requirement on the left.
Determine the minimum length by adding the requirements. Starting at the bot-
tom, the maximum the vent pipe can extend below the box is 6” (152mm); plus 6”
(152mm) through the box; plus length of bracket extending above the box; plus the
width of the roof; plus the height of the outside combustion air pipe above the roof;
plus a minimum of 3” (76mm) beyond the top of the inlet air pipe. Total is the mini-
mum length of the one-piece double-wall vent pipe section. If the actual piece of vent
pipe is longer, extend it higher above the combustion air pipe. Do not extend it more
than 6” (152mm) below the box.
b) Install the pipe. Being sure the pipe is in the proper flow direction, slide the end
into the box and out through the combustion air pipe. Position the vent pipe so that
the end is no more than 6” (152mm) below the box. The upper end should extend at
least 3” (76mm) above the combustion air pipe. NOTE: The double-wall vent pipe
does not attach to the box. The installer must provide support.
Follow the instructions in
FIGURE 3, pages 3-4, for connecting the double-wall pipe
to the vent run (single-wall pipe, Category III pipe, or taper-type connector).
Seal the circumference of the pipe and the opening of the box with silicone sealant.
Seal the area around the pipe completely.
7. On the outside, if an additional section of double-wall pipe is needed (See
FIGURE 16), add it. Make joint according to the pipe manufacturer’s requirements.
When vent pipe is the required height, slide the combustion air inlet over the vent
pipe and fasten the collar to the combustion air pipe with sheetmetal screws. Seal the
opening at the top between the vent pipe and the combustion air inlet with silicone
sealant to prevent water leakage.
8. Attach the exhaust (vent) cap. Follow the illustrated instructions in FIGURE 2,
page 3.
9. Attach the indoor combustion air pipe. Use sheetmetal screws to attach the
single-wall combustion air pipe run to the collar on the concentric adapter box. Seal
with tape or sealant. If installing a Model SDH Size 150, field-supplied taper-type 5”
to 6” (127mm to 152mm) reducer is required to connect the combustion air pipe to
the collar on the box. See FIGURE 8, page 6.
Outside view with
concentric adapter box
attached to underside
of roof. Install field-
supplied flashing at
roof opening.
18” (457mm)
minimum
(or higher if
snow clearance
is needed)
(NOTE: Maximum
from concentric
adapter box is
48” (1219mm.)
Combustion
Air Pipe
FIGURE 15 - Slide
attached Combustion
Air Pipe up through the
Roof