Rinnai Tankless Water Heater Installation and Operation Manual
41
This configuration requires the use of a Concentric Vent
Termination
2 in. or 3 in. PVC/
CPVC IPEX/ Royal
Concentric Side Wall
Termination Configuration
This configuration requires the use of a Concentric Vent
Termination
2 in. or 3 in. PVC/CPVC
IPEX/ Royal Concentric Vertical
Termination Configuration
2 in. or 3 in. Schedule
40 PVC/CPVC or ABS Snorkel
Termination Configuration
2 in. or 3 in. Schedule 40
PVC/CPVC or ABS Standard
upside down “U” Vertical
Termination Configuration
2 in. or 3 in. Schedule
40 PVC/CPVC or ABS Elbow
or Tee Side Wall
Termination Configuration
2 in. or 3 in. Schedule
40 PVC/CPVC or ABS Tee
Vertical Termination
Configuration
2 in. or 3 in. PVC
Low Profile Termination
Configuration
Exhaust and
combustion air
MUST NOT be
brought together
into a single
PVC pipe using
a pipe fitting.
1. Direct Vent
(Twin Pipe)
Twin Pipe Example Vent Applications
Slope horizontal exhaust 1/4 in. per foot towards the water heater. DO NOT slope combustion air pipe
towards the water heater.
Single
Pipe
Combustion
Air
Exhaust
Twin Pipe Maximum Vent Length
Table 17: Twin Pipe Maximum Equivalent Length
Vent Sizes
2 in. (51 mm) 3 in. (76 mm)
Vent Lengths
65 ft (20 m)
150 ft (46 m)
•
45° elbow is equivalent to 3 ft (1 m)
•
90° elbow is equivalent to 6 ft (2 m)
Table 16
WARNING
