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67
Venting for Combustion Air
Indoor Boiler Installation Venting
Examples (continued)
●
Low Profile Two-Pipe Sidewall Venting*
Exhaust
(from
appliance)
Intake Air
(from outdoors)
12”
(300 mm) min.**
Exterior View
* IPEX and Centrotherm Low Profile terminations
only
** Clearance above highest anticipated snow level
or grade, or as required by local codes, whichever
is greater
Note
Only the following orientations are
allowed for twin pipe terminations.
●
Concentric Sidewall Venting
1" (25 mm) min.
Combustion Air intake
Combustion
Air intake
Maintain 12" (300 mm) min. clearance above highest
anticipated snow level or grade, whichever is greater
Exhaust
Gas
Exhaust
Gas
●
Concentric Vertical Venting
Combustion
Air intake
Maintain 12” (300mm) min.
clearance above highest
anticipated snow level or
grade, whichever is greater
(maximum of 24” above
roof)
Exhaust Gas
Note
For cascade applications, the required
horizontal clearance between
terminations is 12” for both sidewall and
vertical venting installations.
Do not vertically stack
concentric terminations
on sidewalls.
Summary of Contents for NFB-175H
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