Rinnai CX199i Installation And Operation Manual page 37

1. Direct Vent (Twin Pipe )
Twin Pipe Overview
Intake air and exhaust vent directly through separate penetrations.
Twin Pipe Termination Clearances
Exhaust
12 in. (0.30 m)
Minimum above
intake air
opening
Roof
Figure 24: Twin Pipe Vertical Termination of Multiple
Water Heaters
Rinnai Tankless Water Heater Installation and Operation Manual
Intake
Intake Air
Air
12 in. (0.30 m)
Above grade or
anticipated
snow level
Figure 25: Horizontal Vent and Intake Air Piping
Figure 23
Intake Air
60 in.
min
12 in.
12 in.
min
min
12 in.
12 in.
min
min
Minimum clearance for
Ground/Grade/Snow Level
Indicates area in which intake
cannot be installed.
Exhaust
Intake Air
12 in.
min
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