Repairing a broken shower valve is a task you can complete yourself with simple, easy to find tools and materials. Often all that will need to be replaced in the shower valve cartridge are the O-rings and washers. Follow these tips to remove, repair and reinstall your shower cartridge valve.
Step 1 - Remove the Valve Cover and Find the Cartridge Serial Number
Turn off the water to the bathroom, or at the house supply if necessary. Slip an Allen wrench under the seam where the shower control handle meets the valve cover. The serial number for the valve will be on the black valve cover sleeve. You need this information to purchase the correct parts for your shower valve cartridge.
Step 2 - Lift the Cover Base
Pry gently with the Allen wrench under the cover base or escutcheon and lift it off. Check the escutcheon liner for rips or wrinkles. If the liner is damaged, buy a replacement.
Step 3 - Turn the Shower Diverter Up
Turn the shower diverter valve up and wait while the water retained in the shower arm and head drains out. Next, remove the valve cover sleeve and the shower valve cartridge.
Step 4 - Remove the Valve Cover Sleeve and Valve Stem
Use the Philips head screwdriver to release the four screws holding the valve cover sleeve and stem. Pull the valve cover sleeve out by its edge, not by the stem, and set the assembly aside on the sink ledge.
Step 5 - Pull Out the Shower Valve Cartridge
Grasp the shower cartridge and pull it out. The shower valve cartridge is a 2-chambered device made of plastic, which controls the hot and cold water flow and mixture to the shower head. Check the O-rings on one side and the 2 small washers on the other for splits, punctures and wrinkles.
Step 6 - Take the Shower Valve Cartridge Along to Purchase Parts
Go to a reputable plumbing supply center with the shower valve cartridge and buy the replacement O-rings and washers. Purchase an entire replacement cartridge while you are there, as you will usually have to replace the cartridge after 5 years.
Step 7 - Replace the O-rings and Washers on the Cartridge
Remove the old O-rings and washers, and put the new ones on the shower valve cartridge, seating them firmly in their slots.
Step 8 - Reassemble the Shower Valve
Reinsert the shower valve cartridge into its wall slot, with the large O-ring side facing inward. Put in the valve cover sleeve and stem and secure it to the wall again with the screws. Replace the escutcheon liner and put the escutcheon back over the valve cover sleeve and stem. Test the shower valve now for leaking, by turning on the water again, and twisting the valve cover stem lightly with your fingers. If you have no leaks, continue reassembling the shower control handle. If the shower head is still leaking, remove the old shower valve cartridge and replace it with the new valve cartridge you purchased.