32
Rinnai Commercial Hybrid System Installation and Operation Manual
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.
•
For use with CU199i internal (indoor) tankless water heaters only.
Header
Vent Length
Common Vent Maximum Equivalent Vent Lengths
Common Vent Maximum Equivalent Vent Length
Rinnai Common Vent System or Schedule 40 PVC/CPVC
Water Heater
Model
# Water
Heaters
Max System
BTU/HR
HEADER DIAMETER
3 in.
4 in.
6 in.
3 in.
Vent Diameter
4 in.
Vent Diameter
6 in.
Vent Diameter
6 in.
Vent Diameter
CU199i
(REU
-
N3237FFC
-
US)
2
398,000
65 ft
150 ft
150 ft
150 ft
3
597,000
4
796,000
65 ft
5
995,000
6
1,194,000
7
1,393,000
70 ft
8
1,592,000
