Need help with drainage for sinks

[David Romanyshyn]

My wife and i purchase our house three years ago and been updating ever since. We started the bathroom last week. We are changing it drom a single sink to a double. Ran all new plumbing for it and now having issues. Both sinks drain very slow. I try to add a trap with a vent and also a studer vent on the other sink and still hasn’t helped. What else can i do

 

[Reach4]

Stick a plastic soda straw a few inches down the drain as you drain water. This lets air come out. Does the flow improve a lot?

 

[Sponsor]

 

[David Romanyshyn]

Stick a plastic soda straw a few inches down the drain as you drain water. This lets air come out. Does the flow improve a lot?

That didn’t work. Seems like If i use a plunger it helps it

 

[Plumber69]

unscrew the popup drain and try. Also take the studor vent off and try

 

[David Romanyshyn]

I had it without a studer vent and pop up drain to start and that didn’t work

 

[David Romanyshyn]

Does it matter how far the tailpiece goes into the trap?

 

[Reach4]

Does it matter how far the tailpiece goes into the trap?

It must go in far enough to not leak. Other than that, no.

Your symptoms seem strange. It did not work with the stopper removed. As you fill the sink, does the water rise in the bowl 2 or 3 inches, and then suddenly clear the bowl?

How about a partial blockage in the wall in a drain line common to both sinks? If that was the case, position a bucket under sink A. Remove the bottom of the p-trap that is over the bucket. Flow water into the other bowl (B) should make water leak out where the removed p-trap was.

If drain B drains fine but no water leaks from trap A, that would indicate something else.

 

[Terry]

Does it matter how far the tailpiece goes into the trap?

Yes, It can't be too long. I would thing from looking at your pictures that your tailpiece is too long on the trap with the AAV built into the trap.

Basins without an overflow sometimes have issues with draining. They do make some pop-up drains that work for that. Kohler makes a nice one that works.