Is it OK to have two p-traps in a tub drain?
I have a 2" p-trap built into plumbing in the foundation and a vent right next to the downside of that trap. I am placing a new whirlpool tub that sits right down on the floor and has a 2-1/8" deep drain kit that is below the floor line in the box formed down in the foundation for the drain connection. When I place a 2" elbow90 on the drain pipe at the lowest point and then pipe over and reduce to a 1-1/2" elbow90 with the compression fitting on top that connects to the brass down tube included in the tub drain kit I am too high, so If I use a S trap inplace of the 90-pipe-90 it lowers the compression fitting and gives me the room I need to place the drain kit below floor level. Is having this S-trap above the p-trap going to hinder or cause problems with the tub drain?

Hi Stickshift...

As awful as it sounds, you cannot double trap a fixture and you also cannot use an strap not even by itself.

There have been many many times that I didn't want to but I simply had to cut out the existing trap and move it so it was directly under the tub drain.

You should also remove the floor and install the trap directly under the tub drain assembly.

Mark

Thanks for the confirmation. I was concerned about the effect of double trap and can see where it would create a problem without a vent in between. I am going to search out some smaller radius 90s and find a compression fitting that sits right in

The elbow90 facing up without pipe and an extra fitting. If I cannot find enough there I will simply raise the tub with a 1-1/2" stone foundation to fit the drain. These would be easier than chiseling out a 1/4 yd of concrete to get to trap.