Navien NFC-175 Installation & Operation Manual page 59

For cascade applications, the required horizontal
Note
clearance between terminations is 12" for both sidewall
and vertical venting installations.
Indoor Boiler Installation Venting Examples (Continued)
Low Profile Two-Pipe Sidewall Venting*
●
Intake Air
(from
outdoors)
Exhaust
(from
appliance)
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
Only the following orientations are allowed for twin
Note
pipe terminations.
Do not vertically stack
concentric terminations on
sidewalls.
Flexible Vent Systems (Polypropylene)
●
Only VERTICAL installations are allowed. Horizontal
Note
●
terminations are prohibited.
The use of proper adapters and supports are required
●
to fully complete the installation.
The following table lists the flexible vent models that are approved
for use with this appliance in addition to the maximum allowable
vent lengths for the desired vent system.
Model Type Vent Dia.
NFC-175/200 2 in
Only the flexible vent models listed above are approved for use
●
with this appliance.
All flexible vent pipe must be installed VERTICALLY through the
●
roof. No horizontal terminations are permitted.
Use a 2 in snap fit coupler or the InnoFlue® Single Wall
●
Residential vent pipes to connect the InnoFlue® Flex 2 in vent
pipes to the exhaust.
After installation, ensure that the vent system is tightly sealed at
●
the joints.
All installation using the flexible vent materials must be in
●
INDIRECT VENTING only.
Refer to the manufacturer's literature for detailed information
●
and guidelines.
Flexible PP
Centrotherm Innoflue Flex
50 ft
Venting the Boiler 59