How to Replace a Clogged Shower Valve

In this video, This Old House plumbing and heating expert Richard Trethewey replaces a clogged shower valve that would not allow hot water into the shower.

Steps for replacing a clogged shower valve:

1. Cover the tub drain with a rag to prevent any dropped parts from falling into the drain.

2. Unscrew and remove the handle and escutcheon plate from the shower valve.

3. Close the hot- and cold-water shutoff valves to the shower.

4. Use a pocketknife to carefully pry the retainer clip from the shower valve.

5. Hold a plastic shield beneath the valve to catch any water, then use pliers to pull out the old shower cartridge.

6. Smear waterproof grease onto the O-rings of a new shower-valve cartridge.

7. Push the new cartridge into the shower valve, making sure you correctly orient the hot- and cold-water indicators.

8. Press the retainer clip onto the valve to secure the cartridge.

9. Open the hot- and cold-water shutoff valves.

10. Reinstall the escutcheon plate and handle.

Tools: