This section is from the book "American Plumbing Practice", by The Engineering Record. Also available from Amazon: Plumbing: A working manual of American plumbing practice.
PLUMBING IN THE WALDORF HOTEL.
These pumps connect through pipes O O O with the 8-inch horizontal pipe D, from which two 5-inch pipes E E rise, connecting to the two attic tanks. They are cross-connected by the 5-inch pipe P at the level of the bottom of tank A. Pipes E E discharge into the tanks through the 5-inch back-pressure valves G G, set so that the disk of the valve may be held open by the lever and chain connection H extending to the engine-room, where the ends are secured in such manner that they may be released at the will of the engineer. The details of valve G are shown in this Figure. The tanks are built of fg-inch wrought iron, and each has a wrought-iron safe pan with a 2-inch waste a a. The tanks may be emptied through the 1½-inch emptying pipes b b, and c c are the 4-inch overflow pipes. All these pipes may empty into the rainwater leader pipes.
Upon each floor there is taken off from pipes E E a 2 ½ -inch connection to which is attached valve I for fire service. Each of these valves has connected 100 feet of linen rubber-lined hose and a hose pipe, all of which are housed upon a swinging rack ready for immediate use. For fire-extinguishing the 16,000 gallons of water in the attic tanks is always available, the water passing back to the rising lines E E through the back-pressure valves G G which are held open by the lines H H. By letting go either line H the flap of the valve which it controls is closed and by starting the 20"x 11" x 15" Worthington steam fire pump J, which is connected to the pipe D, its full pressure may be directed into the lines being used for fire purposes. At the ends of pipe D are located the 4-inch check valves K K. The discharge ends of these connect with 4-inch pipes passing through the walls and turning upward, where they end with standard fire-department coupling connections. In the event of a fire calling the city department to the building the firemen would couple their hose to this pipe, using the pipes E E as stand-pipes, and availing themselves of the hose already in position upon the several floors. Safety valve Q on pipe D is intended to relieve excessive pressure in the event of the closing of valves G G while the steam pumps are working.
The height of the water in the attic tanks is recorded in the engine-room by means of a pneumatic mercury gauge especially designed for this work by Mr. Hanson, the foreman plumber engaged upon it. It is illustrated in Fig. 7. In each of the tanks an air compressor is erected, formed of the 3-inch wrought-iron pipe A, which is of equal height with the tank. The base, a cast-iron flange, is fastened to the tank bottom, and close to it is the open centered tie B. The upper end of the compressor is reduced to three-eighths of an inch in diameter and is connected to the ¾-inch pipe C, which, descending to the engine-room, is there connected with the mercury column H, Fig. 7. It is controlled at the point of connection by the valve D. The mercury column is of ordinary construction, except that at the base of the reservoir E is inserted the close-fitting piston head F, which may be raised as required by the screwed stem G to allow of adjustment when, by reason of reduction of the quantity of mercury in the column, the scale fails to accurately register the height of water in the tank. The tank being empty mercury is introduced into the reservoir and columns until it shows at O. The valve D is opened and the water as the tank is filled closes the opening B, preventing the farther escape of air. As the water rises it gradually compresses the air, which pressure, transmitted through the pipe C to the mercury in the reservoir E, drives it up in the graduated glass tube H, which is long enough to indicate a full tank. The full marks on the glass agree with even feet of water in the tank, and the one-twelfth graduations correspond to immediate inches of depth. As the water is lowered in the tank and the air pressure is lessened, the mercury drops in the gauge glass.
From each of the attic tanks the 4-inch wrought-iron pipes L L, Fig 6, which, descending to the cellar, are connected through 3-inch pipe R with the 3ox84-inch heavy wrought-iron tank M. On the top of this tank is connected the 4-inch horizontal drum N, from which radiate the 2-inch cold-water pipes P P, etc. leading to the several riser lines supplying cold water to the plumbing fixtures on all the floors above the first. All connections to tank M and the pipes from drum N have valves for use in case of repairs. These risers are cross-connected by a 4-inch horizontal pipe so valved that either tank may be cut out of service if necessary. Pipe R also serves to connect the cold-water pipes L L with the wrought-iron boiler S in the basement. This is built of ¾inch iron, and is strongly made to withstand the pressure from the attic tanks. The water in this boiler is heated by a brass coil, to which steam from the power boilers is admitted. There are also arrangements for heating this coil by exhaust steam from any of the several steam pumps or engines in the cellar. On the top of this boiler is built the double-connected 4-inch drum T, from which is laid the 2-inch galvanized-iron pipes U U, etc. supplying hot water to plumbing fixtures above the first floor. Pipes T rise to a point above the highest fixtures and then return by the 1½-inch galvanized-iron circulation pipes V to the 3-inch drum W, which is double-connected to the bottom of the boiler S, thus forming a circulation loop which gives hot water at any point of draft on its line. The tops of all these loops are relieved of air or steam, which would interfere with the circulation, through the ¾ inch galvanized-iron relief pipes X.
Upon the same floor as tank A is the 3ox84-inch wrought-iron tank Y, Fig. 6, which is used for heating the water for the laundry located on the floor immediately beneath. Cold water enters the boiler from the pipe F through the 2½-inch pipe e having the check valve Z to prevent the return of hot water into the tank A. The water in boiler Y is heated by a brass coil to which steam is supplied from a live-steam pipe in the laundry service, or by the exhaust steam from the 40 horse-power engine in the laundry which furnishes power for all the laundry machinery. From the top of this boiler Y is laid the 2½-inch galvanized-iron pipe d to the laundry, and from the highest point of this pipe is carried a ¾-inch relief pipe/ into tank A.