A water control system including a showerhead and a tub faucet. The faucet has a valve configured to automatically restrict fluid flow through the faucet and direct fluid to the showerhead as a function of a parameter, such as a predetermined water temperature. The faucet has many modes of operation, including a Reset Mode, an Auto-Divert Mode, a Bypass Mode, and a Cold Mode. One embodiment includes an auto divert tub faucet that can be reset with less than 10 lbs. of force that is ADA compliant. Another embodiment includes a faucet configured to prevent hammering. Another embodiment includes a faucet configured to prevent leakage over time, and another embodiment includes a universal adapter allowing the faucet to be joined to the adapter without requiring hardware.