Shower drain

[goldspur]

2 inch horizontal drain back vented with 1&1/2 inch to main stack with wye & 45.what is the reason for disallowing the use of a TY to elliminate the 45?could have found the ans. reading previous posts but most posters talk in code (the other code),like what part of the fitting is the back or heel?
Thank You..
goldie.

 

[Redwood]

The answer is quite simple...
The horizontal drain requires the use of a wye and 45 or, a combo.

 

[Sponsor]

 

[hj]

Ty

Actually, if you cannot see the reason by looking at the two different fittings, maybe you should not be doing the job. The TY, assuming you are referring to a sanitary tee and not a combination Y-1/8 bend, has negligable sweep and the code specifies the amount of sweep for ANY fitting below the overflow level of the fixture. If you are refering to a combo, then it is the same as a Y and a 1/8 bend/45.

 

[Terry]

Both of these can be used on the horizontal

The SanTee can not be used on it's back.
It has to be vertical.