Are PVC unions allowed in a kitchen sink drain line?

[cab1960]

Have an island sink that I would like to plumb with a PVC union in the cabinet so that I could more easily remove the trap and AAV all together as the AAV is tight between the sink and upper part of the cabinet and will be a pain if/when I need to change it.... I know that the trap is considered a "union" type p-trap, so I assume another union is ok, but thought I better check first....Thanks....

 

[FullySprinklered]

You have my blessing. Go for it. Never seen it done, but I'm not aware of any rules against it.

 

[Sponsor]

 

[hj]

WHY would you "need to change it" unless you are redoing the cabinet anyway?

 

[cab1960]

My understanding is that these AAV's may fail and need to be replaced.

 

[Plumber69]

Or just use a mj clamp

 

[hj]

The "normal" instructions just call for it to be 6" above the trap outlet pipe which would NOT be behind the sink.

 

[cab1960]

The "normal" instructions just call for it to be 6" above the trap outlet pipe which would NOT be behind the sink.

It's a large, deep sink. Are pvc unions ok?

 

[Cacher_Chick]

If you want to spend the money on a union. It would be quicker and easier and cheaper to just split the vent riser with a banded coupler.

 

[Terry]

The banded coupling is used quite a bit for plumbing. I woudn't know where to get a union for that.
And yes, they can fail. Being able to replace it is important.

 

[cab1960]

Already have the union. They seem readily available.....I would like to use it in a horizontal position right above the shelf inside the cabinet. Sure makes removing the trap and AAV easy. Unless they aren't allowed, I would like to use it....

 

[Terry]

I would use it then.