Rheem PowerVent Series Use & Care Manual page 16

Installing the water heater
16
Additional Venting Requirements
Installations requiring less than one (1) foot of vertical pipe before the first elbow, subtract six
(6) feet from the maximum vent length.
Less than 1 ft.
vertical pipe
before first
elbow
Minimum Vent Restrictor
Install the vent restrictor only at the minimum vent lengths listed on page 15.
Vent Pipe
DO NOT use the vent restrictor for any other vent lengths.
Additional PVC Fittings Considerations
DO NOT Use
Short Sweep 90° Elbow
Vent Restrictor
Mesh
Vent Terminal
Good
Standard 90° Elbow
Best
Long Sweep 90° Elbow