I have a plumbing drain venting question. I installed a steam shower which is a little unique, as it is a stand-alone item that is assembled after the bathroom is completed. All they called for was a 1-1/2" drain be located at floor level off to the side of where the shower will be located. I called in a plumber to do this part, as we had to jackhammer concrete and attach this to the underground line. This was done, bathroom was completed, and shower was built. After I hooked up all the water lines, the drain line, I discovered I was having issues because it wasn't draining properly. I realized that the plumber who Installed the main drain didn't tie in a vent line, or the original home builder didnt build one into the original plan. So, to try and fix this I tee'd off the drain line before the elbow heading underground , brought it up about 4 feet, with about 3 abs elbows, and installed an air admittance valve at the top of the vent line I made. After I did this it still didn't drain properly. I removed the valve completely, and now I have a 1-1/2 pipe with the end exposed. But it works perfectly now without the aav. I'm assuming that there was not enough vacuum pressure to open the aav. My question is can I just leave it open like it is, or is there some other device I should put on the open pipe end? It has been exposed for about 2 weeks and there has been no smell at all, but the toilet has not been installed yet. Not sure what to do besides calling a plumber in, or finding someway to vent directly outside the wall but that will be difficult. I have attached a very rough sketch to show basically what was done. I would appreciate any and all thoughts on my next step.
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