Fig. 76 shows the supplies of the same job, on the kitchen ceiling. The system provides positive circulation to keep hot water near the bathroom fixtures. The hot supply is on the left side for each fixture. There is only one pipe crossed, and it does not interfere with draining the job. There are no traps in the supplies, nor drain cocks, to be forgotten. There is a relief line from the reservoir to the tank, so that it is not possible to close every means of escape for vapor or steam from the reservoir. The hot supply and cold service are both open to the air at the tank.
The disadvantage of this job is that the cocks which stop the hot water to the bathroom are over the reservoir. While each fixture is controlled separately, by cocks in addition to its regular faucets, all the lines are not under control individually. This arrangement embraces every feature essential to good service and with the least possible material. The nickeled supply in bathroom is thus reduced to a minimum, and the chances for leakage to do damage are greatly lessened. For comparison, the kitchen work of an actual installation with separate supplies, having one bathroom and three odd fixtures, is shown in Fig. 77. This number of fixtures is considered about the limit in strictly separate supply work for residences, when all the lines radiate from one point, as they do in this case. In order that their purpose may be understood, the pipes shown in Fig. 77 are numbered. Pipe 1 carries the water from the house force-pump to the tank, and is arranged to discharge over the top of the tank. The tell-tale pipe, 2, is from the tank, and discharges in the sink, so that the person using the pump will know, when water flows from it, that the tank is full to overflowing. The cold-water supply to the butler's sink is No. 3. No. 4 is the hot-water supply to the same fixture. Pipe 5 is the return circulation from the bathroom hot supply. To make proper circulation certain at all times, regardless of the trap in the hot-service pipe made by dropping from the boiler and running across under the sink before rising to the second floor, the hot-service pipe is continued to the attic and a return made from there, an air pipe being taken from the highest point over the tank, to prevent its becoming air-bound. The position of the stop-cocks is such that they will drain without giving special attention to the waste water, which discharges into the sink; and the cocks are within easy reach from the floor. Pipe 6 is the cold-water supply to the bathroom fixtures.
The supply to the water-closet tank is taken from pipe 9, which passes under the closet room,'a cock being placed just above the floor. Pipe 7 is the hot-water supply to the bathroom fixtures. The main cold supply from the tank is pipe 8, which has a cock over the sink, and is also provided with a valve at the tank. Pipe 9 supplies cold water to the laundry, the hall lavatory, and the water-closet already mentioned. Pipe 10 supplies hot water to the laundry and the hall lavatory.
All of the service pipes, both hot and cold, above the first floor, are continued upward from the kitchen ceiling through a partition to and over the tank. This allows air to enter the pipes and drain the lines when the stop-cocks on them are turned off.
Baths do not need circulation for the same reason that lavatories do. Lavatory faucets are small in nozzle, as a rule; only small quantities of water are needed at a time; and it is annoying to have to waste time in drawing out cold, "dead" water and enough more to warm the pipe line, before warm water can be had at the faucet. Where the water must be pumped by hand this is still more aggra vating. Kitchen sinks are close to the hot supply source, and do not need circulation. Lavatories and other fixtures remote from the bath or main toilet room, are sometimes served from the circu lating loop instead of separately.