Plate IV. Water Closet Connections
Plate 4. Connections for Water Closet
The waste for the water closet should be 4 in. in size, but never less..
When cast-iron soil pipe is used, the connection is made by means of 4-in. lead pipe or a 4-in. lead bend, the pipe or bend being wiped to a brass ferrule which is caulked into the soil pipe, and the floor connection generally being made by means of floor flanges, the latter being considered under Plate 17. The connection of the water closet to wrought-iron soil pipe is shown under Plate 45.
The water closet should never discharge into a soil pipe of less than 4 in.
The lead bend is generally connected into a T-Y or modified form of this fitting. It is preferable to connect into a bend and Y-branch, as shown in Plate 40, Fig. D, or into the same combination of fittings arranged vertically. Such connection is often impossible, however, owing to lack of space, although in larger work, such as public toilet rooms, it may often be used without difficulty.
The water-closet flush tank should be set so that the bottom of the tank is as nearly 6 ft. from the floor as possible. This tank should be of seven gallons capacity, although on cheap work tanks of five gallons capacity are largely used.
The flush pipe from tank to closet should be 1 1/4 in. in size, but never smaller, as this size is required to deliver the required volume of water with the necessary rapidity.
The flush pipe may be connected rigidly to the water closet or by means of a slip joint or rubber elbow. The latter two connections are preferable, as any settling of floors or slight movement of the fixture does not result in breaking off the connection to the bowl, as often happens in the use of rigid connections.
The flush tank should always be provided with a flush valve of the siphon pattern. In the use of this valve, simply a slight pull on the chain is needed to flush the entire contents of the tank, while in the use of the ordinary flush valve the flushing of the water closet continues only so long as the chain is pulled down. The flush may be operated in many other ways than by a chain and pull - by the weight of the person using the fixture; by the opening or closing of the door; by means of a push button operating a crank or lever to which the chain is attached. The latter method allows the tank to be concealed behind walls or partitions. This method not only allows the unsightly high tank to be concealed, but also enables the working parts of the flush tank to be located in such a place that mischievous or ignorant people are unable to destroy or damage them in any way, an evil often encountered in public toilet rooms.