Step 7 · Install Faucet and Test for Leaks
Before you can test the drain, you need to install the faucet and water supply. Install the new tub/shower valve body, securing it to the wall framing according to the manufacturer's specific depth instructions. Connect the hot and cold water supply lines to the valve, using Teflon tape or pipe dope on threaded connections. Install the tub spout, ensuring a watertight seal against the tub wall. Now, turn the main water supply back on slowly. Open the hot and cold faucets to bleed any air out of the system. With the water running, use a flashlight to carefully inspect all the supply line connections at the valve for any drips. Next, test the drain. Close the tub drain with its stopper and fill the tub with several inches of water. Inspect the connection between the drain shoe and the tub from your access panel or below. There should be no leaks. Finally, open the drain and let all the water rush out. As it drains, thoroughly inspect the P-trap and all the waste line connections you made. If any leak is found, shut off the water immediately, drain the system, and remake the leaking connection.