Faucet Cartridge
A faucet cartridge is the replaceable inner valve that controls water flow and temperature in a modern single- or double-handle faucet, and the usual cause of a drip.
A faucet cartridge is a cylindrical insert that sits inside the faucet body and does the actual work of opening, closing, and mixing the water. Turning the handle rotates or slides the cartridge so its ports line up to let hot, cold, or a blend through. It replaced the old rubber-washer compression design in most faucets and shower valves, and because it is a self-contained part, a worn one can be pulled and swapped rather than rebuilding the whole faucet.
Homeowners meet the cartridge when a faucet drips, will not shut off fully, gets hard to turn, or runs only hot or only cold. The internal seals and O-rings wear or pick up mineral scale, and the cure is almost always a fresh cartridge of the exact type the faucet maker used. That matching is the catch: cartridges are brand- and model-specific, so identifying the faucet before buying the part saves a return trip.
In a shower the same idea applies, where the cartridge often doubles as the pressure-balancing element that protects against scalding. Pulling a stuck cartridge can fight back after years of scale, sometimes needing a puller tool, which is part of why a shower cartridge job costs more than a sink one.
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- Wax Ring : A wax ring is the soft sealing gasket that sits between a toilet base and the floor flange, blocking water and sewer gas from escaping at the connection.
- Toilet Flange / Closet Flange : A toilet flange, or closet flange, is the ring that anchors a toilet to the floor and connects it to the drain pipe below, holding the bolts that clamp the bowl down.
- Fill Valve (Ballcock) : A fill valve, the modern replacement for the old ballcock, is the tank part that refills a toilet after a flush and shuts off when the water reaches the set level.
- Flapper : A flapper is the hinged rubber seal at the bottom of a toilet tank that lifts to release water into the bowl on a flush, then drops back to hold the tank full.