Navien NHB-055 Installation & Operation Manual page 64

9.3.2 Connecting the Pipe to the Damper
1. Insert 2" vent pipe to the backflow damper to start the vent
run.
2. Completely slide the vent pipe ends into the transition fitting.
Tighten the clamp with a screwdriver to properly seal the joint.
64 Installing a Common Vent System
9.3.3 Assembling the T Joint
1. Connect an 8"-to-2" reducer to the 8" tee. Apply solvent
cement to the mating surfaces.
Apply
Cement
Multiple reducers can be used to allow proper
Note
connection of 2" vent pipe to the common vent
system.
2. Assemble the tee joint assembly (8"-to-2" reducer + tee joint)
to the vent pipe. Apply solvent cement to the mating surfaces.
Apply
Cement
8"-to-2" reducer