kitchen sink clogged

[nik-_rad]

kitchen sink is clogged but as soon as I open the AAV (vent ) under the sink, the water drains well. No other clogging noticed in any other sinks/toilets.

Thoughts ? Ideas ?

 

[SamirD]

Which side is clogged?

 

[Scarpozzi]

You're solving the drain issue by opening a vent. Once the water goes into the wall, the pipe splits....the water travels down and the air vents up and out the top of the wall. There's a chance something is plugging your vent line (birds nest, dead squirrel, etc). That could be causing the drain to be slow and causing enough vacuum for it to backup and slowdown even further.

 

[JEDIYoda]

its okay to vent about these things.....

 

[Scarpozzi]

its okay to vent about these things.....

If you have along enough garden hose, you can check for a blackage from the roof....but if it's something obscure, it may take an auger to break down whatever it is. Those vent pipes are usually on 1.5-2" in diameter, but may go into a 3-4" main drain line (below the sink).

 

[Greenman]

Shouldn't work that way. If the AAV isn't working the trap should get sucked dry.

You're solving the drain issue by opening a vent. Once the water goes into the wall, the pipe splits....the water travels down and the air vents up and out the top of the wall. There's a chance something is plugging your vent line (birds nest, dead squirrel, etc). That could be causing the drain to be slow and causing enough vacuum for it to backup and slowdown even further.

The valve under the sink is almost certainly the only vent on the line. If it was properly vented there wouldn't be any reason for the air admittance valve. Hokey way to plumb, but I guess it works.

 

[Scarpozzi]

Shouldn't work that way. If the AAV isn't working the trap should get sucked dry.

The valve under the sink is almost certainly the only vent on the line. If it was properly vented there wouldn't be any reason for the air admittance valve. Hokey way to plumb, but I guess it works.

Wouldn't that allow air to flow up the line when the vent is open and introduce lovely gray-water smells under your sink? I assumed that was there in-addition to a standard vent exhaust line to the outdoors like most code books require. (unless we're dealing with a 3rd world situation like Canada or West-Virginia)

 

[Greenman]

Wouldn't that allow air to flow up the line when the vent is open and introduce lovely gray-water smells under your sink? I assumed that was there in-addition to a standard vent exhaust line to the outdoors like most code books require. (unless we're dealing with a 3rd world situation like Canada or West-Virginia)

Think of it as a check valve, air (or waste water) only moves through it one way. They're used when there is no way to run a proper vent, or your plumber sucks and is lazy.
I've never actually seen one in use, but I believe they are legal in some places. There have been a few times that I wished I could use one, would have saved several days of cutting, drilling, and patching. Tragically, I'm not a lazy suckey plumber.

 

[Scarpozzi]

Think of it as a check valve, air (or waste water) only moves through it one way. They're used when there is no way to run a proper vent, or your plumber sucks and is lazy.
I've never actually seen one in use, but I believe they are legal in some places. There have been a few times that I wished I could use one, would have saved several days of cutting, drilling, and patching. Tragically, I'm not a lazy suckey plumber.

Plumbing isn't something you want to do wrong. The waste-water side doesn't have a valve you can easily turn off when things run backwards....I've seen it go uphill before (despite what the old adage claims).

 

[Micrornd]

How about a simple solution - If the drain has been functioning properly and still functions properly when you open the AAV, then the AAV is defective, replace it.

 

[Mark Steve]

A vent is a fundamental aspect of the channel framework for any pipes installation. Without venting, the negative weight brought about by the progression of depleting water can possibly drain water out of the channel trap and permit sewer gases to enter the home. The vents permit air into the channel lines to help keep the channel streaming appropriately.