In Fig. 294 is illustrated a complete pressure hot- and coldwater supply system for a residence, with circulation, there being three separate lines of the latter. By many workmen the subject of circulation is not well understood, but a clear understanding of the subject is necessary, if satisfactory supply work is to be constructed. The subject of circulation must be considered at every point on the hot-water supply system, and as conditions are of such great variety, it will be readily understood that to be successful, the workman should be familiar enough with the subject to apply its principles under any and all conditions. As previously stated, not only is this knowledge necessary, but practical experience in the installation of such work is of very great value. From the preceding consideration of the subject, it should now be clear that the use of the circulating system of hotwater supply is of very great advantage, and this is especially true of large work. It will be found that on large work, and on smaller systems as well, the saving in water bills will not be long in covering the additional first cost of installing circulation, and it goes without saying that such a system is far more convenient than the ordinary system of hot-water supply. CHAPTER XXV PROBLEMS IN RANGE BOILER WORK WHILE the great majority of range-boiler connections are simple and straightforward, there are numerous instances, constantly arising in the experience of the plumber, which call for much ingenuity on his part, as well as a practical and theoretical knowledge of the subject of circulation. These complex conditions in range boiler work, arise from the varied locations of range and boiler, relative to each other; from the unique requirements that the supply system must fulfill; from the use of more than one boiler; from the use of more than one source of heat; from the requirement that heat by radiation must be obtained from the hot-water supply system, and from numerous other causes. The successful solution of these complex connections that are continually being met by the plumber, present a field of work in which he can display his ignorance of anything out of the ordinary line of work, or in which, if able, he may display a knowledge of the principles of circulation which will gain for him the respect and confidence of his customers. In this chapter some of the problems in range connections, which are continually requiring solution, will be taken up. It should be stated, however, that the problems considered are really few in number as compared to the great variety of such problems which might be considered if space could be devoted to the subject. Those which are considered, however, are of importance, and a thorough understanding of them will go far in helping to solve other problems in circulation. One of the more simple, but yet important connections, is that shown in Fig. 295, the use of which is to produce a quick supply of hot water. By means of the ordinary connection of the flow pipe, which enters the side of the boiler, hot water is stored in the boiler and from there delivered to the fixtures. When the fire is first built in the range, however, considerable time must elapse before the hot water delivered to the boiler can store itself in sufficient quantity to be of any service. Before hot water can be delivered to the fixtures from the boiler, the hot water entering the latter must heat up a large body of cold water standing in it. By means of the connection shown in Fig. 295, however, hot water can be delivered directly into the flow pipe from the boiler in a very short time after the range fire has been Hot Water FIG. 295.-Quick-Heating Range Connection. started. Not only is this advantage gained, but hot water will store itself in the boiler almost as readily when this connection is in use as when the side connection is made. As the water in the flow pipe cools slightly, it must inevitably fall back into the boiler to make room for the hotter water that is being constantly delivered to the flow pipe. It is in this way that storage of hot water goes on. Under many conditions this form of connection is of special advantage. For instance, in many homes, the kitchen range fire is allowed to go out each night, and when it is rekindled the following morning, hot water will be required as quickly as possible to provide it at the kichen sink. It can be readily seen that in this case the quick heating connection will give far more satisfactory service than the side connection into the boiler. Fig. 296 will show that this same connection can be provided Hot Water to Fixtures FIG. 296. Quick-Heating Range Connection for Horizontal Boiler. for the horizontal boiler equally as well as for the vertical boiler. A modification of the quick heating connection is often used, as shown by the dotted lines in Fig. 295. This form of connection consists in running the flow pipe from the range, up and into the flow pipe from the boiler, and taking a branch from this line into the side of the boiler. This plan can be used to advantage, as it gives a quick supply of hot water, and storage is made through each connection. Another means of obtaining a quick supply of hot water is by the use of a gas heater, as shown in Fig. 297. Gas heaters are made in a great variety of styles, and by many |