Turn off the water supply to the mix-it valve, and remove the shower handles and wall escutcheon.
Remove the stem retainer, as well as the nut and stem from the valve's body.
Clean out and remove the valve's body by inserting a ¾ inch wire fitting brush into the body and then rotating it clockwise.
Insert a deburring tool into the entrance of the valve's body and rotate it clockwise, making sure to exert pressure outwards. The sharp edge should be removed from the valve's body; this makes it easier to install the new valve.
Flush the metal shavings and other debris from the fix-it valve's body by turning one of the stops on. Also, figure out which side the hot and cold water supply is on.
Lubricate the rubber end of the new mix-it valve with heatproof grease, this will make it easier to install. If your cold water supply turns out to be on the right side of the valve's body, you'll need to install the new valve with the arrow pointing up. If your hot water supply happens to be on the right side, install the new valve with the arrow facing the down position. Then, using the channel locks, grasp the new valve and push it into the body using pressure.
Turn the stem retainer nut clockwise with the wrench while holding the fix-it valve in an upward position. The stem should not turn while it's being tightened. It's important that the stem retainer nut is tight because you do not want the mix-it valve to be turned once the process is complete.
Turn the water source back on to the valve's body and reinstall the wall, escutcheon plate, and handle.
Things You Will Need
- Phillips screwdriver
- Channel locks
- Mix-it valve installation kit
- ¾ inch wire fitting brush
- Deburring tool
- Heatproof grease
- Seat areas on older valve bodies may be eroded because they are deeper than normal, which causes the mix-it valve to leak.