If you need to replace the entire shower valve and the parts that go with it, you may want to consider a valve rebuild kit. Shower valve kits cost between $20 and $250, depending on the type of valve.

If you haven’t flushed your water heater for a while, and sediment has built up, you may find that the tank takes a long time to drain. That’s another sign that it’s time to replace the valve.

That’s when the water is leaking from behind the handle, basically in the wall. Sometimes you can just unscrew the faucet mounting screws from the home’s wall and twist off the spigot.