New P trap not draining

[waynereg]

Broke the previous tail going into the floor while installing the new vanity in the bathroom.

I used a new S trap kit to connect where the tail had previously broken off at the B nut going into the drain.
The configuration looks very similar to the one I removed but now it takes 40 minutes for a few inches of water to drain. Everything is new and clear.
My set up drains strait down into the cement slab where the drain is unlike most P traps that seem to head to the rear and into the wall, this one goes strait down. Is there an issue with air being trapped? could anyone draw up a different way to connect?

 

[Jadnashua]

That configuration will never work great, and does not meet current (or any previous) plumbing code!

First, you can't stack two traps together in any fixture.

Second, you have sort of a double S-trap, which isn't to code, either.

To fix this, maybe the easiest would be to use a conventional P-trap and use an air admittance valve (AAV).

This shows the general idea of how it is done https://www.bhg.com/home-improvement/plumbing/how-to-install-air-admittance-valve/

The p-trap can be rotated to give you a bit of clearance and the riser with the AAV should go up as high as possible in the sink cabinet and still be able to unscrew it for replacement down the road. If it's too low, it can be fouled by waste if there's a backup. You could cut off the downpipe attached to the sink to give you a bit more room, too.

 

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[hj]

Unless there is also a trap under the floor, this is a SINGLE "S" trap, but ANY obstruction in the drain downstream will prevent drainage because of an air blockage. If that is the cause an AAV will NOT give better drainage.