Problem with drainage in two new vessel sinks

jpmain

I replaced two vanity sinks with vessel sinks (new counters) and now have a problem with drainage in both sinks. The only change to the drainage plumbing was to increase the length of the down spout to the trap. The total vertical distance to the top of the trap is approximately 12 inches. I have checked the traps for debris, and they are clear.
The water drains in spurts and can be accelerated by stirring the water on the drain with a finger. It does sound like there is an air trap issue but both sinks worked fine before I made the change.

Does anyone have an idea how I can improve the drainage in these sinks?

JP

ChrisDIY

Did the old sinks have overflows?

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--Chris the DIY Guy

Still going, on Ibuprofen...

Alan

Bingo.

I have never installed a vessel sink that did not have this problem. Your overflow acts as a vent for the tailpiece. You no longer have one.

You can try different drain assemblies to help alleviate the problem, but it will never be perfect as it once was.

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Journeyman Plumber

jpmain

Gentlemen,

Thanks for the feedback. I suspected as much but was hoping for some other opinion to support my amateur one. The original sinks did have an overflow and these do not.

Is there a proper way to add a vent to the stack?

JP

Alan

The problem isn't that your drain is or isn't vented. I'd bet it probably is. The water is airlocking in the bowl itself, not necessarily due to a lack of a vent in the drainage system.

I suspect that if you give the water a swirling effect with your hand to create a whirlpool, it will drain properly. Do some searches on different types of vessel drain assemblies and check around to see which ones drain better.

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Journeyman Plumber

JakAHearts

I have this Kraus drain on this vessel sink and have no such problem.

http://www.overstock.com/Home-Garden...9/product.html - Drain

http://www.overstock.com/Home-Garden...9/product.html - Sink

jpmain

Alan, JakAHearts,

Thanks for your input. I did a little more research today and found some indication the problem most likely was caused by the drain itself. The drain has multiple small holes and the surface tension of the water binds in these holes. Having a swirl to the water did make it drain better.

I went looking and found a drain similar to that used by JakAHearts. I have installed these drains and now both drain correctly.

JP

md2lgyk

Wow, I'm glad I stumbled onto this thread. I have the identical problem. My drain also has multiple small holes. Since I did the plumbed the house myself (log home we're building) my wife thinks it's my fault. I'm going to try one of those popups and see what happens.