Air Admitance Valve

Is it acceptable to install an AAV in any position other than vertical? Unable to determine brand so I cannot search installation instructions by manufacturer. Any help would be appreciated.

Most of the time it should be on the horizontal line mounted on a vertical stem.

Read hear. http://rds.yahoo.com/_ylt=A0oG7laLveVM6PkAHzFXNyoA;_ylu=X3oDMTE1MWE0anByBHNlYwNzcgRwb3MDMQRjb2xvA2FjMgR2dGlkA1ZJUDAzMV8xODE-/SIG=11sshk7am/EXP=1290211083/**http%3A//www.studor.com/DesignCriteria.pdf

The UPC forbids their use all together, I believe. Check to see which plumbing code the applicable jurisdiction has adopted.

You are correct Jim, and forgot to say that. They are illegal to use in Maine unless for a renovation of existing conditions and approved by the AHJ.
Thanks for picking up on that. :slight_smile: