Why identification comes first
Shower cartridges and stems look alike but aren't interchangeable. A part that is a few millimeters off, or has a different spline, won't seal or won't hold the handle. Getting the identification right before anyone buys a part avoids repeat visits and returns.
Many Fullerton bathrooms still have valves from decades ago, and their markings may be worn or hidden under the trim. Record what you can see from the outside; a plumber can do the rest once the trim is off.
From outside the wall
- Number of handles: one, two or three
- Handle motion: lift, pull, push-pull, rotate, or separate temperature and volume
- Any logo or name on the handle, cap or trim plate
- Shape of the trim plate: round, oval, square
- Where the diverter is: on the spout, a middle handle or a separate knob
- Rough age of the bathroom or last remodel
Record your valve
| Detail | What you found |
|---|---|
| Handles | |
| Brand marking | |
| Handle motion | |
| Diverter location | |
| Trim plate size and shape | |
| Stops visible behind trim? | |
| Photos taken (handle, trim, spout, cartridge) |
Photos that help most
- Straight on.The whole trim and handle, square to the wall, with the spout or head in frame if possible.
- Close-up of markings.Any logo on the handle cap, lever or trim plate.
- Side view.How far the handle and trim stick out from the tile, which hints at the valve depth.
- With trim removed.Only if water is off and you are comfortable: the cartridge end, its retaining clip or nut, and any stops.
Terms on the parts label
- Cartridge
- A one-piece insert that controls flow and mixing in many single-handle valves.
- Stem
- The threaded part in each handle of a two- or three-handle valve.
- Seat
- The surface a stem washer presses against to stop water.
- Splines
- The ridges on a stem or cartridge end that grip the handle.
- Escutcheon
- The decorative plate that covers the opening around the valve.
Common questions
What if there is no brand anywhere?
That is common on older valves. A plumber can usually identify it from the cartridge or stem once the trim is off.
Can I take the trim off myself?
Usually it is a set screw or cap and a few screws. Turn off the water first if you will go further than the trim.
What if no matching part exists?
Then the valve body is usually replaced. See the valve replacement guide for what that involves.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.