Most people don’t pay attention to their home’s plumbing until a sink or toilet clogs or a pipe breaks. That’s too bad, because plumbing really is an awesome system in which pipes, valves and fixtures supply fresh water and take away wastewater.
In fact, a home’s plumbing system works a lot like a human’s circulatory system. Understanding that basic idea helps homeowners figure out when they can fix a plumbing problem themselves or when it’s time to call in a professional.
A plumbing system is made up of two distinct subsystems: supply and drainage. These subsystems must be kept separate from one another or unhealthy contamination results. The potential threat to people’s health from faulty plumbing is one of the reasons that all 50 states require plumbers to be examined and licensed.
What’s more, plumbing is a construction technique that’s governed by the basic laws of physics. In other words, the water that flows through a home’s plumbing system can be affected by pressure and gravity, like the timeless saying of “water seeking its own level.” By recognizing this, homeowners can get a better knowledge about which repairs they can make on their own, and which repairs need the skills of a qualified plumber.
In the supply system, fresh water (sometimes called “potable water”) comes into a building under pressure. This pressure pushes the water to wherever it’s needed. As a public utility, the supply of fresh water is regulated by local and regional governments, which charge users for the construction and maintenance of the water system. That’s why there’s a meter attached to the plumbing that comes from the street into a home, factory office or store. The meter registers how much water that building is used, and that reading is noted to compute the user’s water bill.
Somewhere near the meter is the main shutoff valve, also known as a stop, that halts the flow of water in an emergency, or when the water service is discontinued. This is the valve that is turned when a major plumbing emergency occurs which requires that all water be cut off. This cutoff is crucial because a broken pipe can flood a building in a short period of time. Fortunately, smaller plumbing repairs don’t require shutting down the entire water flow. That’s why sinks, tubs, toilets, and other fixtures have individual shutoff valves.
The water that comes in to a building isn’t heated; hot water requires the use of a water heater. One pipe from the main supply carries cold water into the heater, and then another pipe carries the heated water throughout the house as needed. A thermostat on the heater lets a plumber or homeowner set the water temperature. Most home systems are set somewhere between 140 and 160 degrees. However, water heated to 120 degrees is sufficient for most needs, as well as being more economical and more environmentally friendly, since it uses less power to heat the water.
While supply and drainage systems don’t overlap in their operations, they do need bridges between them. Otherwise, how would the fresh water supply that’s been used for cooking and cleaning be transferred to the drainage system? Plumbers know these “bridges” as fixtures, such as toilets, tubs, sinks, washing machines, dishwashers and so on. Any device that draws in fresh water and drains away wastewater is a fixture. They’re the key mechanical devices that keep the supply and drainage subsystems separate from each other.
So now you’ve used the water and it goes down the drain. What happens next? Remember we said earlier that plumbing relies on pressure and gravity to work? Drainage is where gravity takes over from pressure.
Vents bring air into the drainage system to encourage the flow of water and waste matter. Drainage pipes are equipped with traps, typically an S-shaped curve in the pipes that aids the force of the drainage and keeps sewer gas from backing up. Wastewater and any matter it carries drains from buildings because all drainage pipes angle downward so that gravity pulls the water down. This pipe, known as a sewer line, keeps pitching downward until the wastewater reaches a septic tank or a sewage treatment plant. The entire drainage system in a building often is known as a DWV or drain-waste-vent system, because all three components must be present for the system to work properly.
Know that you know how plumbing systems work, what’s the first thing to do if you have a problem with your supply or drainage? If you answered “turn off the water,” go to the head of the plumbing class!
When the plumbing problem needs more than a simple fix, call a licensed Memphis plumber for prompt, professional service.