Vessel bowl basin slow drainage problem

[JMCC]

Hello all,

I just installed a vessel bowl basin in my bathroom and it looks great. However, it doesn't drain adequately. The bowl would actually overflow if I left the water running. I shortened the tail piece to see if it would help and it didn't.

I thought the problem might be the lack of an overflow on the basin, but the sink in the kitchen doesn't have an overflow and yet it drains fine. Nevertheless, would a pro-vent help?

It does have a 19-hole drain with no stopper. Could this be hamplering the flow?

Any and all advice would be welcome.

Thanks,

JMCC

Vessel bowl basin slow drainage problem

[jimbo]

Grid drains are notorious for this. Try drilling out 5 or 6 holes to about 1/4" or 9/32" diam.

[hj]

You are being air-locked by the bubble between the trap and the strainer. The openings in the strainer are not large enough for the air to escape AND let the water drain down at the same time. It is compounded by the strainer being flat so that there are no pressure differentials created. A domed strainer or larger holes will cure the problem.

[Redwood]

Some of the worst ideas in plumbing survive by being "Oh So Fashionable"

[JMCC]

Well, I replaced the 19-hole grate with a 15-hole one with larger holes. Not good enough. I then drilled out 6 of the holes to .25". Still not enough. I finally drilled out the 6 center holes to .3125" and that did the trick!
Thanks for the advice hj and jimbo.

[Terry]

The drain by Mountain Plumbing Products works better with vessel bowls without the overflow.

http://mountainplumbing.com/mt749

[JMCC]

And it's very nice looking too!
Thanks!

[rickparsons]

I have a vessel sink that drains slowly. I figured it was the lack of positive pressure. I have a pop up drain with just two small oval openings for water and air to go through. Any recommendations on how to get past this problem on a sink with no overflow? Thanks.