Navien NFC-250/175H Installation Manual page 66

Purpose
The VID's purpose is to guide the installer to fully
insert the vent pipe to a depth of at least 3.0 inches
or 76 mm, into the collar. If the vent pipe is not
properly inserted and installed, it could separate
from the collar resulting in flue gas spillage and
carbon monoxide emissions which will result in
severe personal injury or death.
WARNING
The VID is not intended and should not be relied
upon to detect all instances of the vent pipe's
vertical movement or separation from the
collar. Various factors, including but not limited
to sensor failure, switch sticking and corrosion,
may cause the VID to remain activated after the
vent pipe separates from the collar.
Limitations
The VID is not an alarm, safety switch or a substitute
for a carbon monoxide detector. The VID may not
cause the unit to stop operating if the vent pipe
is partially or completely dislodged. Other factors
can impact the performance of the VID causing
it to be unable to function as intended. Such
factors include, but are not limited to, deformity
of the vent pipe, not using a correctly sized vent
pipe, misalignment of the vent pipe into the collar,
vertical movement of the vent pipe caused by
improper installation, and other misuse or non-
conformance with installation instructions.
66 Venting for Combustion Air
WARNING
The list above does not represent an
●
exhaustive list of situations that may prevent
proper operation of the VID. It is the installer's
responsibility to install the vent pipe properly
and to adequately secure the unit to the wall.
The vent pipe must be inserted 3.0 in (76 mm)
●
into the boiler collar. If the vent pipe is not
fully inserted, the vent installation detector
switch will detect it and the boiler may not
operate. Make sure that the pipe is inserted
properly and that only the correctly sized
vent pipe materials are used or an error code
E762 can appear on the front panel.
The failure to properly install the vent pipe
●
into the boiler collar or using incorrectly
sized vent pipe materials in strict compliance
with installation instructions may cause the
vent pipe to separate from the boiler which
will result in excessive carbon monoxide
emissions and extremely
conditions which can lead to severe personal
injury and/or death.
Be sure to conduct a visual inspection of the
●
vent pipe before inserting the vent pipe into
the boiler collar. The portion of the vent pipe
inserted into the boiler collar must be free
from damage or defects in order for the vent
installation detector to operate properly. If
the vent pipe is damaged, then replace it with
new vent pipe. The vent installation detector
only detects separation of the vent pipe from
the boiler collar if fully inserted 3.0 in (76
mm). The vent installation detector will not
detect the separation of connected vent pipe
if the joints become detached.
dangerous
3.0" (76 mm)