No Main Vent and Wet Return replacement

ranzerox

Happy holidays!

I'm looking for advice on a system with no Main Vent and replacing the Wet Return please. The system EDR is an estimated 172 (my calculation) and it has two Supply Mains (see photo #1). Neither Supply Main has a Main Vent and I believe it needs one so I am wondering where it can be installed. For Supply Main 1, I believe it can be placed at the start of the Drip Connection (see photo #2). I don't have a photo for Supply Main 2, it does go to the garage though. I also plan on replacing the Wet Return with 1" copper type M starting from the Drip Connection. Its piping looks like 2" to 1-1/4" please note.

Thank you and have a safe/merry holiday and Happy New Year!

neilc

in #2, what is the pipe above the main?
the picture is a little dark, does that takeoff continue past the 45 at the floor joist?
and that's just a coupler before the lateral?
if a vent can't go up on the main, then,
yeah, repipe from the 90 on the main, to the floor,
drop down a short nipple, add a tee for a main vent riser, then continue to the floor and wet return

ranzerox

Hi @neilc, that 45 continues past the floor joist. It's looks dark but it's actually a ceiling wood panel stained dark. Regarding the coupler before the lateral, it's another 45 heading to the left. Thanks