Rinnai Demand Duo CX Series Installation Instructions Manual page 34

For the table below:
•
Header is the main vent pipe into which
several vents connect
•
Vent Length is the distance from the end of
the header to the vent termination.
•
Maximum vent length starts at the end of the
header system.
•
Use 10 ft (3 m) as equivalent vent length for
90° elbows.
Table 15
Common Vent Maximum Equivalent Vent Length
Rinnai Common Vent System or Schedule 40 PVC/CPVC
Water Heater
Model
CX199i
(REU-N3237FFC-US)
CX160i
(REU-N2530FFC-US)
Demand Duo H-Series with SENSEI CX Installation Instructions
Max
# Water
System
Heaters
BTU/HR
2 398,000
3 597,000
4 796,000
5 995,000
6 1,194,000
7 1,393,000
8 1,592,000
2 320,000
3 480,000
4 640,000
5 800,000
6 960,000
Figure 40
Header
HEADER DIAMETER
3 in.
3 in. 4 in.
Vent Vent
Diameter Diameter
65 ft
150 ft
65 ft
90 ft 150 ft
100 ft
65 ft
Vent length
4 in. 6 in.
6 in. 6 in.
Vent Vent
Diameter Diameter
150 ft
150 ft
70 ft
150 ft
150 ft
34