Navien NPN Installation & Operation Manual page 35

WARNING
The vent pipe must be inserted 1.3 in (34
●
mm) into the water heater collar. If the vent
pipe is not fully inserted, the vent installation
detector switch will detect it and the water
heater 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 water heater collar or using
incorrectly sized vent pipe materials in strict
compliance with installation instructions
may cause the vent pipe to separate from
the water heater which will result in excessive
carbon monoxide emissions and extremely
dangerous 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 water heater collar. The portion of
the vent pipe inserted into the water heater
collar must be free from damage or defects
in order for the vent installation detector
to operate properly.
damaged, then replace it with new vent pipe.
The vent installation detector only detects
separation of the vent pipe from the water
heater collar if fully inserted 1.3 in (34 mm).
The vent installation detector will not detect
the separation of connected vent pipe if the
joints become detached.
34 Installing the Water Heater
If the vent pipe is
1.3" (34mm)
WARNING
The vent
installation
detector
Undetectable
Detectable