pipe layout question?

[massivegalaxy]

Hi
i have question about this pipe layout. now looking at picture on web you can't connection drain pipe to vent stack using wye cause it can suck the water out of the p trap. so you add sanitary tee to sawyer drain.
so is there problem adding 90 elbow then 2 inch straight pipe down then hook up with wye tee to sewer pipe?
here a diagram of what I'm taking about.

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[James Henry]

That doesn't work. Why do you want to do it like that?

 

[Sponsor]

 

[GReynolds929]

Yes there is a problem. That's worse than using a wye instead of a Santee. Why would you not use the proper fitting?

 

[massivegalaxy]

ah ok. because my dad 20 years was remodeling the bathroom and that how he hook up the bathtub drain part to vent stack. now we haven't use the tub at all in fact few years ago we got in put in but never used it. not all glue in. so it can be resigned.