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.
The flapper is a flexible rubber or silicone flap that covers the flush valve opening at the bottom of the tank. Pressing the handle lifts the flapper by a chain, the tank water rushes down into the bowl to flush it, and once the tank empties the flapper falls back over the opening to let the tank refill and seal. It is the single most common cause of a running toilet, and one of the easiest plumbing parts a homeowner ever replaces.
Over a few years the rubber hardens, warps, or grows a film of mineral and chemical residue, and it stops sealing flush against the seat. Water then leaks past it from tank to bowl, the level drops, and the fill valve kicks on to top it off, the cause of a toilet that randomly runs for a few seconds or hisses all night. A quick test is a few drops of food coloring in the tank: color seeping into the bowl without a flush means the flapper is leaking.
Flappers are cheap and snap onto the flush valve in minutes, but they must match the toilet, since flush valves come in different sizes. A chain set too long or too short causes its own trouble, hanging the flapper open or holding it shut, so adjusting the chain is part of a clean replacement.
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- 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.
- Aerator : An aerator is the small screened tip that screws onto a faucet spout, mixing air into the stream to soften the flow, cut splashing, and save water.
- Sillcock / Hose Bib : A sillcock, or hose bib, is the outdoor faucet on the side of a house where a garden hose connects, with frost-proof versions designed to resist freezing.
- Pressure-Balancing / Mixing Valve : A mixing valve blends hot and cold water to a set temperature, and the pressure-balancing version protects a shower from scalding when water is drawn elsewhere in the house.