Navien NHW700 Installation Manual page 37

3.5.1 About the Vent Installation
Detector
The NHW700 unit comes pre-installed with a Vent
Installation Detector ("VID") to assist the installer in
properly installing the Intake Air/Exhaust Vent Pipe
("Vent Pipe") into the Intake Air/Exhaust vent collar.
How It Works
As shown, the VID is a device connected to the vent
collar which is intended to detect whether the Vent
Pipe has been inserted to a sufficient depth into the
collar during its initial installation.
During installation, the VID detects whether the
vent pipe is fully inserted (at least 1.3 inches or 34
mm) into the collar. If a correctly sized vent pipe (5.0
inch diameter) is fully inserted into the collar, it will
press against a switch to activate the VID. If the vent
pipe is not fully inserted into the collar, the unit will
display an error message and will not operate. Make
sure the vent pipe is correctly sized and has been
inserted properly if Error 762 appears.
Purpose
The VID's purpose is to guide the installer to fully
insert the vent pipe to a depth of at least 1.3 inches
or 34 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.
36 Installing the Water Heater
WARNING
Periodically inspect all vent pipe connections.
The Vent Installation Detector (VID) will NOT
detect the separation of connected vent pipe if
the joints become detached or are leaking flue
gas that may contain carbon monoxide.
The VID is not intended and should not be
relied upon to detect all instances of vent pipe
movement or separation from the collar.
Various factors, including but not limited to
sensor failure, switch sticking and corrosion,
may cause the VID to not properly function if
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.
WARNING
Carbon Monoxide Hazard
To prevent serious injury or death:
ALWAYS insert vent pipe 1.3 in (34 mm) into
●
the water heater exhaust collar.
If the vent pipe is not fully inserted, the vent
●
installation detector switch may not detect
its presence and the water heater may not
operate.