AAV installation

[lprinzi]

I ran across this today and never saw it before. It appears to be an Air Admittance Valve(??) installed on the end of a vent stack. Anyone have info on if this is a proper installation? Thanks

[ldapkus]

www.airadmittancevalve.com

[lprinzi]

What is that link supposed to tell me?

[Jeffrey R. Pope]

I doubt it's actually an AAV. It looks like a cap of sorts, but I'm not sure why it's there.

Installing an AAV in such a manner would completely defeat the purpose for having an AAV to begin with. . .

[Mark Thorman]

I have recently started seeing these here on maui. They are always on homes with a septic tank and typically high wind areas although no has a good explaination for them. I though maybe to prevent back pressure on traps?

Mark Thorman
Thorman Home Inspections
www.mauihomeinspections.com

[Jack L. Gilleland]

Never seen one used that way. If there are high winds in the area the some plumbers put a hook - upside down trap to keep the wind from blowing the traps in the house.

[Mark Thorman]

I thought it was a Maui thing. Things get done a little differently here.

Mark Thorman
Thorman Home Inspections
www.mauihomeinspections.com

[lprinzi]

Thanks for the responses. It kinda stumped me too. The installation is on a home without a septic but it is in St. Augustine, Fl. Maybe the high wind theory is the reason, but it's only installed on one vent.