Maintenance - Navien NFB-175H Installation Manual

9.8 Maintenance

Periodically check the damper condition inside the
Common Vent Collar Kit through the maintenance
port to ensure optimal performance of the system.
Follow the instructions to check the damper
condition and replace the Common Vent Collar Kit if
necessary.
1. Remove the screw that fixes the maintenance
port cover to the Common Vent Collar Kit, and
then remove the gasket and the maintenance
port cover.
Gasket
Maintenance port cover
Fix screw
2. Through the maintenance port, check the
operating condition of the damper plate inside
the Common Vent Collar Kit.
90 Installing a Common Vent System
3. Reinstall the gasket and maintenance port
Note
Maintenance
port
4. Visually inspect the maintenance port to ensure
Ensure that the gasket is properly installed
under the maintenance port cover, after
checking the operating condition of the
damper plate through the maintenance port.
Harmful exhaust gas may leak if the gasket is
not installed, or if it is not installed properly.
Damper
plate is
CLOSED.
Damper
plate is
OPEN.
cover, and then fix them with a set screw.
If condensate comes out the port when
opened, check for proper drainage or
any blockage.
that the gasket is properly installed between the
maintenance port and the maintenance port
cover.
WARNING
Gasket