2889Please see attached picture. My question is about the fitting where the trap arm connects with the vent line. I would like to use a sanitary tee in order to be able to maintain the proper pitch for water to run. I am unable to maintain pitch if use the sanitary tee vertically. I have read that a sanitary tee cannot be used horizontally, but in this case it seems to me to be more vent than drain. Any thoughts would be helpful.

Thank you

What you want use for what you have drawn is a 2" combo.

It's basically a 2" Wye with a 2" 45 added to make the Wye portion truly vertical.

The trick here is this. A vent must rise on a minimum of a 45 degree rise for a dry vent and can not be greater than a 45 degree rise until you get at least 6 inches above the flood level rim of the fixture it serves. A tee or 1/4 bend can not lay on its side or back.
However, on a setting like inside a ceiling you can run a dry vent horizontally. The inspector will cringe but allow it. On your layout I suggest a 2" wye or combination horizontally to use a sweep to rise. It allows you the depth and stay legal.