Air Admittance Valve Help

[jjones2]

Are air admittance valves allowed in the main drain pipe like this?

Home is only 5 yrs old. Kitchen has AAV installed correctly but this one for the tub just seems like a potential for sewer leakage in the event of a backup!

Thanks in advance for the help

John

[Gerry Pallotta]

John
It seems to be o.k. there, but here is some more info.
http://www.toolbase.org/pdf/techinv/aavs_techspec.pdf

[Russell J. Hensel]

Hope this helps

[Gerry Pallotta]

Hi John
Here is the actual code.

3114.4 Location

Individual and branch air admittance valves shall be located a minimum of 4 inches (102 mm) above the horizontal branch drain or fixture drain being vented. Stack-type air admittance valves shall be located a minimum of 6 inches (152 mm) above the flood level rim of the highest fixture being vented. The air admittance valve shall be located within the maximum developed length permitted for the vent. The air admittance valve shall be installed a minimum of 6 inches (152 mm) above insulation materials installed in attics.
http://www.studor.com/codes.htm

[jjones2]

Thanks for the help guys, I called it an untypical installation and review by a Qualified Plumber is recommended.

Thanks again

John