Step 4 · Install the Sanitary Tee
This is the most critical step. First, dry-fit the sanitary tee into the gap you created to ensure a proper fit. The side opening (branch) of the tee must point straight up. Once you confirm the fit, you can begin the solvent welding process. Open the PVC primer and cement. Using the dauber attached to the lid, apply a liberal coat of the purple PVC primer to the outside of the pipe ends and the inside of the tee's sockets. The primer cleans and softens the plastic. Immediately follow up with a coat of PVC cement to the same surfaces. Firmly push the tee onto one pipe end, give it a quarter turn to spread the cement, and hold it for 30 seconds. Repeat for the other side, ensuring the tee remains oriented correctly.