| |
Project Difficulty:
Moderate
|
|
 |
|
|
|
|
|
The plumbing system in your home delivers potable (drinking) water and carries away waste and sewage. It accomplishes this through separate but interdependent subsystems: water delivery (hot and cold), drain/waste, and venting as shown in Figure 1.
Potable water is pumped from reservoirs by companies that comply with government regulations. If your water doesn't come from a municipal source, it comes from your own private well, in which case you're responsible for its quality. If you reside in an urban or suburban area, the plumbing system in your home is probably connected to a municipal sewer that carries the waste and sewage from your house out to a treatment plant. If you reside in a rural area, you probably have a septic tank buried in your yard to handle sewage (which contains animal or vegetable matter in suspension) and a distribution box to dispense waste (liquid). Periodically, a septic tank has to be emptied by trained service personnel who haul the matter to treatment facilities.
|
|
|
|
|
| |
|
1.
Water Delivery
Water enters the home from the municipal or private source through a water main and then passes through the water meter in your house. Then it flows through branch lines to plumbing fixtures such as sinks, toilets, bathtubs, and shower stalls, and to appliances such as washing machines, dishwashers, water heaters, and hot water or steam boilers. Branch lines also carry water to points outside the house, including faucets, in-ground sprinkler systems, and swimming pools. A cold-water line delivers water to the water heater, which in turn heats the water that is then distributed through hot-water lines.
In a modern home plumbing system every pipe transporting potable water should have a shutoff valve so that if it becomes necessary to turn off water in a particular pipe (for a repair or as a precaution), you won't have to shut down the entire system. The shutoff valve on the main pipe, when closed, stops the flow of water throughout the house; it is usually located on the inlet side of the water meter. Some homes also have a shutoff valve on the intake side of the water meter. Ideally, shutoff valves on each pipe should be near the fixture or appliance that the pipe serves. There should also be a shutoff valve on the interior side of any pipe where it penetrates the wall to the outside, for winter drainage of the outside pipe and valve.
If your home is served by a well, the pump (probably of the submersible type) and holding tank are parts of the water delivery setup. The pump delivers potable water into the holding tank, where it is held until needed.
|
|
2.
Drain/Waste and Venting
A network of various size pipes transports waste and sewage to the sewer or septic tank. (From a septic tank, other pipes transport the material to the distribution box and drainage fields.) The largest pipe is the soil pipe, into which all other pipes drain. Toilets utilize soil pipes that are as large as the main soil pipe into which they empty. The water in a toilet bowl serves two purposes: to carry away sewage and waste and to block sewage gas from permeating the house.
Each sink, bathtub, stall shower, bidet, washing machine, and dishwasher in a home is outfitted with the smallest diameter pipes of the drainage network. Called waste pipes, each has a curved section, or trap, that remains filled with water and blocks sewer gases. In a sink, the trap is usually in view right beneath the sink; with other fixtures and appliances, the trap is exposed below the floor in the basement. If the home doesn't have a basement, the trap may be embedded in the floor with access, typically, through an opening fitted with a removable cover.
Any soil pipe or waste pipe of a modern plumbing system should be outfitted with a removable cleanout plug that allows easy access into the pipe should it becomes clogged. A closet drain (the curved section of pipe beneath the base of a toilet) does not have a cleanout plug. Extensions from the soil pipe project through the roof of the house for venting. Each fixture and appliance are connected to an extension via a vent line. Venting is necessary to maintain an equalization of air and/or water pressure throughout the drainage network so that traps and toilet bowls won't have water pulled out of them. This siphoning action would leave the house exposed to sewage gases. One or more venting methods may be employed. They include continuous venting, dry venting, wet venting, individual venting (or reventing), loop venting, relief venting, and side venting. The positioning of vents is established by local plumbing codes.
|
|
|
|
