A concentric venting system may be the best option for use with many types of water heaters, including direct and power direct vent as well as tankless. While the material of a concentric vent may differ depending on the type of water heater you have, this aesthetic installation option refers to any coaxial “pipe in pipe” design. This means simply that the intake air and exhaust gas move through separate chambers of the same assembly.
For water heating units, such as direct vent or concentric vent tankless, concentric venting may be used for the entire vent run, from the water heater to outside the home.
Concentric vent terminations offer the aesthetic benefits of a single wall or roof penetration, and they can be used with power direct vent or tankless water heaters. For these installations, separate pipes for intake and exhaust run between the water heater and inner wall, and concentric piping is used only for the wall penetration and termination.
For installation of concentric venting, we recommend that you consult a professional plumbing contractor