Hi everyone. I know this has been discussed but I am unclear. I have to install a Liberty 404 for a utility sink and washer. I can go into the sewer line on the first floor but not the vent line. My question is can I just run a 2 inch pvc pipe 3 feet high with 2 90s to clear a goose neck. Other than a potential smell from the gray water will this set up work. Btw I’m arguing with a plumber that an AAV won’t work. He keeps saying yes.