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90 Installing a Common Vent System
3. Reinstall the gasket and maintenance port
cover, and then fix them with a set screw.
Note
If condensate comes out the port when
opened, check for proper drainage or
any blockage.
4. Visually inspect the maintenance port to ensure
that the gasket is properly installed between the
maintenance port and the maintenance port
cover.
WARNING
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.
Gasket
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.
Maintenance
port
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.
Damper
plate is
OPEN.
Damper
plate is
CLOSED.
Summary of Contents for NFB-175H
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