A plunger is a common device used to release stoppages in
plumbing. The tool consists of a rubber cup with an attached stick "shaft", usually made of wood or bronze. The cup is pushed down against the drain, and either pressed hard into the drain to force air in, or is pushed down until the rubber cup is flattened, then pulled out, causing a vacuum. The intent is to loosen or break up a clog, excessive material, or other blockage in a sink, toilet, bathtub, shower, etc.
A plunger is much more effective when there is water in the pipe because water does not compress easily and will thus transmit more of the applied
When a plunger is ineffective, it is often supplemented by a chemical
drain opener. If necessary, a plumbermay need to be called.
There are two basic types of plungers: toilet and sink. A sink plunger, pictured at right, has a flat rim designed to fit over a
sink, bathtub, shower, or similar opening to form a seal. A toilet plunger, pictured at the left in the image above, has a flange designed to fit into the bottom of a flush toiletbowl, with the flange entering into the exit pipe, forming a seal. The flange of a toilet plunger can be flipped up inside the plunger in order to use it as a sink plunger. If one is going to have only one plunger on hand, a toilet plunger is more versatile.
A third type of plunger is called a "Taze Plunger." The taze plunger is specifically sized to barely fit inside a pipe, and to use pressure to force a blockage through. The side of the taze plunger should scrape against the side of the pipe. The taze plunger is attached to a several-foot-long solid steel bar, and is inserted down a length of pipe to clear a running trap. The bar must be steel, or the pressure generated by its use would break or deform it.
* [http://www.thisoldhouse.com/toh/knowhow/plumbing/article/0,16417,193799-4,00.html#/ How to unclog a drain]
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