Rinnai ThermaCirc360 RUR199i Installation And Operation Manual page 27

1
Direct Vent
Concentric Pipe Overview
Combustion air and exhaust vent directly through a single
concentric connection. Hot exhaust exits through the interior
tube, while combustion air enters through the outer layer.
Concentric Pipe Termination Clearances
12 in.
(0.30 m)
Inside
Corner
All terminations (horizontal and/or vertical) must terminate 12 in. (0.30 m) above grade or anticipated snow level.
Rinnai Tankless Water Heater Installation and Operation Manual
(Concentric Pipe)
12 in.
(0.30 m)
60 in. (1.52 m) vertically
between terminals
Exhaust
Combustion
air
60 in. (1.52 m)
Note: 24 in. (0.61 m)
to wall or parapet
Between terminals at different levels
12 in. (0.30 m)
Between terminals at same level
Combustion
air
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