Rinnai RU98e Installation And Operation Manual page 15

Flue Installation with Concentric Venting (indoor models only)
Install the venting termination according to the diagrams and instructions below.
Slope the venting toward the appliance according to
the vent manufacturers installation instructions.
Dispose of condensate per local codes.
Horizontal Termination
Vertical Termination
Slope the venting toward the appliance according to
the vent manufacturers installation instructions.
Dispose of condensate per local codes.
Securing Screw
KB Series Manual
Secure the first vent component to the water heater
with one self-tapping screw at the hole.
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