The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
How To Design And Install Plumbing
The construction of a water closet trap appears to be the same as that of an ordinary trap, with the inlet and outlet passageways of same diameter. This, however, is not the case. The diameter of the outlet passageway is smaller than that of the inlet passageway. It is built with short offsets and turns so that the flow of water through it is retarded, thus causing a head of water to be built up in the fixture. When the closet is flushed, the water passing through the outlet passageway eliminates the air it contains, thus producing a partial vacuum. Atmospheric pressure and the head of water retained on the inlet side of the trap force the collected organic solids from the fixture. Fig. 280 illustrates how this siphonic action occurs in a siphon washdown closet bowl.
Siphon Jet Washdown Closet. It is the objective of all water closet designers to produce siphonic action as rapidly as possible. For this reason some closets are constructed with an integral jet connected to the dip of the trap. This type of fixture is called the siphon jet closet. Its action is identical with that of a washdown closet, but it provides faster elimination of waste, because a stream of water is delivered immediately from the closet spud to the outlet passageway of the fixture, making it unnecessary to have a head of water in the bowl.
Both types of closets are standard. Fig. 281 illustrates how the action of the jet induces flushing activity in the siphon jet closet bowl.
UNSANITARY CLOSETS
Washout Closet. The washout closet, Fig. 282, is obsolete and its installation is no longer permitted. It is very unsanitary because of having too much fouling surface. The closet from outside appearances is similar to the washdown bowl. The interior construction of the bowl, however, is different. In this type of fixture the organic materials are deposited into a shallow water well. The well does not have sufficient depth to float these wastes, and the sides of the bowl are not washed down with each fixture flush. Fouling of the fixture results.
