HELP! Is this sink plumbing done correctly?

[stuartjbecker]

We are new homeowners and all things plumbing are a bit new to me. Looking under the kitchen sink there seems to be an interested configuration of pipes.

At the top, it is hard to see but there is an Oatey Air Admittance Valve.

Does this setup look done correctly? We have had some some trouble with the sink draining in a timely manner....

Thanks for your help!
~Stuart

 

[frodo]

Ugly,,,,very very ugly..

 

[frodo]

http://ecx.images-amazon.com/images/I/31KZBNNsQZL._SX425_.jpg

st 45..............

 

[Matt30]

What a mess!

 

[stuartjbecker]

Thank you! That's perfect

 

[Zanne]

Yikes. That is NOT good. As a general rule, you need to have the vent pipe (the one with the AAV) at or before the vertical drop from the trap arm. What you have there is an S-trap. This makes it hard for the air pressure to equalize and can result in a vacuum. On one hand, it can make things drain slower but it can also siphon water out of the trap and allow sewer gases to come up through the sink.

In an ideal system, your trap arm would extend in to the wall where there would be a vent pipe that meets up with the main vent stack somewhere up high. AAVs are actually banned in at least one state because of the possibility of failure.

Keep in mind that the pipe from the garbage disposal needs to have a downward angle toward the drain from the sink basin. It is important to let gravity pull the water and waste out of the disposal or it can get stuck-- but make sure that its not too steep-- the drop should not exceed one pipe diameter.