Venting Options; Direct Vent (Concentric And Twin Pipe); Non-Direct Vent (Room Air) - Rinnai I Series Installation And Operation Manual

Two venting options are available: Direct Vent and Non-Direct Vent (Room Air).

Direct Vent (Concentric and Twin Pipe)

Option 1
See the Direct Vent section for complete details.
Concentric Pipe
Combustion air and exhaust vent directly
through a single concentric connection. Hot
exhaust exits through the interior pipe,
while combustion air enters through the
outer pipe.
Exhaust
Combustion
air
Option 2

Non-Direct Vent (Room Air)

See the Non-Direct Vent section for complete details.
Room air is used for combustion
while exhaust vents to the outside.
Rinnai I-Series Condensing Boiler Combi Manual
Combustion
air
Combustion
air
Twin Pipe
Combustion air and exhaust vent
directly through separate penetrations.
Exhaust
Combustion
air
Exhaust
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