The Basic Water Supply System

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The labyrinth of pipes, fittings, valves, and fixtures that constitutes the plumbing system in your house can be a complex puzzle. However, like most devices and systems designed by human beings, it's only bewildering to those who are unfamiliar with it. If you are interested enough in the subject to read this guide and look at the drawings, you will soon see that plumbing is just a series of rather simple and logical connections of pipe, fittings, and fixtures. You may find that making repairs or even adding on to the system is quite possible for you to do all by yourself.

ill.9 How to Check for Leaks: Just put the probe on a pipe and listen at the ear piece for the hiss or gurgle of a leak.

Supply Lines and Branches

It all starts with your main supply line. If you get your water from a public water works, it will probably come from the water main under the street out front, through your water meter and your main shutoff valve. In areas where the ground freezes deeply in the winter, the meter will be in the basement or crawl space. In warmer areas, ii will be in a little concrete well near the curb. If you have a private water supply system, the main supply line will start at your storage tank or pump.

In any case, the supply line that enters your house should be at least 3” pipe. One-inch pipe is even better if you are planning any additions or replacements. Obviously, the larger the pipe, the more water it can supply. But even more important, a larger pipe will cause less friction. When the water pressure is low, like during TV commercials when everyone uses their bath rooms at the same time, both the volume and friction factors are important to maintain a steady, even flow of water.

Alter the main line enters your house, it usually runs near the water heater. There it splits in two, The hot-water pipe goes through the water heater and then runs parallel to the cold-water pipe to the laundry, kitchen, and bathrooms throughout the house At one or more convenient places in the basement or crawl space, the cold- water pipe branches to provide water to the outside faucets around the house and in the garden.

If the water entering the house must be treated in some way, the treatment units will be attached near where the water enters the house. Chemical injectors or filters will be on the main line in the basement or crawl space. Because softened water usually doesn’t taste as good as hard water and because the added sodium isn't considered healthy, water softeners are oft en placed on the branch line that goes to the water heater. This way only the hot water, used for washing and bathing, is softened. In some cases, although it makes the piping a little more intricate, unsoftened water is piped to the kitchen sink and maybe a wet bar or faucet used primarily for drinking, while softened hot and cold-water is piped to the laundry and bathrooms.

To make the plumbing system more economical to install and to keep pipeline friction to a minimum, architects and house designers try to locate bathrooms, kitchens, and laundries as close together as possible on the same floors and . when they are on different floors, directly above and below one another. As you can see in the drawing, this makes for a much simpler installation and one that uses much less pipe and fewer fittings.

Alter the main supply line enters your house, it divides into ¾-inch hot- and cold-water pipes, The branches that feed individual fixtures may be of ½-inch pipe. These water systems may be made of galvanized iron, copper, or plastic, depending on local codes and practices and the age of the house. Building codes are very specific as to what kinds of pipe and fittings are required or al lowed. Before you make any changes or additions, especially if you plan on changing from the kind of pipe already in your house, be sure to check with your building inspector

In cold climates where pipes can freeze—and some times in warmer areas, too—the entire supply system is sloped to low points where drain cocks will allow the drainage of all the pipes in the system. If your system is set up this way and you are adding to it, be sure to slope your new pipes slightly toward the drain cock.

Each fixture and appliance, without exception, should have its own shutoff valves Water softeners, filters, and other treatment devices, water heaters, dishwashers, washing machines, as well as all the sinks, tubs, and toilets should have a valve on both the hot- and cold-water pipes. If you plan on doing some or all of your own plumbing repairs and maybe some additions, installing any missing shutoff valves would be a good place to start and give you helpful practice.

Another constituent of a properly installed plumbing system is the air chamber or cushion. Air or inert gas trapped in a chamber compresses and cushions the shock when a nearby faucet or valve is turned off suddenly Because water isn't compressible it makes a loud bang and can damage pipes when it's stopped suddenly without this kind of cushion.

An air chamber is a vertical section of pipe on a supply line with a cap on top. It is usually hidden beneath cabinets or within the wall. The air in a pipe air chamber eventually dissolves in the water or leaks out around the cap, making it useless as a cushion. The cap must then be removed and a new supply of air allowed to enter.

If the cushion must be put within the wall or in another location where it isn't easily serviced, consider installing a manufactured shock absorber. These are made with inert gas and a bellows so they remain permanently effective without servicing.

ill.10 You will probably find the main shutoff valve near your property line.

ill.11 Water Supply and Drain Systems: machine drain; Supply stops; drains; Main stack vent; Secondary stack vent; Re-vent; Water- heater; Cleanout; Unsoftened water supply Cold, softened water; Hot, softened water; Vent system; Drain system; sewer

The Hot-Water System

A home hot-water system consists of a heater and a piping system that parallels the cold-water pipes to the faucets where hot water is desired. The heater is fueled by gas, oil, electricity, or the sun, depending on the fuel that's available in the area and the preference of the home owner. Most heaters can't heat water as fast as it can flow from a shower head or faucet, so they have a tank in which to store a quantity of hot water.

Home water heaters are generally available with tanks of 30- to 82-gallon capacity. The once-common 20-gallon tanks have become so unpopular that most manufacturers don’t make them any more. Gas and oil-fired heaters are usually 30 to 60 gallons. Electric heaters, be cause they heat water more slowly and have a longer recovery time, have tanks that can hold up to 82 gallons. Some manufacturers make a rapid-recovery electric water heater in which the upper heating element operates independently to heat the top quarter of the tank quickly. When the top quarter is hot enough, the upper element goes off, and the lower one comes on to heat the rest of the water slowly.

The size of your water heater tank depends on how much hot water your family needs at the time of peak usage—for example, in the morning or evening when everyone takes a bath or shower. Usually the number of bedrooms in a house is used to determine the size of the water heater. For a one- or two-bedroom house, a 30- gallon tank is recommended; for three bedrooms, a 40- gallon tank, and so on. If you have several children, you may want to have a larger tank than recommended.

In some areas of the United States demand water heaters are available. Also called tankless or instantaneous water heaters, they are common in Japan and Europe but haven’t been used in this country to any great extent since the copper shortage during World War II. These heaters have an intricate grid of copper ducts very much like an automobile radiator. When the hot water is turned on and flows through the heater, a large gas flame envelops the grid and heats the water to the de sired temperature as you use it. Because this kind of heater heats water only as you use it and does not have to go on periodically to keep a whole tank of water hot, it uses up to 20 percent less fuel than a conventional tank heater, You can probably find out about availability in your area through a wholesale plumbing supply or solar equipment dealer.

ill.12 Types of Water Heaters: Gas tank-type

Tank-type water heaters are basically simple devices. They consist of a thermostatically controlled burner or heating element that heats the water and an insulated tank to hold it until someone wants to use it. Because hot water is corrosive to metals, most quality heater tanks are glass-lined to help prevent them from rusting through.

Gas-fueled heaters have a burner very similar to the one on a gas kitchen range. A pilot light lights the burner when the thermostat indicates the tank water is cooler than desired. Hot exhaust gases from the burner go through the flue in the center of the tank, where they continue to heat the water as they pass by.

Oil-fueled heaters are less common but still in use where oil-fired furnaces are used. The water tank is suspended in the middle of the heater, and a small version of an oil-furnace blower heats the bottom and sides with hot gases before they are vented out the flue.

Electric water heaters have one or two heating elements that project through the wall of the tank into the water. Because there is no combustion, no flue is needed and no toxic gases or hot gases are emitted. An electric heater, therefore, can be placed in a closet or bathroom, where the building code would not allow a gas or oil- fueled heater. All water heaters do need a drain in case of overflow and for regular maintenance draining.

All water heater storage tanks should have a tem perature/pressure relief valve. This valve will relieve the pressure and thereby prevent an explosion if the thermostat malfunctions and the temperature or pressure within the tank exceeds predetermined limits. A properly installed relief valve will have an overflow pipe attached to it that directs any escaping water or steam outside or to a floor drain.

Google for information on passive, active, and auxiliary solar water heating systems, and what might be the best system for you.

ill.13 Electric tank-type; Pilot light; Cold-water inlet: Gas-demand type: Tankless or instantaneous water heaters use up to 20% less fuel than conventional heaters. Cold-water inlet with valve; Pressure relief valve; pipe; Anode; Electric cable, Thermostat, Insulated access door, Insulation, Copper heating coils, Burner, Drain valve, Gas supply with valve, Thermostat.


Friday, December 9, 2011 9:35 PST